iOS 开发经验 - 转载

1、禁止手机睡眠 [UIApplication sharedApplication].idleTimerDisabled = YES;2、隐藏某行cell - (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath{// 如果是你需要隐藏的那一行,返回高度为0 if(indexPath.row == YouWantToHideRow) return 0; return 44;}// 然后再你需要隐藏cell的时候调用[self.tableView beginUpdates];[self.tableView endUpdates]; 3、禁用button高亮button.adjustsImageWhenHighlighted = NO;或者在创建的时候 UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom]; 4、tableview遇到这种报错failed to obtain a cell from its dataSource

是因为你的cell被调用的早了。先循环使用了cell,后又创建cell。顺序错了
可能原因:1、xib的cell没有注册 2、内存中已经有这个cell的缓存了(也就是说通过你的cellId找到的cell并不是你想要的类型),这时候需要改下cell的标识

5、cocoa pods报这个错误:unable to access 'https://github.com/facebook/pop.git/': Operation timed out after 0 milliseconds with 0 out of 0 bytes received

解决办法:原因可能是网络问题,网络请求超时了,只需要重试就行了

6、cocoa pods 出现ERROR: While executing gem ... (Errno::EPERM)

解决办法:
https://segmentfault.com/q/1010000002926243

7、动画切换window的根控制器 // options是动画选项[UIView transitionWithView:[UIApplication sharedApplication].keyWindow duration:0.5f options:UIViewAnimationOptionTransitionCrossDissolve animations:^{ BOOL oldState = [UIView areAnimationsEnabled]; [UIView setAnimationsEnabled:NO]; [UIApplication sharedApplication].keyWindow.rootViewController = [RootViewController new]; [UIView setAnimationsEnabled:oldState]; } completion:^(BOOL finished) { }]; 8、去除数组中重复的对象 NSArray *newArr = [oldArr valueForKeyPath:@“@distinctUnionOfObjects.self"]; 9、编译的时候遇到 no such file or directory: /users/apple/XXX

是因为编译的时候,在此路径下找不到这个文件,解决这个问题,首先是是要检查缺少的文件是不是在工程中,如果不在工程中,需要从本地拖进去,如果发现已经存在工程中了,或者拖进去还是报错,这时候需要去build phases中搜索这个文件,这时候很可能会搜出现两个相同的文件,这时候,有一个路径是正确的,删除另外一个即可。如果删除了还是不行,需要把两个都删掉,然后重新往工程里拖进这个文件即可

iOS 开发经验 - 转载_IOS
build phases 10、iOS8系统中,tableView最好实现下-tableView: heightForRowAtIndexPath:这个代理方法,要不然在iOS8中可能就会出现显示不全或者无法响应事件的问题 11、iOS8中实现侧滑功能的时候这个方法必须实现,要不然在iOS8中无法侧滑 // 必须写的方法,和editActionsForRowAtIndexPath配对使用,里面什么不写也行- (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath {} 12、三个通知

NSSystemTimeZoneDidChangeNotification监听修改时间界面的两个按钮状态变化
UIApplicationSignificantTimeChangeNotification 监听用户改变时间 (只要点击自动设置按钮就会调用) NSSystemClockDidChangeNotification 监听用户修改时间(时间不同才会调用)

13、SDWebImage本地缓存有时候会害人。如果之前缓存过一张图片,即使下次服务器换了这张图片,但是图片url没换,用sdwebimage下载下来的还是以前那张,所以遇到这种问题,不要先去怼服务器,清空下缓存再试就好了。 14、上线前注意:

1)、删掉代码中所有的测试代码
2)、如果后台有审核模式,提醒后台开启此模式
3)、主流程再跑一跑
4)、全局搜索waring,检查所有标记waring的地方

15、跳进app权限设置 // 跳进app设置 if (UIApplicationOpenSettingsURLString != NULL) { UIApplication *application = [UIApplication sharedApplication]; NSURL *URL = [NSURL URLWithString:UIApplicationOpenSettingsURLString];if ([application respondsToSelector:@selector(openURL:options:completionHandler:)]) { [application openURL:URL options:@{} completionHandler:nil]; } else { [application openURL:URL]; } } 16、给一个view截图UIGraphicsBeginImageContextWithOptions(view.bounds.size, YES, 0.0); [view.layer renderInContext:UIGraphicsGetCurrentContext()]; UIImage *img = UIGraphicsGetImageFromCurrentImageContext();UIGraphicsEndImageContext(); 17、开发中如果要动态修改tableView的tableHeaderView或者tableFooterView的高度,需要给tableView重新设置,而不是直接更改高度。正确的做法是重新设置一下tableView.tableFooterView = 更改过高度的view。为什么?其实在iOS8以上直接改高度是没有问题的,在iOS8中出现了contentSize不准确的问题,这是解决办法。 18、注意对象为nil的时候,调用此对象分类的方法不会执行 19、collectionView的内容小于其宽高的时候是不能滚动的,设置可以滚动: collectionView.alwaysBounceHorizontal = YES;collectionView.alwaysBounceVertical = YES; 20、设置navigationBar上的title颜色和大小 [self.navigationController.navigationBar setTitleTextAttributes:@{NSForegroundColorAttributeName : [UIColor youColor], NSFontAttributeName : [UIFont systemFontOfSize:15]}] 21、颜色转图片 + (UIImage *)cl_imageWithColor:(UIColor *)color { CGRect rect = CGRectMake(0.0f, 0.0f, 1.0f, 1.0f); UIGraphicsBeginImageContext(rect.size);CGContextRef context = UIGraphicsGetCurrentContext();CGContextSetFillColorWithColor(context, [color CGColor]);CGContextFillRect(context, rect); UIImage *image = UIGraphicsGetImageFromCurrentImageContext();UIGraphicsEndImageContext(); return image;} 22、view设置圆角 #define ViewBorderRadius(View, Radius, Width, Color)//[View.layer setCornerRadius:(Radius)];/[View.layer setMasksToBounds:YES];/[View.layer setBorderWidth:(Width)];/[View.layer setBorderColor:[Color CGColor]] // view圆角 23、强/弱引用 #define WeakSelf(type) __weak typeof(type) weak##type = type; // weak#define StrongSelf(type) __strong typeof(type) type = weak##type; // strong 24、由角度转换弧度 #define DegreesToRadian(x) (M_PI * (x) / 180.0)25、由弧度转换角度 #define RadianToDegrees(radian) (radian*180.0)/(M_PI)26、获取图片资源 #define GetImage(imageName) [UIImage imageNamed:[NSString stringWithFormat:@"%@",imageName]] 27、获取temp #define PathTemp NSTemporaryDirectory() 28、获取沙盒 Document #define PathDocument [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) firstObject] 29、获取沙盒 Cache #define PathCache [NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES) firstObject] 30、GCD代码只执行一次 #define kDISPATCH_ONCE_BLOCK(onceBlock) static dispatch_once_t onceToken; dispatch_once(&;onceToken, onceBlock); 31、自定义NSLog #ifdef DEBUG#define NSLog(fmt, ...) NSLog((@"%s [Line %d] " fmt), __PRETTY_FUNCTION__, __LINE__, ##__VA_ARGS__)#else#define NSLog(...)#endif 32、Font #define FontL(s) [UIFont systemFontOfSize:s weight:UIFontWeightLight]#define FontR(s) [UIFont systemFontOfSize:s weight:UIFontWeightRegular]#define FontB(s) [UIFont systemFontOfSize:s weight:UIFontWeightBold]#define FontT(s) [UIFont systemFontOfSize:s weight:UIFontWeightThin]#define Font(s) FontL(s) 33、FORMAT #define FORMAT(f, ...) [NSString stringWithFormat:f, ## __VA_ARGS__] 34、在主线程上运行 #define kDISPATCH_MAIN_THREAD(mainQueueBlock) dispatch_async(dispatch_get_main_queue(), mainQueueBlock); 35、开启异步线程 #define kDISPATCH_GLOBAL_QUEUE_DEFAULT(globalQueueBlock) dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), globalQueueBlocl); 36、通知 #define NOTIF_ADD(n, f)[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(f) name:n object:nil]#define NOTIF_POST(n, o) [[NSNotificationCenter defaultCenter] postNotificationName:n object:o]#define NOTIF_REMV()[[NSNotificationCenter defaultCenter] removeObserver:self] 37、随机颜色 + (UIColor *)RandomColor { NSInteger aRedValue = arc4random() % 255;NSInteger aGreenValue = arc4random() % 255; NSInteger aBlueValue = arc4random() % 255; UIColor *randColor = [UIColor colorWithRed:aRedValue / 255.0f green:aGreenValue / 255.0f blue:aBlueValue / 255.0f alpha:1.0f];return randColor;} 38、获取window +(UIWindow*)getWindow { UIWindow* win = nil; //[UIApplication sharedApplication].keyWindow; for (id item in [UIApplication sharedApplication].windows) { if ([item class] == [UIWindow class]) { if (!((UIWindow*)item).hidden) { win = item; break; } } } return win;}39、修改textField的placeholder的字体颜色、大小 [textField setValue:[UIColor redColor] forKeyPath:@"_placeholderLabel.textColor"];[textField setValue:[UIFont boldSystemFontOfSize:16] forKeyPath:@"_placeholderLabel.font"];40、统一收起键盘 [[[UIApplication sharedApplication] keyWindow] endEditing:YES]; 41、控制屏幕旋转,在控制器中写 /** 是否支持自动转屏 */- (BOOL)shouldAutorotate { return YES;}/** 支持哪些屏幕方向 */- (UIInterfaceOrientationMask)supportedInterfaceOrientations { return UIInterfaceOrientationMaskLandscapeLeft | UIInterfaceOrientationMaskLandscapeRight;}/** 默认的屏幕方向(当前ViewController必须是通过模态出来的UIViewController(模态带导航的无效)方式展现出来的,才会调用这个方法) */- (UIInterfaceOrientation)preferredInterfaceOrientationForPresentation { return UIInterfaceOrientationLandscapeLeft | UIInterfaceOrientationLandscapeRight;}42、获取app缓存大小 - (CGFloat)getCachSize { NSUInteger imageCacheSize = [[SDImageCache sharedImageCache] getSize]; //获取自定义缓存大小 //用枚举器遍历一个文件夹的内容 //1.获取文件夹枚举器 NSString *myCachePath = [NSHomeDirectory() stringByAppendingPathComponent:@"Library/Caches"];NSDirectoryEnumerator *enumerator = [[NSFileManager defaultManager] enumeratorAtPath:myCachePath]; __block NSUInteger count = 0; //2.遍历 for (NSString *fileName in enumerator) { NSString *path = [myCachePath stringByAppendingPathComponent:fileName]; NSDictionary *fileDict = [[NSFileManager defaultManager] attributesOfItemAtPath:path error:nil]; count += fileDict.fileSize;//自定义所有缓存大小 } // 得到是字节转化为MCGFloat totalSize = ((CGFloat)imageCacheSize+count)/1024/1024; return totalSize;} 43、清理app缓存 - (void)handleClearView { //删除两部分 //1.删除 sd 图片缓存 //先清除内存中的图片缓存 [[SDImageCache sharedImageCache] clearMemory]; //清除磁盘的缓存 [[SDImageCache sharedImageCache] clearDisk]; //2.删除自己缓存 NSString *myCachePath = [NSHomeDirectory() stringByAppendingPathComponent:@"Library/Caches"]; [[NSFileManager defaultManager] removeItemAtPath:myCachePath error:nil];} 44、模型转字典static NSSet *classes;- (NSMutableDictionary *)getParameterDictionary {NSMutableDictionary *dict = [NSMutableDictionary dictionary]; Class c = self.class; while (c) { unsigned count; objc_property_t *properties = class_copyPropertyList([c class], &;count); for (int i = 0; i < count; i++) {NSString *key = [NSString stringWithUTF8String:property_getName(properties[i])]; dict[key] = [self valueForKey:key]; } free(properties); // 获得父类 c = class_getSuperclass(c); if ([self isClassFromFoundation:c]) break; } return dict;}- (BOOL)isClassFromFoundation:(Class)c{ if (c == [NSObject class] || c == [NSManagedObject class]) return YES; __block BOOL result = NO; [[self foundationClasses] enumerateObjectsUsingBlock:^(Class foundationClass, BOOL *stop) { if ([c isSubclassOfClass:foundationClass]) { result = YES; *stop = YES; } }]; return result;}- (NSSet *)foundationClasses{ if (classes == nil) { // 集合中没有NSObject,因为几乎所有的类都是继承自NSObject,具体是不是NSObject需要特殊判断 classes = [NSSet setWithObjects: [NSURL class], [NSDate class], [NSValue class], [NSData class], [NSError class], [NSArray class], [NSDictionary class], [NSString class], [NSAttributedString class], nil]; }return classes;} 45、交换两个方法实现 Class aClass = [self class]; SEL originalSelector = @selector(viewWillAppear:); SEL swizzledSelector = @selector(xxx_viewWillAppear:); Method originalMethod = class_getInstanceMethod(aClass, originalSelector); Method swizzledMethod = class_getInstanceMethod(aClass, swizzledSelector); BOOL didAddMethod = class_addMethod(aClass, originalSelector, method_getImplementation(swizzledMethod), method_getTypeEncoding(swizzledMethod)); if (didAddMethod) { class_replaceMethod(aClass, swizzledSelector, method_getImplementation(originalMethod), method_getTypeEncoding(originalMethod)); } else { method_exchangeImplementations(originalMethod, swizzledMethod); } 46、打印百分号和引号 NSLog(@"%%"); NSLog(@"/""); 47、几个常用权限判断 if ([CLLocationManager authorizationStatus] ==kCLAuthorizationStatusDenied) { NSLog(@"没有定位权限"); } AVAuthorizationStatus statusVideo = [AVCaptureDevice authorizationStatusForMediaType:AVMediaTypeVideo]; if (statusVideo == AVAuthorizationStatusDenied) { NSLog(@"没有摄像头权限"); }//是否有麦克风权限 AVAuthorizationStatus statusAudio = [AVCaptureDevice authorizationStatusForMediaType:AVMediaTypeAudio]; if (statusAudio == AVAuthorizationStatusDenied) { NSLog(@"没有录音权限"); } [PHPhotoLibrary requestAuthorization:^(PHAuthorizationStatus status) { if (status == PHAuthorizationStatusDenied) { NSLog(@"没有相册权限"); } }]; 48、获取手机型号 + (NSString *)getDeviceInfo { struct utsname systemInfo; uname(&;systemInfo); NSString *platform = [NSString stringWithCString:systemInfo.machine encoding:NSASCIIStringEncoding]; if ([platform isEqualToString:@"iPhone1,1"]) return @"iPhone 2G"; if ([platform isEqualToString:@"iPhone1,2"]) return @"iPhone 3G"; if ([platform isEqualToString:@"iPhone2,1"]) return @"iPhone 3GS"; if ([platform isEqualToString:@"iPhone3,1"]) return @"iPhone 4"; if ([platform isEqualToString:@"iPhone3,2"]) return @"iPhone 4"; if ([platform isEqualToString:@"iPhone3,3"]) return @"iPhone 4"; if ([platform isEqualToString:@"iPhone4,1"]) return @"iPhone 4S"; if ([platform isEqualToString:@"iPhone5,1"]) return @"iPhone 5"; if ([platform isEqualToString:@"iPhone5,2"]) return @"iPhone 5"; if ([platform isEqualToString:@"iPhone5,3"]) return @"iPhone 5c"; if ([platform isEqualToString:@"iPhone5,4"]) return @"iPhone 5c"; if ([platform isEqualToString:@"iPhone6,1"]) return @"iPhone 5s"; if ([platform isEqualToString:@"iPhone6,2"]) return @"iPhone 5s"; if ([platform isEqualToString:@"iPhone7,1"]) return @"iPhone 6 Plus"; if ([platform isEqualToString:@"iPhone7,2"]) return @"iPhone 6"; if ([platform isEqualToString:@"iPhone8,1"]) return @"iPhone 6s"; if ([platform isEqualToString:@"iPhone8,2"]) return @"iPhone 6s Plus"; // 日行两款手机型号均为日本独占,可能使用索尼FeliCa支付方案而不是苹果支付 if ([platform isEqualToString:@"iPhone9,1"]) return @"国行、日版、港行iPhone 7"; if ([platform isEqualToString:@"iPhone9,2"]) return @"港行、国行iPhone 7 Plus";if ([platform isEqualToString:@"iPhone9,3"]) return @"美版、台版iPhone 7"; if ([platform isEqualToString:@"iPhone9,4"]) return @"美版、台版iPhone 7 Plus";if ([platform isEqualToString:@"iPhone8,4"]) return @"iPhone SE"; if ([platform isEqualToString:@"iPod1,1"]) return @"iPod Touch 1G"; if ([platform isEqualToString:@"iPod2,1"]) return @"iPod Touch 2G"; if ([platform isEqualToString:@"iPod3,1"]) return @"iPod Touch 3G"; if ([platform isEqualToString:@"iPod4,1"]) return @"iPod Touch 4G"; if ([platform isEqualToString:@"iPod5,1"]) return @"iPod Touch 5G"; if ([platform isEqualToString:@"iPad1,1"]) return @"iPad 1G"; if ([platform isEqualToString:@"iPad2,1"]) return @"iPad 2"; if ([platform isEqualToString:@"iPad2,2"]) return @"iPad 2"; if ([platform isEqualToString:@"iPad2,3"]) return @"iPad 2"; if ([platform isEqualToString:@"iPad2,4"]) return @"iPad 2"; if ([platform isEqualToString:@"iPad2,5"]) return @"iPad Mini 1G"; if ([platform isEqualToString:@"iPad2,6"]) return @"iPad Mini 1G"; if ([platform isEqualToString:@"iPad2,7"]) return @"iPad Mini 1G"; if ([platform isEqualToString:@"iPad3,1"]) return @"iPad 3"; if ([platform isEqualToString:@"iPad3,2"]) return @"iPad 3"; if ([platform isEqualToString:@"iPad3,3"]) return @"iPad 3"; if ([platform isEqualToString:@"iPad3,4"]) return @"iPad 4"; if ([platform isEqualToString:@"iPad3,5"]) return @"iPad 4"; if ([platform isEqualToString:@"iPad3,6"]) return @"iPad 4"; if ([platform isEqualToString:@"iPad4,1"]) return @"iPad Air"; if ([platform isEqualToString:@"iPad4,2"]) return @"iPad Air"; if ([platform isEqualToString:@"iPad4,3"]) return @"iPad Air"; if ([platform isEqualToString:@"iPad4,4"]) return @"iPad Mini 2G"; if ([platform isEqualToString:@"iPad4,5"]) return @"iPad Mini 2G"; if ([platform isEqualToString:@"iPad4,6"]) return @"iPad Mini 2G"; if ([platform isEqualToString:@"i386"]) return @"iPhone Simulator"; if ([platform isEqualToString:@"x86_64"]) return @"iPhone Simulator"; return platform;}49、长按复制功能 - (void)viewDidLoad{ [self.view addGestureRecognizer:[[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(pasteBoard:)]];}- (void)pasteBoard:(UILongPressGestureRecognizer *)longPress { if (longPress.state == UIGestureRecognizerStateBegan) { UIPasteboard *pasteboard = [UIPasteboard generalPasteboard]; pasteboard.string = @"需要复制的文本"; }}50、cocoapods升级

在终端执行 sudo gem install -n / usr / local / bin cocoapods --pre

51、设置启动页后,依然显示之前的

删除app,手机重启,重新安装

52、判断图片类型 //通过图片Data数据第一个字节来获取图片扩展名- (NSString *)contentTypeForImageData:(NSData *)data{ uint8_t c; [data getBytes:&;c length:1]; switch (c) { case 0xFF: return @"jpeg"; case 0x89:return @"png"; case 0x47: return @"gif"; case 0x49: case 0x4D: return @"tiff"; case 0x52: if ([data length] < 12) { return nil; } NSString *testString = [[NSString alloc] initWithData:[data subdataWithRange:NSMakeRange(0, 12)] encoding:NSASCIIStringEncoding]; if ([testString hasPrefix:@"RIFF"] &;&; [testString hasSuffix:@"WEBP"]) { return @"webp"; } return nil; } return nil;}53、获取手机和app信息 NSDictionary *infoDictionary = [[NSBundle mainBundle] infoDictionary]; CFShow(infoDictionary); // app名称 NSString *app_Name = [infoDictionary objectForKey:@"CFBundleDisplayName"]; // app版本 NSString *app_Version = [infoDictionary objectForKey:@"CFBundleShortVersionString"]; // app build版本 NSString *app_build = [infoDictionary objectForKey:@"CFBundleVersion"]; //手机序列号 NSString* identifierNumber = [[UIDevice currentDevice] uniqueIdentifier];NSLog(@"手机序列号: %@",identifierNumber); //手机别名: 用户定义的名称NSString* userPhoneName = [[UIDevice currentDevice] name]; NSLog(@"手机别名: %@", userPhoneName); //设备名称 NSString* deviceName = [[UIDevice currentDevice] systemName]; NSLog(@"设备名称: %@",deviceName ); //手机系统版本 NSString* phoneVersion = [[UIDevice currentDevice] systemVersion];NSLog(@"手机系统版本: %@", phoneVersion); //手机型号 NSString* phoneModel = [[UIDevice currentDevice] model]; NSLog(@"手机型号: %@",phoneModel ); //地方型号 (国际化区域名称) NSString* localPhoneModel = [[UIDevice currentDevice] localizedModel]; NSLog(@"国际化区域名称: %@",localPhoneModel ); NSDictionary *infoDictionary = [[NSBundle mainBundle] infoDictionary]; // 当前应用名称 NSString *appCurName = [infoDictionary objectForKey:@"CFBundleDisplayName"]; NSLog(@"当前应用名称:%@",appCurName); // 当前应用软件版本比如:1.0.1 NSString *appCurVersion = [infoDictionary objectForKey:@"CFBundleShortVersionString"]; NSLog(@"当前应用软件版本:%@",appCurVersion); // 当前应用版本号码 int类型 NSString *appCurVersionNum = [infoDictionary objectForKey:@"CFBundleVersion"];NSLog(@"当前应用版本号码:%@",appCurVersionNum); 54、获取一个类的所有属性 id LenderClass = objc_getClass("Lender");unsigned int outCount, i;objc_property_t *properties = class_copyPropertyList(LenderClass, &;outCount);for (i = 0; i < outCount; i++) { objc_property_t property = properties[i]; fprintf(stdout, "%s %s/n", property_getName(property), property_getAttributes(property));} 55、image圆角 - (UIImage *)circleImage{// NO代表透明 UIGraphicsBeginImageContextWithOptions(self.size, NO, 1); // 获得上下文 CGContextRef ctx = UIGraphicsGetCurrentContext(); // 添加一个圆 CGRect rect = CGRectMake(0, 0, self.size.width, self.size.height); // 方形变圆形 CGContextAddEllipseInRect(ctx, rect); // 裁剪 CGContextClip(ctx); // 将图片画上去 [self drawInRect:rect]; UIImage *image = UIGraphicsGetImageFromCurrentImageContext();UIGraphicsEndImageContext(); return image;} 56、image拉伸 + (UIImage *)resizableImage:(NSString *)imageName{ UIImage *image = [UIImage imageNamed:imageName]; CGFloat imageW = image.size.width; CGFloat imageH = image.size.height; return [image resizableImageWithCapInsets:UIEdgeInsetsMake(imageH * 0.5, imageW * 0.5, imageH * 0.5, imageW * 0.5) resizingMode:UIImageResizingModeStretch];}57、JSON字符串转字典 + (NSDictionary *)parseJSONStringToNSDictionary:(NSString *)JSONString { NSData *JSONData = [JSONString dataUsingEncoding:NSUTF8StringEncoding]; NSDictionary *responseJSON = [NSJSONSerialization JSONObjectWithData:JSONData options:NSJSONReadingMutableLeaves error:nil]; return responseJSON;} 58、身份证号验证 - (BOOL)validateIdentityCard { BOOL flag; if (self.length <= 0) { flag = NO; return flag; } NSString *regex2 = @"^(//d{14}|//d{17})(//d|[xX])$";NSPredicate *identityCardPredicate = [NSPredicate predicateWithFormat:@"SELF MATCHES %@",regex2]; return [identityCardPredicate evaluateWithObject:self];} 59、获取设备mac地址 + (NSString *)macAddress { int mib[6]; size_t len; char *buf; unsigned char *ptr;struct if_msghdr *ifm; struct sockaddr_dl *sdl; mib[0] = CTL_NET; mib[1] = AF_ROUTE; mib[2] = 0; mib[3] = AF_LINK; mib[4] = NET_RT_IFLIST; if((mib[5] = if_nametoindex("en0")) == 0) { printf("Error: if_nametoindex error/n"); return NULL; } if(sysctl(mib, 6, NULL, &;len, NULL, 0) < 0) { printf("Error: sysctl, take 1/n"); return NULL; } if((buf = malloc(len)) == NULL) { printf("Could not allocate memory. Rrror!/n"); return NULL; } if(sysctl(mib, 6, buf, &;len, NULL, 0) < 0) { printf("Error: sysctl, take 2"); return NULL; } ifm = (struct if_msghdr *)buf; sdl = (struct sockaddr_dl *)(ifm + 1); ptr = (unsigned char *)LLADDR(sdl); NSString *outstring = [NSString stringWithFormat:@"%02X:%02X:%02X:%02X:%02X:%02X", *ptr, *(ptr+1), *(ptr+2), *(ptr+3), *(ptr+4), *(ptr+5)]; free(buf); return outstring;} 60、导入自定义字体库

1、找到你想用的字体的 ttf 格式,拖入工程
2、在工程的plist中增加一行数组,“Fonts provided by application”
3、为这个key添加一个item,value为你刚才导入的ttf文件名
4、直接使用即可:label.font = [UIFont fontWithName:@"你刚才导入的ttf文件名" size:20.0];

61、拿到当前正在显示的控制器,不管是push进去的,还是present进去的都能拿到 - (UIViewController *)getVisibleViewControllerFrom:(UIViewController*)vc { if ([vc isKindOfClass:[UINavigationController class]]) { return [self getVisibleViewControllerFrom:[((UINavigationController*) vc) visibleViewController]]; }else if ([vc isKindOfClass:[UITabBarController class]]){ return [self getVisibleViewControllerFrom:[((UITabBarController*) vc) selectedViewController]]; } else { if (vc.presentedViewController) { return [self getVisibleViewControllerFrom:vc.presentedViewController]; } else { return vc; } }} 62、runtime为一个类动态添加属性 // 动态添加属性的本质是: 让对象的某个属性与值产生关联 objc_setAssociatedObject(self, WZBPlaceholderViewKey, placeholderView, OBJC_ASSOCIATION_RETAIN_NONATOMIC); 63、获取runtime为一个类动态添加的属性 objc_getAssociatedObject(self, WZBPlaceholderViewKey); 64、KVO监听某个对象的属性 // 添加监听者[self addObserver:self forKeyPath:property options:NSKeyValueObservingOptionNew context:nil];// 当监听的属性值变化的时候会来到这个方法- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context { if ([keyPath isEqualToString:@"property"]) { [self textViewTextChange]; } else { }} 65、Reachability判断网络状态 NetworkStatus status = [[Reachability reachabilityForInternetConnection] currentReachabilityStatus]; if (status == NotReachable) { NSLog(@"当前设备无网络"); } if (status == ReachableViaWiFi) { NSLog(@"当前wifi网络"); } if (status == ReachableViaWWAN) { NSLog(@"当前蜂窝移动网络"); } 66、AFNetworking监听网络状态 // 监听网络状况 AFNetworkReachabilityManager *mgr = [AFNetworkReachabilityManager sharedManager]; [mgr setReachabilityStatusChangeBlock:^(AFNetworkReachabilityStatus status) {switch (status) { case AFNetworkReachabilityStatusUnknown: break; case AFNetworkReachabilityStatusNotReachable: { [SVProgressHUD showInfoWithStatus:@"当前设备无网络"]; } break; case AFNetworkReachabilityStatusReachableViaWiFi: [SVProgressHUD showInfoWithStatus:@"当前Wi-Fi网络"]; break; case AFNetworkReachabilityStatusReachableViaWWAN: [SVProgressHUD showInfoWithStatus:@"当前蜂窝移动网络"]; break; default: break; } }]; [mgr startMonitoring]; 67、透明颜色不影响子视图透明度 [UIColor colorWithRed:<#(CGFloat)#> green:<#(CGFloat)#> blue:<#(CGFloat)#> alpha:<#(CGFloat)#>];68、取图片某一点的颜色 if (point.x < 0 || point.y < 0) return nil; CGImageRef imageRef = self.CGImage; NSUInteger width = CGImageGetWidth(imageRef);NSUInteger height = CGImageGetHeight(imageRef); if (point.x >= width || point.y >= height) return nil; unsigned char *rawData = malloc(height * width * 4); if (!rawData) return nil; CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB(); NSUInteger bytesPerPixel = 4; NSUInteger bytesPerRow = bytesPerPixel * width; NSUInteger bitsPerComponent = 8;CGContextRef context = CGBitmapContextCreate(rawData, width, height, bitsPerComponent, bytesPerRow, colorSpace, kCGImageAlphaPremultipliedLast | kCGBitmapByteOrder32Big); if (!context) { free(rawData); return nil; } CGColorSpaceRelease(colorSpace);CGContextDrawImage(context, CGRectMake(0, 0, width, height), imageRef);CGContextRelease(context); int byteIndex = (bytesPerRow * point.y) + point.x * bytesPerPixel; CGFloat red = (rawData[byteIndex] * 1.0) / 255.0; CGFloat green = (rawData[byteIndex + 1] * 1.0) / 255.0; CGFloat blue = (rawData[byteIndex + 2] * 1.0) / 255.0; CGFloat alpha = (rawData[byteIndex + 3] * 1.0) / 255.0; UIColor *result = nil; result = [UIColor colorWithRed:red green:green blue:blue alpha:alpha]; free(rawData); return result; 69、判断该图片是否有透明度通道 - (BOOL)hasAlphaChannel{ CGImageAlphaInfo alpha = CGImageGetAlphaInfo(self.CGImage); return (alpha == kCGImageAlphaFirst ||alpha == kCGImageAlphaLast || alpha == kCGImageAlphaPremultipliedFirst ||alpha == kCGImageAlphaPremultipliedLast);} 70、获得灰度图 + (UIImage*)covertToGrayImageFromImage:(UIImage*)sourceImage{ int width = sourceImage.size.width; int height = sourceImage.size.height;CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceGray();CGContextRef context = CGBitmapContextCreate (nil,width,height,8,0,colorSpace,kCGImageAlphaNone);CGColorSpaceRelease(colorSpace); if (context == NULL) { return nil; }CGContextDrawImage(context,CGRectMake(0, 0, width, height), sourceImage.CGImage); CGImageRef contextRef = CGBitmapContextCreateImage(context); UIImage *grayImage = [UIImage imageWithCGImage:contextRef]; CGContextRelease(context);CGImageRelease(contextRef); return grayImage;} 71、根据bundle中的文件名读取图片 + (UIImage *)imageWithFileName:(NSString *)name { NSString *extension = @"png"; NSArray *components = [name componentsSeparatedByString:@"."]; if ([components count] >= 2) { NSUInteger lastIndex = components.count - 1; extension = [components objectAtIndex:lastIndex]; name = [name substringToIndex:(name.length-(extension.length+1))]; } // 如果为Retina屏幕且存在对应图片,则返回Retina图片,否则查找普通图片 if ([UIScreen mainScreen].scale == 2.0) { name = [name stringByAppendingString:@"@2x"]; NSString *path = [[NSBundle mainBundle] pathForResource:name ofType:extension]; if (path != nil) { return [UIImage imageWithContentsOfFile:path]; } } if ([UIScreen mainScreen].scale == 3.0) {name = [name stringByAppendingString:@"@3x"]; NSString *path = [[NSBundle mainBundle] pathForResource:name ofType:extension]; if (path != nil) { return [UIImage imageWithContentsOfFile:path]; } } NSString *path = [[NSBundle mainBundle] pathForResource:name ofType:extension]; if (path) { return [UIImage imageWithContentsOfFile:path]; } return nil;} 72、合并两个图片 + (UIImage*)mergeImage:(UIImage*)firstImage withImage:(UIImage*)secondImage { CGImageRef firstImageRef = firstImage.CGImage;CGFloat firstWidth = CGImageGetWidth(firstImageRef); CGFloat firstHeight = CGImageGetHeight(firstImageRef); CGImageRef secondImageRef = secondImage.CGImage; CGFloat secondWidth = CGImageGetWidth(secondImageRef); CGFloat secondHeight = CGImageGetHeight(secondImageRef); CGSize mergedSize = CGSizeMake(MAX(firstWidth, secondWidth), MAX(firstHeight, secondHeight));UIGraphicsBeginImageContext(mergedSize); [firstImage drawInRect:CGRectMake(0, 0, firstWidth, firstHeight)]; [secondImage drawInRect:CGRectMake(0, 0, secondWidth, secondHeight)]; UIImage *image = UIGraphicsGetImageFromCurrentImageContext();UIGraphicsEndImageContext(); return image;} 73、根据bundle中的图片名创建imageview + (id)imageViewWithImageNamed:(NSString*)imageName{ return [[UIImageView alloc] initWithImage:[UIImage imageNamed:imageName]];}74、为imageView添加倒影 CGRect frame = self.frame; frame.origin.y += (frame.size.height + 1); UIImageView *reflectionImageView = [[UIImageView alloc] initWithFrame:frame]; self.clipsToBounds = TRUE; reflectionImageView.contentMode = self.contentMode; [reflectionImageView setImage:self.image]; reflectionImageView.transform = CGAffineTransformMakeScale(1.0, -1.0); CALayer *reflectionLayer = [reflectionImageView layer]; CAGradientLayer *gradientLayer = [CAGradientLayer layer]; gradientLayer.bounds = reflectionLayer.bounds; gradientLayer.position = CGPointMake(reflectionLayer.bounds.size.width / 2, reflectionLayer.bounds.size.height * 0.5); gradientLayer.colors = [NSArray arrayWithObjects: (id)[[UIColor clearColor] CGColor], (id)[[UIColor colorWithRed:1.0 green:1.0 blue:1.0 alpha:0.3] CGColor], nil]; gradientLayer.startPoint = CGPointMake(0.5,0.5); gradientLayer.endPoint = CGPointMake(0.5,1.0); reflectionLayer.mask = gradientLayer; [self.superview addSubview:reflectionImageView]; 75、画水印 // 画水印- (void) setImage:(UIImage *)image withWaterMark:(UIImage *)mark inRect:(CGRect)rect{ if ([[[UIDevice currentDevice] systemVersion] floatValue] >= 4.0) {UIGraphicsBeginImageContextWithOptions(self.frame.size, NO, 0.0); } //原图 [image drawInRect:self.bounds]; //水印图 [mark drawInRect:rect]; UIImage *newPic = UIGraphicsGetImageFromCurrentImageContext();UIGraphicsEndImageContext(); self.image = newPic;} 76、让label的文字内容显示在左上/右上/左下/右下/中心顶/中心底部 自定义UILabel// 重写label的textRectForBounds方法- (CGRect)textRectForBounds:(CGRect)bounds limitedToNumberOfLines:(NSInteger)numberOfLines { CGRect rect = [super textRectForBounds:bounds limitedToNumberOfLines:numberOfLines]; switch (self.textAlignmentType) { case WZBTextAlignmentTypeLeftTop: { rect.origin = bounds.origin; } break; case WZBTextAlignmentTypeRightTop: { rect.origin = CGPointMake(CGRectGetMaxX(bounds) - rect.size.width, bounds.origin.y); } break; case WZBTextAlignmentTypeLeftBottom: { rect.origin = CGPointMake(bounds.origin.x, CGRectGetMaxY(bounds) - rect.size.height); }break; case WZBTextAlignmentTypeRightBottom: { rect.origin = CGPointMake(CGRectGetMaxX(bounds) - rect.size.width, CGRectGetMaxY(bounds) - rect.size.height); } break; case WZBTextAlignmentTypeTopCenter: { rect.origin = CGPointMake((CGRectGetWidth(bounds) - CGRectGetWidth(rect)) / 2, CGRectGetMaxY(bounds) - rect.origin.y); } break; case WZBTextAlignmentTypeBottomCenter: { rect.origin = CGPointMake((CGRectGetWidth(bounds) - CGRectGetWidth(rect)) / 2, CGRectGetMaxY(bounds) - CGRectGetMaxY(bounds) - rect.size.height); }break; case WZBTextAlignmentTypeLeft: { rect.origin = CGPointMake(0, rect.origin.y); } break; case WZBTextAlignmentTypeRight: { rect.origin = CGPointMake(rect.origin.x, 0); } break; case WZBTextAlignmentTypeCenter: {rect.origin = CGPointMake((CGRectGetWidth(bounds) - CGRectGetWidth(rect)) / 2, (CGRectGetHeight(bounds) - CGRectGetHeight(rect)) / 2); } break; default: break; } return rect;}- (void)drawTextInRect:(CGRect)rect { CGRect textRect = [self textRectForBounds:rect limitedToNumberOfLines:self.numberOfLines]; [super drawTextInRect:textRect];} 77、scrollView上的输入框,键盘挡住的问题 推荐用IQKeyboardManager这个框架!手动解决如下1、监听键盘弹出/消失的通知2、在通知中加入代码:NSDictionary* info = [aNotification userInfo];CGRect keyPadFrame=[[UIApplication sharedApplication].keyWindow convertRect:[[info objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue] fromView:self.view];CGSize kbSize =keyPadFrame.size;CGRect activeRect=[self.view convertRect:activeField.frame fromView:activeField.superview];CGRect aRect = self.view.bounds;aRect.size.height -= (kbSize.height);CGPoint origin = activeRect.origin;origin.y -= backScrollView.contentOffset.y;if (!CGRectContainsPoint(aRect, origin)) { CGPoint scrollPoint = CGPointMake(0.0,CGRectGetMaxY(activeRect)-(aRect.size.height)); [backScrollView setContentOffset:scrollPoint animated:YES];} 78、frame布局的cell动态高度

这种通常在你的模型中添加一个辅助属性cellHeight,在模型中重写这个属性的get方法,根据你的布局和模型中的其他属性值计算出总高度。最后在tableView:heightForRow方法中,根据indexPath找出对应的模型,返回这个高度即可。

79、AutoLayout布局的cell动态高度 // 1、设置tableView的属性self.tableView.rowHeight = UITableViewAutomaticDimension;self.tableView.estimatedRowHeight = 44.0; // 这个属性非0,估计cell高度 // 2、至上而下设置cell的约束,注意,上下左右最好都要顶到cell的四周 iOS 开发经验 - 转载_IOS
cell 80、使用performSelector:调用函数,内存泄漏问题

当我们在开发中使用[obj performSelector:NSSelectorFromString(@"aMethod")];这类方法时可能会收到一个警告"performSelector may cause a leak because its selector is unknown".
是因为编译器不清楚这个对象能不能相应这个方法,如果不能,则是不安全的,而且编译器也不清楚该怎么处理这个方法的返回值!

使用以下代码调用即可:if (! obj) { return; }SEL selector = NSSelectorFromString(@"aMethod");IMP imp = [obj methodForSelector:selector];void (*func)(id, SEL) = (void *)imp;func(obj, selector);或者:SEL selector = NSSelectorFromString(@"aMethod");((void (*)(id, SEL))[obj methodForSelector:selector])(obj, selector); 81、一个字符串是否包含另一个字符串 // 方法1if ([str1 containsString:str2]) { NSLog(@"str1包含str2"); } else { NSLog(@"str1不包含str2"); }// 方法2if ([str1 rangeOfString: str2].location == NSNotFound) { NSLog(@"str1不包含str2"); } else {NSLog(@"str1包含str2"); } 82、cell去除选中效果 cell.selectionStyle = UITableViewCellSelectionStyleNone; 83、cell点按效果 - (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath { [tableView deselectRowAtIndexPath:indexPath animated:YES];} 84、当删除一个从xib拖出来的属性时,一定记得把xib中对应的线也删掉,不然会报类似[<ViewController 0x7fea6ed05980> setValue:forUndefinedKey:]: this class is not key value coding-compliant for the key的crash iOS 开发经验 - 转载_IOS
点击这个叉号删除 85、真机测试的时候报错:Could not launch "你的 App",process launch failed: Security

因为你的app没有上线,iOS9开始,需要手动信任Xcode生成的描述文件,打开手机设置->通用->描述文件->点击你的app的描述文件->点击信任

86、真机测试的时候报错:Could not find Developer Disk Image

这是因为你的设备系统版本大于Xcode能兼容的系统版本,比如你的设备是iOS10.3,而Xcode版本是8.2(Xcode8.2最大兼容iOS10.2),就会报这个错误。解决办法就是升级Xcode!

87、UITextView没有placeholder的问题?

网上有很多此类自定义控件,也可以参考下我写的一个UITextView分类 UITextView-WZB

88、移除字符串中的空格和换行 + (NSString *)removeSpaceAndNewline:(NSString *)str { NSString *temp = [str stringByReplacingOccurrencesOfString:@" " withString:@""]; temp = [temp stringByReplacingOccurrencesOfString:@"/r" withString:@""]; temp = [temp stringByReplacingOccurrencesOfString:@"/n" withString:@""]; return temp;}89、判断字符串中是否有空格 + (BOOL)isBlank:(NSString *)str { NSRange _range = [str rangeOfString:@" "]; if (_range.location != NSNotFound) { //有空格 return YES; } else { //没有空格 return NO; }} 90、获取一个视频的第一帧图片NSURL *url = [NSURL URLWithString:filepath]; AVURLAsset *asset1 = [[AVURLAsset alloc] initWithURL:url options:nil]; AVAssetImageGenerator *generate1 = [[AVAssetImageGenerator alloc] initWithAsset:asset1]; generate1.appliesPreferredTrackTransform = YES; NSError *err = NULL;CMTime time = CMTimeMake(1, 2); CGImageRef oneRef = [generate1 copyCGImageAtTime:time actualTime:NULL error:&;err]; UIImage *one = [[UIImage alloc] initWithCGImage:oneRef]; return one; 91、获取视频的时长 + (NSInteger)getVideoTimeByUrlString:(NSString *)urlString { NSURL *videoUrl = [NSURL URLWithString:urlString]; AVURLAsset *avUrl = [AVURLAsset assetWithURL:videoUrl]; CMTime time = [avUrl duration]; int seconds = ceil(time.value/time.timescale); return seconds;} 92、字符串是否为空 + (BOOL)isEqualToNil:(NSString *)str { return str.length <= 0 || [str isEqualToString:@""] || !str;} 93、将app上传到App Store的时候通常会遇到这个问题 iOS 开发经验 - 转载_IOS
try again

很多人说这事苹果爸爸服务器问题,重复尝试几次,总会成功的!
但是经过尝试发现如果使用Application Loader上传成功率就非常高,所以还是推荐把ipa文件导出直接用Application Loader上传。
如果Application Loader也不行,需要检查下自己的网络,有时候vpn也会提高速度。

94、当tableView占不满一屏时,去除下边多余的单元格self.tableView.tableHeaderView = [UIView new];self.tableView.tableFooterView = [UIView new]; 95、isKindOfClass和isMemberOfClass的区别 isKindOfClass可以判断某个对象是否属于某个类,或者这个类的子类。isMemberOfClass更加精准,它只能判断这个对象类型是否为这个类(不能判断子类) 96、__block

当一个局部变量需要在block里改变时,需要在定义时加上__block修饰,具体请看官方文档 http://developer.apple.com/library/ios/documentation/cocoa/Conceptual/Blocks/Articles/bxVariables.html#//apple_ref/doc/uid/TP40007502-CH6-SW6

97、-[ViewController aMethod:]: unrecognized selector sent to instance 0x7fe91e607fb0

这是一个经典错误,ViewController不能响应aMethod这个方法,错误原因可能viewController文件中没有实现aMethod这个方法

98、UITableView (<UITableView: 0x7ff19b027000; >) failed to obtain a cell from its dataSource (<ViewController: 0x7ff19a507520>)

这个错误原因是tableView的代理方法-tableView:cellForRowAtIndexPath:需要返回一个UITableViewCell,而你返回了一个nil。另外这个地方返回值不是UITableViewCell类型也会导致崩溃

99、约束如何做UIView动画? 1、把需要改的约束Constraint拖条线出来,成为属性2、在需要动画的地方加入代码,改变此属性的constant属性3、开始做UIView动画,动画里边调用layoutIfNeeded方法@property (weak, nonatomic) IBOutlet NSLayoutConstraint *buttonTopConstraint;self.buttonTopConstraint.constant = 100; [UIView animateWithDuration:.5 animations:^{ [self.view layoutIfNeeded]; }]; 100、从NSURL中拿到链接字符串 NSString *urlString = myURL.absoluteString; 101、将tableView滚动到顶部 [tableView setContentOffset:CGPointZero animated:YES];或者[tableView scrollRectToVisible:CGRectMake(0, 0, 1, 1) animated:YES]; 102、如果用addTarget:action:forControlEvents:方法为一个button添加了很多点击事件,在某个时刻想一次删除怎么办?只需要调用下边这句代码 [youButton removeTarget:nil action:nil forControlEvents:UIControlEventAllEvents]; 103、某个字体的高度font.lineHeight; 104、删除某个view所有的子视图 [[someView subviews] makeObjectsPerformSelector:@selector(removeFromSuperview)]; 105、删除NSUserDefaults所有记录 //方法一 NSString *appDomain = [[NSBundle mainBundle] bundleIdentifier]; [[NSUserDefaults standardUserDefaults] removePersistentDomainForName:appDomain]; //方法二 - (void)resetDefaults { NSUserDefaults * defs = [NSUserDefaults standardUserDefaults];NSDictionary * dict = [defs dictionaryRepresentation]; for (id key in dict) { [defs removeObjectForKey:key]; } [defs synchronize]; }// 方法三[[NSUserDefaults standardUserDefaults] setPersistentDomain:[NSDictionary dictionary] forName:[[NSBundle mainBundle] bundleIdentifier]]; 106、禁用系统滑动返回功能 - (void)viewDidAppear:(BOOL)animated{ [super viewDidAppear:animated];if ([self.navigationController respondsToSelector:@selector(interactivePopGestureRecognizer)]) {self.navigationController.interactivePopGestureRecognizer.delegate = self; }}- (void)viewWillDisappear:(BOOL)animated { [super viewWillDisappear:animated]; if ([self.navigationController respondsToSelector:@selector(interactivePopGestureRecognizer)]) {self.navigationController.interactivePopGestureRecognizer.delegate = nil; }}- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer{ return NO;} 107、模拟器报错 iOS 开发经验 - 转载_IOS
模拟器报错

解决办法:
打开模拟器->Simulator->Reset Content and Settings...
如果不行,就重启试试!

108、自定义cell选中背景颜色 UIView *bgColorView = [[UIView alloc] init];bgColorView.backgroundColor = [UIColor redColor];[cell setSelectedBackgroundView:bgColorView]; 109、UILabel设置内边距 子类化UILabel,重写drawTextInRect方法- (void)drawTextInRect:(CGRect)rect { // 边距,上左下右 UIEdgeInsets insets = {0, 5, 0, 5}; [super drawTextInRect:UIEdgeInsetsInsetRect(rect, insets)];} 110、UILabel设置文字描边 子类化UILabel,重写drawTextInRect方法- (void)drawTextInRect:(CGRect)rect{ CGContextRef c = UIGraphicsGetCurrentContext(); // 设置描边宽度 CGContextSetLineWidth(c, 1); CGContextSetLineJoin(c, kCGLineJoinRound); CGContextSetTextDrawingMode(c, kCGTextStroke); // 描边颜色 self.textColor = [UIColor redColor]; [super drawTextInRect:rect]; // 文本颜色 self.textColor = [UIColor yellowColor];CGContextSetTextDrawingMode(c, kCGTextFill); [super drawTextInRect:rect];}111、使用模拟器截图

快捷键command + s
或者File->Save Screen Shot

112、scrollView滚动到最下边 CGPoint bottomOffset = CGPointMake(0, scrollView.contentSize.height - scrollView.bounds.size.height);[scrollView setContentOffset:bottomOffset animated:YES]; 113、UIView背景颜色渐变UIView *view = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 320, 100)]; [self.view addSubview:view]; CAGradientLayer *gradient = [CAGradientLayer layer]; gradient.frame = view.bounds; gradient.colors = [NSArray arrayWithObjects:(id)[[UIColor blackColor] CGColor], (id)[[UIColor whiteColor] CGColor], nil]; [view.layer insertSublayer:gradient atIndex:0]; 114、停止UIView动画 [yourView.layer removeAllAnimations] 115、为UIView某个角添加圆角 // 左上角和右下角添加圆角UIBezierPath *maskPath = [UIBezierPath bezierPathWithRoundedRect:view.bounds byRoundingCorners:(UIRectCornerTopLeft | UIRectCornerBottomRight) cornerRadii:CGSizeMake(20, 20)]; CAShapeLayer *maskLayer = [CAShapeLayer layer]; maskLayer.frame = view.bounds; maskLayer.path = maskPath.CGPath; view.layer.mask = maskLayer; 116、删除Xcode Derived data缓存数据

依次点击Xcode -> Preferences -> location,然后点击 Derived data路径后到小箭头,删除这个文件夹下的数据就可以了,如图

Xcode Derived data

117、将一个view放置在其兄弟视图的最上面 [parentView bringSubviewToFront:yourView] 118、将一个view放置在其兄弟视图的最下面[parentView sendSubviewToBack:yourView] 119、让手机震动一下 倒入框架#import <AudioToolbox/AudioToolbox.h>AudioServicesPlayAlertSound(kSystemSoundID_Vibrate);或者AudioServicesPlaySystemSound(kSystemSoundID_Vibrate);120、layoutSubviews方法什么时候调用?

1、init方法不会调用
2、addSubview方法等时候会调用
3、bounds改变的时候调用
4、scrollView滚动的时候会调用scrollView的layoutSubviews方法(所以不建议在scrollView的layoutSubviews方法中做复杂逻辑)
5、旋转设备的时候调用
6、子视图被移除的时候调用
参考请看:http://blog.logichigh.com/2011/03/16/when-does-layoutsubviews-get-called/

121、让UILabel在指定的地方换行 // 换行符为/n,在需要换行的地方加上这个符号即可,如 label.numberOfLines = 0;label.text = @"此处/n换行"; 122、摇一摇功能1、打开摇一摇功能 [UIApplication sharedApplication].applicationSupportsShakeToEdit = YES;2、让需要摇动的控制器成为第一响应者[self becomeFirstResponder];3、实现以下方法// 开始摇动- (void)motionBegan:(UIEventSubtype)motion withEvent:(UIEvent *)event// 取消摇动- (void)motionCancelled:(UIEventSubtype)motion withEvent:(UIEvent *)event// 摇动结束- (void)motionEnded:(UIEventSubtype)motion withEvent:(UIEvent *)event 123、获取图片大小 CGFloat imageWidth = image.size.width; CGFloat imageHeight = imageWidth * image.scale; 124、获取view的坐标在整个window上的位置 // v上的(0, 0)点在toView上的位置CGPoint point = [v convertPoint:CGPointMake(0, 0) toView:[UIApplication sharedApplication].windows.lastObject];或者CGPoint point = [v.superview convertPoint:v.frame.origin toView:[UIApplication sharedApplication].windows.lastObject]; 125、提交App Store审核程序限制

您的应用程序的未压缩大小必须小于4GB。每个Mach-O可执行文件(例如app_name.app/app_name)不能超过这些限制:
对于MinimumOSVersion小于7.0的应用程序:TEXT二进制文件中所有部分的总数最多为80 MB 。
对于MinimumOSVersion7.x到8.x的应用程序:TEXT对于二进制文件中每个体系结构片段的每个片段,最大为60 MB 。
对于MinimumOSVersion9.0或更高版本的应用程序:__TEXT二进制文件中所有部分的总数最多为500 MB 。参阅:iTunes Connect开发者指南

126、修改UISegmentedControl的字体大小 [segment setTitleTextAttributes:@{NSFontAttributeName : [UIFont systemFontOfSize:15.0f]} forState:UIControlStateNormal]; 127、在非ViewController的地方弹出UIAlertController对话框 // 最好抽成一个分类UIAlertController *alertController = [UIAlertController alertControllerWithTitle:@"Title" message:@"message" preferredStyle:UIAlertControllerStyleAlert];//...id rootViewController = [UIApplication sharedApplication].delegate.window.rootViewController;if([rootViewController isKindOfClass:[UINavigationController class]]){ rootViewController = ((UINavigationController *)rootViewController).viewControllers.firstObject;}if([rootViewController isKindOfClass:[UITabBarController class]]){ rootViewController = ((UITabBarController *)rootViewController).selectedViewController;}[rootViewController presentViewController:alertController animated:YES completion:nil]; 128、获取一个view所属的控制器 // view分类方法- (UIViewController *)belongViewController { for (UIView *next = [self superview]; next; next = next.superview) { UIResponder* nextResponder = [next nextResponder]; if ([nextResponder isKindOfClass:[UIViewController class]]) { return (UIViewController *)nextResponder; } } return nil;} 129、UIImage和base64互转 // view分类方法- (NSString *)encodeToBase64String:(UIImage *)image { return [UIImagePNGRepresentation(image) base64EncodedStringWithOptions:NSDataBase64Encoding64CharacterLineLength];}- (UIImage *)decodeBase64ToImage:(NSString *)strEncodeData {NSData *data = [[NSData alloc]initWithBase64EncodedString:strEncodeData options:NSDataBase64DecodingIgnoreUnknownCharacters]; return [UIImage imageWithData:data];} 130、UIWebView设置背景透明 [webView setBackgroundColor:[UIColor clearColor]];[webView setOpaque:NO]; 131、判断NSDate是不是今天 NSDateComponents *otherDay = [[NSCalendar currentCalendar] components:NSCalendarUnitEra | NSCalendarUnitYear | NSCalendarUnitMonth | NSCalendarUnitDay fromDate:aDate];NSDateComponents *today = [[NSCalendar currentCalendar] components:NSCalendarUnitEra | NSCalendarUnitYear | NSCalendarUnitMonth | NSCalendarUnitDay fromDate:[NSDate date]];if([today day] == [otherDay day] &;&; [today month] == [otherDay month] &;&; [today year] == [otherDay year] &;&; [today era] == [otherDay era]) { // 是今天}132、设置tableView分割线颜色 [self.tableView setSeparatorColor:[UIColor myColor]]; 133、设置屏幕方向 NSNumber *orientationTarget = [NSNumber numberWithInt:UIInterfaceOrientationLandscapeLeft];[[UIDevice currentDevice] setValue:orientationTarget forKey:@"orientation"];[UIViewController attemptRotationToDeviceOrientation]; 134、比较两个颜色是否相等 - (BOOL)isEqualToColor:(UIColor *)otherColor { CGColorSpaceRef colorSpaceRGB = CGColorSpaceCreateDeviceRGB(); UIColor *(^convertColorToRGBSpace)(UIColor*) = ^(UIColor *color) { if (CGColorSpaceGetModel(CGColorGetColorSpace(color.CGColor)) == kCGColorSpaceModelMonochrome) { const CGFloat *oldComponents = CGColorGetComponents(color.CGColor); CGFloat components[4] = {oldComponents[0], oldComponents[0], oldComponents[0], oldComponents[1]}; CGColorRef colorRef = CGColorCreate( colorSpaceRGB, components ); UIColor *color = [UIColor colorWithCGColor:colorRef];CGColorRelease(colorRef); return color; } else return color; }; UIColor *selfColor = convertColorToRGBSpace(self); otherColor = convertColorToRGBSpace(otherColor);CGColorSpaceRelease(colorSpaceRGB); return [selfColor isEqual:otherColor];} 135、tableViewCell分割线顶到头 - (void)tableView:(UITableView *)tableView willDisplayCell:(UITableViewCell *)cell forRowAtIndexPath:(NSIndexPath *)indexPath { [cell setSeparatorInset:UIEdgeInsetsZero]; [cell setLayoutMargins:UIEdgeInsetsZero]; cell.preservesSuperviewLayoutMargins = NO;}- (void)viewDidLayoutSubviews { [self.tableView setSeparatorInset:UIEdgeInsetsZero]; [self.tableView setLayoutMargins:UIEdgeInsetsZero];} 136、不让控制器的view随着控制器的xib拉伸或压缩 self.view.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight; 137、cocoaPods报错 : [!] Unable to add a source with url https://github.com/CocoaPods/Specs.git named master-1.

You can try adding it manually in ~/.cocoapods/repos or via pod repo add.

解决方法:这是因为电脑里安装了另外一个Xcode导致cocoapods找不到路径了
在终端执行 sudo xcode-select -switch /Applications/Xcode.app 即可

138、安装cocoapods的时候出现 ERROR: While executing gem ... (Errno::EPERM) Operation not permitted - /usr/bin/pod

解决办法:直接在终端执行 sudo gem install -n /usr/local/bin cocoapods

139、在状态栏增加网络请求的菊花,类似safari加载网页的时候状态栏菊花[UIApplication sharedApplication].networkActivityIndicatorVisible = YES; 140、检查一个rect是否包含一个point // point是否在rect内BOOL isContains = CGRectContainsPoint(rect, point); 141、在指定的宽度下,让UILabel自动设置最佳font label.adjustsFontSizeToFitWidth = YES; 142、将一个image保存在相册中 UIImageWriteToSavedPhotosAlbum(image, nil, nil, nil);或者#import <Photos/Photos.h>[[PHPhotoLibrary sharedPhotoLibrary] performChanges:^{ PHAssetChangeRequest *changeRequest = [PHAssetChangeRequest creationRequestForAssetFromImage:image]; changeRequest.creationDate = [NSDate date]; } completionHandler:^(BOOL success, NSError *error) { if (success) { NSLog(@"successfully saved"); } else { NSLog(@"error saving to photos: %@", error); } }]; 143、修改cell.imageView的大小 UIImage *icon = [UIImage imageNamed:@""];CGSize itemSize = CGSizeMake(30, 30);UIGraphicsBeginImageContextWithOptions(itemSize, NO ,0.0);CGRect imageRect = CGRectMake(0.0, 0.0, itemSize.width, itemSize.height);[icon drawInRect:imageRect];cell.imageView.image = UIGraphicsGetImageFromCurrentImageContext();UIGraphicsEndImageContext(); 144、为一个view添加虚线边框 CAShapeLayer *border = [CAShapeLayer layer]; border.strokeColor = [UIColor colorWithRed:67/255.0f green:37/255.0f blue:83/255.0f alpha:1].CGColor; border.fillColor = nil; border.lineDashPattern = @[@4, @2]; border.path = [UIBezierPath bezierPathWithRect:view.bounds].CGPath; border.frame = view.bounds; [view.layer addSublayer:border]; 145、UITextView中打开或禁用复制,剪切,选择,全选等功能 // 继承UITextView重写这个方法- (BOOL)canPerformAction:(SEL)action withSender:(id)sender{// 返回NO为禁用,YES为开启 // 粘贴 if (action == @selector(paste:)) return NO; // 剪切 if (action == @selector(cut:)) return NO; // 复制 if (action == @selector(copy:)) return NO; // 选择 if (action == @selector(select:)) return NO; // 选中全部 if (action == @selector(selectAll:)) return NO; // 删除 if (action == @selector(delete:)) return NO; // 分享 if (action == @selector(share)) return NO; return [super canPerformAction:action withSender:sender];} 1、设置UILabel行间距NSMutableAttributedString* attrString = [[NSMutableAttributedString alloc] initWithString:label.text]; NSMutableParagraphStyle *style = [[NSMutableParagraphStyle alloc] init]; [style setLineSpacing:20]; [attrString addAttribute:NSParagraphStyleAttributeName value:style range:NSMakeRange(0, label.text.length)]; label.attributedText = attrString;

// 或者使用xib,看下gif图

Untitled.gif

2、当使用-performSelector:withObject:withObject:afterDelay:方法时,需要传入多参数问题 // 方法一、// 把参数放进一个数组/字典,直接把数组/字典当成一个参数传过去,具体方法实现的地方再解析这个数组/字典NSArray * array = [NSArray arrayWithObjects: @"first", @"second", nil];[self performSelector:@selector(fooFirstInput:) withObject: array afterDelay:15.0];// 方法二、// 使用NSInvocationSEL aSelector = NSSelectorFromString(@"doSoming:argument2:"); NSInteger argument1 = 10; NSString *argument2 = @"argument2"; if([self respondsToSelector:aSelector]) { NSInvocation *inv = [NSInvocation invocationWithMethodSignature:[self methodSignatureForSelector:aSelector]]; [inv setSelector:aSelector]; [inv setTarget:self]; [inv setArgument:&;(argument1) atIndex:2]; [inv setArgument:&;(argument2) atIndex:3]; [inv performSelector:@selector(invoke) withObject:nil afterDelay:15.0]; } 3、UILabel显示不同颜色字体 NSMutableAttributedString * string = [[NSMutableAttributedString alloc] initWithString:label.text];[string addAttribute:NSForegroundColorAttributeName value:[UIColor redColor] range:NSMakeRange(0,5)];[string addAttribute:NSForegroundColorAttributeName value:[UIColor greenColor] range:NSMakeRange(5,6)];[string addAttribute:NSForegroundColorAttributeName value:[UIColor blueColor] range:NSMakeRange(11,5)];label.attributedText = string; 4、比较两个CGRect/CGSize/CGPoint是否相等 if (CGRectEqualToRect(rect1, rect2)) { // 两个区域相等 // do some } if (CGPointEqualToPoint(point1, point2)) { // 两个点相等 // do some } if (CGSizeEqualToSize(size1, size2)) { // 两个size相等 // do some } 5、比较两个NSDate相差多少小时 NSDate* date1 = someDate; NSDate* date2 = someOtherDate; NSTimeInterval distanceBetweenDates = [date1 timeIntervalSinceDate:date2]; double secondsInAnHour = 3600;// 除以3600是把秒化成小时,除以60得到结果为相差的分钟数 NSInteger hoursBetweenDates = distanceBetweenDates / secondsInAnHour; 6、每个cell之间增加间距 // 方法一,每个分区只显示一行cell,分区头当作你想要的间距(注意,从数据源数组中取值的时候需要用indexPath.section而不是indexPath.row)- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView{ return yourArry.count;}- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section{ return 1;}-(CGFloat)tableView:(UITableView *)tableView heightForHeaderInSection:(NSInteger)section{ return cellSpacingHeight;}// 方法二,在cell的contentView上加个稍微低一点的view,cell上原本的内容放在你的view上,而不是contentView上,这样能伪造出一个间距来。// 方法三,自定义cell,重写setFrame:方法- (void)setFrame:(CGRect)frame{ frame.size.height -= 20; [super setFrame:frame];} 7、播放一张张连续的图片 // 加入现在有三张图片分别为animate_1、animate_2、animate_3// 方法一 imageView.animationImages = @[[UIImage imageNamed:@"animate_1"], [UIImage imageNamed:@"animate_2"], [UIImage imageNamed:@"animate_3"]];imageView.animationDuration = 1.0;// 方法二 imageView.image = [UIImage animatedImageNamed:@"animate_" duration:1.0];// 方法二解释下,这个方法会加载animate_为前缀的,后边0-1024,也就是animate_0、animate_1一直到animate_1024 8、加载gif图片

推荐使用这个框架 FLAnimatedImage

9、防止离屏渲染为image添加圆角 // image分类- (UIImage *)circleImage{// NO代表透明UIGraphicsBeginImageContextWithOptions(self.size, NO, 1);// 获得上下文CGContextRef ctx = UIGraphicsGetCurrentContext();// 添加一个圆CGRect rect = CGRectMake(0, 0, self.size.width, self.size.height);// 方形变圆形CGContextAddEllipseInRect(ctx, rect);// 裁剪CGContextClip(ctx);// 将图片画上去[self drawInRect:rect];UIImage *image = UIGraphicsGetImageFromCurrentImageContext();UIGraphicsEndImageContext();return image;} 10、查看系统所有字体 // 打印字体for (id familyName in [UIFont familyNames]) { NSLog(@"%@", familyName); for (id fontName in [UIFont fontNamesForFamilyName:familyName]) NSLog(@" %@", fontName);}// 也可以进入这个网址查看 http://iosfonts.com/ 11、获取随机数NSInteger i = arc4random(); 12、获取随机数小数(0-1之间) #define ARC4RANDOM_MAX 0x100000000double val = ((double)arc4random() / ARC4RANDOM_MAX); 13、AVPlayer视频播放完成的通知监听[[NSNotificationCenter defaultCenter] addObserver:selfselector:@selector(videoPlayEnd) name:AVPlayerItemDidPlayToEndTimeNotification object:nil]; 14、判断两个rect是否有交叉 if (CGRectIntersectsRect(rect1, rect2)) {} 15、判断一个字符串是否为数字 NSCharacterSet *notDigits = [[NSCharacterSet decimalDigitCharacterSet] invertedSet]; if ([str rangeOfCharacterFromSet:notDigits].location == NSNotFound) { // 是数字 } else { // 不是数字 } 16、将一个view保存为pdf格式 - (void)createPDFfromUIView:(UIView*)aView saveToDocumentsWithFileName:(NSString*)aFilename{ NSMutableData *pdfData = [NSMutableData data];UIGraphicsBeginPDFContextToData(pdfData, aView.bounds, nil);UIGraphicsBeginPDFPage(); CGContextRef pdfContext = UIGraphicsGetCurrentContext(); [aView.layer renderInContext:pdfContext];UIGraphicsEndPDFContext(); NSArray* documentDirectories = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask,YES); NSString* documentDirectory = [documentDirectories objectAtIndex:0]; NSString* documentDirectoryFilename = [documentDirectory stringByAppendingPathComponent:aFilename]; [pdfData writeToFile:documentDirectoryFilename atomically:YES];NSLog(@"documentDirectoryFileName: %@",documentDirectoryFilename);}17、让一个view在父视图中心 child.center = [parent convertPoint:parent.center fromView:parent.superview]; 18、获取当前导航控制器下前一个控制器 - (UIViewController *)backViewController{ NSInteger myIndex = [self.navigationController.viewControllers indexOfObject:self]; if ( myIndex != 0 &;&; myIndex != NSNotFound ) { return [self.navigationController.viewControllers objectAtIndex:myIndex-1]; } else {return nil; }} 19、保存UIImage到本地 NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);NSString *filePath = [[paths objectAtIndex:0] stringByAppendingPathComponent:@"Image.png"];[UIImagePNGRepresentation(image) writeToFile:filePath atomically:YES]; 20、键盘上方增加工具栏 UIToolbar *keyboardDoneButtonView = [[UIToolbar alloc] init];[keyboardDoneButtonView sizeToFit];UIBarButtonItem *doneButton = [[UIBarButtonItem alloc] initWithTitle:@"Done" style:UIBarButtonItemStyleBordered target:self action:@selector(doneClicked:)];[keyboardDoneButtonView setItems:[NSArray arrayWithObjects:doneButton, nil]];txtField.inputAccessoryView = keyboardDoneButtonView; 21、copy一个view

因为UIView没有实现copy协议,因此找不到copyWithZone方法,使用copy的时候导致崩溃
但是我们可以通过归档再解档实现copy,这相当于对视图进行了一次深拷贝,代码如下

id copyOfView = [NSKeyedUnarchiver unarchiveObjectWithData:[NSKeyedArchiver archivedDataWithRootObject:originalView]]; 22、在image上绘制文字并生成新的image UIFont *font = [UIFont boldSystemFontOfSize:12]; UIGraphicsBeginImageContext(image.size); [image drawInRect:CGRectMake(0,0,image.size.width,image.size.height)]; CGRect rect = CGRectMake(point.x, point.y, image.size.width, image.size.height); [[UIColor whiteColor] set]; [text drawInRect:CGRectIntegral(rect) withFont:font]; UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext(); 23、判断一个view是否为另一个view的子视图 // 如果myView是self.view本身,也会返回yesBOOL isSubView = [myView isDescendantOfView:self.view]; 24、判断一个字符串是否包含另一个字符串 // 方法一、这种方法只适用于iOS8之后,如果是配iOS8之前用方法二if ([str containsString:otherStr]) NSLog(@"包含");// 方法二NSRange range = [str rangeOfString:otherStr];if (range.location != NSNotFound) NSLog(@"包含");25、UICollectionView自动滚动到某行 // 重写viewDidLayoutSubviews方法-(void)viewDidLayoutSubviews { [super viewDidLayoutSubviews]; [self.collectionView scrollToItemAtIndexPath:indexPath atScrollPosition:UICollectionViewScrollPositionCenteredVertically animated:NO];} 26、修改系统UIAlertController // 但是据说这种方法会被App Store拒绝(慎用!)UIAlertController *alertVC = [UIAlertController alertControllerWithTitle:@"" message:@"" preferredStyle:UIAlertControllerStyleActionSheet]; NSMutableAttributedString *hogan = [[NSMutableAttributedString alloc] initWithString:@"我是一个大文本"]; [hogan addAttribute:NSFontAttributeName value:[UIFont systemFontOfSize:30] range:NSMakeRange(4, 1)]; [hogan addAttribute:NSForegroundColorAttributeName value:[UIColor redColor] range:NSMakeRange(4, 1)]; [alertVC setValue:hogan forKey:@"attributedTitle"]; UIAlertAction *button = [UIAlertAction actionWithTitle:@"Label text" style:UIAlertActionStyleDefault handler:^(UIAlertAction *action){ }]; UIImage *accessoryImage = [UIImage imageNamed:@"1"]; [button setValue:accessoryImage forKey:@"image"]; [alertVC addAction:button]; [self presentViewController:alertVC animated:YES completion:nil]; 27、判断某一行的cell是否已经显示 CGRect cellRect = [tableView rectForRowAtIndexPath:indexPath];BOOL completelyVisible = CGRectContainsRect(tableView.bounds, cellRect); 28、让导航控制器pop回指定的控制器 NSMutableArray *allViewControllers = [NSMutableArray arrayWithArray:[self.navigationController viewControllers]];for (UIViewController *aViewController in allViewControllers) { if ([aViewController isKindOfClass:[RequiredViewController class]]) { [self.navigationController popToViewController:aViewController animated:NO]; }} 29、动画修改label上的文字 // 方法一CATransition *animation = [CATransition animation]; animation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut]; animation.type = kCATransitionFade; animation.duration = 0.75; [self.label.layer addAnimation:animation forKey:@"kCATransitionFade"]; self.label.text = @"New";// 方法二[UIView transitionWithView:self.label duration:0.25f options:UIViewAnimationOptionTransitionCrossDissolve animations:^{self.label.text = @"Well done!"; } completion:nil];// 方法三[UIView animateWithDuration:1.0 animations:^{ self.label.alpha = 0.0f; self.label.text = @"newText"; self.label.alpha = 1.0f; }]; 30、判断字典中是否包含某个key值 if ([dic objectForKey:@"yourKey"]) { NSLog(@"有这个值");} else { NSLog(@"没有这个值");} 31、获取屏幕方向 UIInterfaceOrientation orientation = [UIApplication sharedApplication].statusBarOrientation;if(orientation == 0) //Default orientation //默认else if(orientation == UIInterfaceOrientationPortrait) //竖屏else if(orientation == UIInterfaceOrientationLandscapeLeft) // 左横屏else if(orientation == UIInterfaceOrientationLandscapeRight) //右横屏 32、设置UIImage的透明度 // 方法一、添加UIImage分类- (UIImage *)imageByApplyingAlpha:(CGFloat) alpha {UIGraphicsBeginImageContextWithOptions(self.size, NO, 0.0f); CGContextRef ctx = UIGraphicsGetCurrentContext(); CGRect area = CGRectMake(0, 0, self.size.width, self.size.height); CGContextScaleCTM(ctx, 1, -1);CGContextTranslateCTM(ctx, 0, -area.size.height);CGContextSetBlendMode(ctx, kCGBlendModeMultiply);CGContextSetAlpha(ctx, alpha); CGContextDrawImage(ctx, area, self.CGImage); UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();UIGraphicsEndImageContext(); return newImage;}// 方法二、如果没有奇葩需求,干脆用UIImageView设置透明度UIImageView *imageView = [[UIImageView alloc] initWithImage:[UIImage imageWithName:@"yourImage"]];imageView.alpha = 0.5; 33、Attempt to mutate immutable object with insertString:atIndex:

这个错是因为你拿字符串调用insertString:atIndex:方法的时候,调用对象不是NSMutableString,应该先转成这个类型再调用

34、UIWebView添加单击手势不响应 UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(webViewClick)]; tap.delegate = self; [_webView addGestureRecognizer:tap];// 因为webView本身有一个单击手势,所以再添加会造成手势冲突,从而不响应。需要绑定手势代理,并实现下边的代理方法- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer{ return YES;} 35、获取手机RAM容量 // 需要导入#import <mach/mach.h>mach_port_t host_port; mach_msg_type_number_t host_size; vm_size_t pagesize; host_port = mach_host_self(); host_size = sizeof(vm_statistics_data_t) / sizeof(integer_t); host_page_size(host_port, &;pagesize); vm_statistics_data_t vm_stat; if (host_statistics(host_port, HOST_VM_INFO, (host_info_t)&;vm_stat, &;host_size) != KERN_SUCCESS) { NSLog(@"Failed to fetch vm statistics"); } /* Stats in bytes */ natural_t mem_used = (vm_stat.active_count + vm_stat.inactive_count + vm_stat.wire_count) * pagesize; natural_t mem_free = vm_stat.free_count * pagesize; natural_t mem_total = mem_used + mem_free; NSLog(@"已用: %u 可用: %u 总共: %u", mem_used, mem_free, mem_total); 36、地图上两个点之间的实际距离 // 需要导入#import <CoreLocation/CoreLocation.h>CLLocation *locA = [[CLLocation alloc] initWithLatitude:34 longitude:113]; CLLocation *locB = [[CLLocation alloc] initWithLatitude:31.05 longitude:121.76];// CLLocationDistance求出的单位为米 CLLocationDistance distance = [locA distanceFromLocation:locB]; 37、在应用中打开设置的某个界面 // 打开设置->通用[[UIApplication sharedApplication] openURL:[NSURL URLWithString:@"prefs:root=General"]];// 以下是设置其他界面prefs:root=General&;path=Aboutprefs:root=General&;path=ACCESSIBILITYprefs:root=AIRPLANE_MODEprefs:root=General&;path=AUTOLOCKprefs:root=General&;path=USAGE/CELLULAR_USAGEprefs:root=Brightnessprefs:root=Bluetoothprefs:root=General&;path=DATE_AND_TIMEprefs:root=FACETIMEprefs:root=Generalprefs:root=General&;path=Keyboardprefs:root=CASTLEprefs:root=CASTLE&;path=STORAGE_AND_BACKUPprefs:root=General&;path=INTERNATIONALprefs:root=LOCATION_SERVICESprefs:root=ACCOUNT_SETTINGSprefs:root=MUSICprefs:root=MUSIC&;path=EQprefs:root=MUSIC&;path=VolumeLimitprefs:root=General&;path=Networkprefs:root=NIKE_PLUS_IPODprefs:root=NOTESprefs:root=NOTIFICATIONS_IDprefs:root=Phoneprefs:root=Photosprefs:root=General&;path=ManagedConfigurationListprefs:root=General&;path=Resetprefs:root=Sounds&;path=Ringtoneprefs:root=Safariprefs:root=General&;path=Assistantprefs:root=Soundsprefs:root=General&;path=SOFTWARE_UPDATE_LINKprefs:root=STOREprefs:root=TWITTERprefs:root=FACEBOOKprefs:root=General&;path=USAGE prefs:root=VIDEOprefs:root=General&;path=Network/VPNprefs:root=Wallpaperprefs:root=WIFIprefs:root=INTERNET_TETHERINGprefs:root=Phone&;path=Blockedprefs:root=DO_NOT_DISTURB 38、在UITextView中显示html文本UITextView *textView = [[UITextView alloc] initWithFrame:CGRectMake(20, 30, 100, 199)]; textView.backgroundColor = [UIColor redColor]; [self.view addSubview:textView]; NSString *htmlString = @"<h1>Header</h1><h2>Subheader</h2>Some <em>text</em>![](http://blogs.babble.com/famecrawler/files/2010/11/mickey_mouse-1097.jpg)"; NSAttributedString *attributedString = [[NSAttributedString alloc] initWithData: [htmlString dataUsingEncoding:NSUnicodeStringEncoding] options: @{ NSDocumentTypeDocumentAttribute: NSHTMLTextDocumentType } documentAttributes: nil error: nil]; textView.attributedText = attributedString; 39、监听scrollView是否滚动到了顶部/底部 -(void)scrollViewDidScroll: (UIScrollView*)scrollView{ float scrollViewHeight = scrollView.frame.size.height; float scrollContentSizeHeight = scrollView.contentSize.height; float scrollOffset = scrollView.contentOffset.y; if (scrollOffset == 0) { // 滚动到了顶部 } else if (scrollOffset + scrollViewHeight == scrollContentSizeHeight) { // 滚动到了底部 }} 40、UISlider增量/减量为固定值(假如为5) - (void)setupSlider{ UISlider *slider = [[UISlider alloc] init]; [self.view addSubview:slider]; [slider addTarget:self action:@selector(sliderAction:) forControlEvents:UIControlEventValueChanged]; slider.maximumValue = 100; slider.minimumValue = 0; slider.frame = CGRectMake(200, 20, 100, 30);}- (void)sliderAction:(UISlider *)slider{ [slider setValue:((int)((slider.value + 2.5) / 5) * 5) animated:NO];} 41、选中textField或者textView所有文本(我这里以textView为例) [self.textView setSelectedTextRange:[self.textView textRangeFromPosition:self.textView.beginningOfDocument toPosition:self.textView.endOfDocument]] 42、从导航控制器中删除某个控制器// 方法一、知道这个控制器所处的导航控制器下标NSMutableArray *navigationArray = [[NSMutableArray alloc] initWithArray: self.navigationController.viewControllers];[navigationArray removeObjectAtIndex: 2]; self.navigationController.viewControllers = navigationArray;// 方法二、知道具体是哪个控制器NSArray* tempVCA = [self.navigationController viewControllers];for(UIViewController *tempVC in tempVCA){ if([tempVC isKindOfClass:[urViewControllerClass class]]) { [tempVC removeFromParentViewController]; }} 43、隐藏UITextView/UITextField光标 textField.tintColor = [UIColor clearColor]; 44、当UITextView/UITextField中没有文字时,禁用回车键textField.enablesReturnKeyAutomatically = YES; 45、字符串encode编码(编码url字符串不成功的问题) // 我们一般用这个方法处理stringByAddingPercentEscapesUsingEncoding但是这个方法好想不会处理/和&;这种特殊符号,这种情况就需要用下边这个方法处理@implementation NSString (NSString_Extended)- (NSString *)urlencode { NSMutableString *output = [NSMutableString string]; const unsigned char *source = (const unsigned char *)[self UTF8String]; int sourceLen = strlen((const char *)source); for (int i = 0; i < sourceLen; ++i) { const unsigned char thisChar = source[i]; if (thisChar == ' '){ [output appendString:@"+"]; } else if (thisChar == '.' || thisChar == '-' || thisChar == '_' || thisChar == '~' || (thisChar >= 'a' &;&; thisChar <= 'z') || (thisChar >= 'A' &;&; thisChar <= 'Z') || (thisChar >= '0' &;&; thisChar <= '9')) { [output appendFormat:@"%c", thisChar]; } else { [output appendFormat:@"%%%02X", thisChar]; } } return output;} 46、计算UILabel上某段文字的frame @implementation UILabel (TextRect)- (CGRect)boundingRectForCharacterRange:(NSRange)range{ NSTextStorage *textStorage = [[NSTextStorage alloc] initWithAttributedString:[self attributedText]]; NSLayoutManager *layoutManager = [[NSLayoutManager alloc] init]; [textStorage addLayoutManager:layoutManager]; NSTextContainer *textContainer = [[NSTextContainer alloc] initWithSize:[self bounds].size]; textContainer.lineFragmentPadding = 0; [layoutManager addTextContainer:textContainer]; NSRange glyphRange; [layoutManager characterRangeForGlyphRange:range actualGlyphRange:&;glyphRange];return [layoutManager boundingRectForGlyphRange:glyphRange inTextContainer:textContainer];} 47、获取随机UUID NSString *result;if([[[UIDevice currentDevice] systemVersion] floatValue] > 6.0) { result = [[NSUUID UUID] UUIDString]; } else { CFUUIDRef uuidRef = CFUUIDCreate(NULL); CFStringRef uuid = CFUUIDCreateString(NULL, uuidRef); CFRelease(uuidRef); result = (__bridge_transfer NSString *)uuid; }48、仿苹果抖动动画 #define RADIANS(degrees) (((degrees) * M_PI) / 180.0)- (void)startAnimate { view.transform = CGAffineTransformRotate(CGAffineTransformIdentity, RADIANS(-5)); [UIView animateWithDuration:0.25 delay:0.0 options:(UIViewAnimationOptionAllowUserInteraction | UIViewAnimationOptionRepeat | UIViewAnimationOptionAutoreverse) animations:^ { view.transform = CGAffineTransformRotate(CGAffineTransformIdentity, RADIANS(5)); } completion:nil];}- (void)stopAnimate { [UIView animateWithDuration:0.25 delay:0.0 options:(UIViewAnimationOptionAllowUserInteraction | UIViewAnimationOptionBeginFromCurrentState | UIViewAnimationOptionCurveLinear) animations:^ { view.transform = CGAffineTransformIdentity; } completion:nil];} 49、修改UISearBar内部背景颜色UITextField *textField = [_searchBar valueForKey:@"_searchField"];textField.backgroundColor = [UIColor redColor];50、UITextView滚动到顶部 // 方法一 [self.textView scrollRangeToVisible:NSMakeRange(0, 0)]; // 方法二 [self.textView setContentOffset:CGPointZero animated:YES]; 51、通知监听APP生命周期

UIApplicationDidEnterBackgroundNotification 应用程序进入后台
UIApplicationWillEnterForegroundNotification 应用程序将要进入前台
UIApplicationDidFinishLaunchingNotification 应用程序完成启动
UIApplicationDidFinishLaunchingNotification 应用程序由挂起变的活跃
UIApplicationWillResignActiveNotification 应用程序挂起(有电话进来或者锁屏)
UIApplicationDidReceiveMemoryWarningNotification 应用程序收到内存警告
UIApplicationDidReceiveMemoryWarningNotification 应用程序终止(后台杀死、手机关机等)
UIApplicationSignificantTimeChangeNotification 当有重大时间改变(凌晨0点,设备时间被修改,时区改变等)
UIApplicationWillChangeStatusBarOrientationNotification 设备方向将要改变
UIApplicationDidChangeStatusBarOrientationNotification 设备方向改变
UIApplicationWillChangeStatusBarFrameNotification 设备状态栏frame将要改变
UIApplicationDidChangeStatusBarFrameNotification 设备状态栏frame改变
UIApplicationBackgroundRefreshStatusDidChangeNotification 应用程序在后台下载内容的状态发生变化
UIApplicationProtectedDataWillBecomeUnavailable 本地受保护的文件被锁定,无法访问
UIApplicationProtectedDataWillBecomeUnavailable 本地受保护的文件可用了

52、触摸事件类型

UIControlEventTouchCancel 取消控件当前触发的事件
UIControlEventTouchDown 点按下去的事件
UIControlEventTouchDownRepeat 重复的触动事件
UIControlEventTouchDragEnter 手指被拖动到控件的边界的事件
UIControlEventTouchDragExit 一个手指从控件内拖到外界的事件
UIControlEventTouchDragInside 手指在控件的边界内拖动的事件
UIControlEventTouchDragOutside 手指在控件边界之外被拖动的事件
UIControlEventTouchUpInside 手指处于控制范围内的触摸事件
UIControlEventTouchUpOutside 手指超出控制范围的控制中的触摸事件

53、UITextField文字周围增加边距 // 子类化UITextField,增加insert属性@interface WZBTextField : UITextField@property (nonatomic, assign) UIEdgeInsets insets;@end// 在.m文件重写下列方法- (CGRect)textRectForBounds:(CGRect)bounds { CGRect paddedRect = UIEdgeInsetsInsetRect(bounds, self.insets); if (self.rightViewMode == UITextFieldViewModeAlways || self.rightViewMode == UITextFieldViewModeUnlessEditing) { return [self adjustRectWithWidthRightView:paddedRect]; } return paddedRect;}- (CGRect)placeholderRectForBounds:(CGRect)bounds { CGRect paddedRect = UIEdgeInsetsInsetRect(bounds, self.insets); if (self.rightViewMode == UITextFieldViewModeAlways || self.rightViewMode == UITextFieldViewModeUnlessEditing) { return [self adjustRectWithWidthRightView:paddedRect]; } return paddedRect;}- (CGRect)editingRectForBounds:(CGRect)bounds { CGRect paddedRect = UIEdgeInsetsInsetRect(bounds, self.insets); if (self.rightViewMode == UITextFieldViewModeAlways || self.rightViewMode == UITextFieldViewModeWhileEditing) { return [self adjustRectWithWidthRightView:paddedRect]; } return paddedRect;}- (CGRect)adjustRectWithWidthRightView:(CGRect)bounds { CGRect paddedRect = bounds; paddedRect.size.width -= CGRectGetWidth(self.rightView.frame); return paddedRect;} 54、监听UISlider拖动状态 // 添加事件[slider addTarget:self action:@selector(sliderValurChanged:forEvent:) forControlEvents:UIControlEventValueChanged];// 实现方法- (void)sliderValurChanged:(UISlider*)slider forEvent:(UIEvent*)event { UITouch *touchEvent = [[event allTouches] anyObject]; switch (touchEvent.phase) {case UITouchPhaseBegan: NSLog(@"开始拖动"); break; case UITouchPhaseMoved: NSLog(@"正在拖动"); break; case UITouchPhaseEnded:NSLog(@"结束拖动"); break; default: break; }} 55、设置UITextField光标位置 // textField需要设置的textField,index要设置的光标位置- (void)cursorLocation:(UITextField *)textField index:(NSInteger)index{ NSRange range = NSMakeRange(index, 0); UITextPosition *start = [textField positionFromPosition:[textField beginningOfDocument] offset:range.location]; UITextPosition *end = [textField positionFromPosition:start offset:range.length]; [textField setSelectedTextRange:[textField textRangeFromPosition:start toPosition:end]];} 56、去除webView底部黑色[webView setBackgroundColor:[UIColor clearColor]]; [webView setOpaque:NO]; for (UIView *v1 in [webView subviews]) { if ([v1 isKindOfClass:[UIScrollView class]]) { for (UIView *v2 in v1.subviews) { if ([v2 isKindOfClass:[UIImageView class]]) { v2.hidden = YES; } } } } 57、获取collectionViewCell在屏幕中的frame UICollectionViewLayoutAttributes *attributes = [collectionView layoutAttributesForItemAtIndexPath:indexPath];CGRect cellRect = attributes.frame;CGRect cellFrameInSuperview = [collectionView convertRect:cellRect toView:[cv superview]]; 58、比较两个UIImage是否相等 - (BOOL)image:(UIImage *)image1 isEqualTo:(UIImage *)image2{ NSData *data1 = UIImagePNGRepresentation(image1); NSData *data2 = UIImagePNGRepresentation(image2); return [data1 isEqual:data2];} 59、解决当UIScrollView上有UIButton的时候,触摸到button滑动不了的问题 // 子类化UIScrollView,并重写以下方法- (instancetype)initWithFrame:(CGRect)frame { if (self = [super initWithFrame:frame]) { self.delaysContentTouches = NO; }return self;}- (BOOL)touchesShouldCancelInContentView:(UIView *)view { if ([view isKindOfClass:UIButton.class]) { return YES; } return [super touchesShouldCancelInContentView:view];} 60、UITextView中的文字添加阴影效果 - (void)setTextLayer:(UITextView *)textView color:(UIColor *)color{ CALayer *textLayer = ((CALayer *)[textView.layer.sublayers objectAtIndex:0]); textLayer.shadowColor = color.CGColor; textLayer.shadowOffset = CGSizeMake(0.0f, 1.0f); textLayer.shadowOpacity = 1.0f; textLayer.shadowRadius = 1.0f;} 61、MD5加密 + (NSString *)md5:(NSString *)str{ const char *concat_str = [str UTF8String]; unsigned char result[CC_MD5_DIGEST_LENGTH]; CC_MD5(concat_str, (unsigned int)strlen(concat_str), result); NSMutableString *hash = [NSMutableString string]; for (int i =0; i <16; i++){ [hash appendFormat:@"%02X", result[i]]; }return [hash uppercaseString];} 62、base64加密 @interface NSData (Base64)/** * @brief 字符串base64后转data */+ (NSData *)dataWithBase64EncodedString:(NSString *)string{ if (![string length]) return nil; NSData *decoded = nil;#if __MAC_OS_X_VERSION_MIN_REQUIRED < __MAC_10_9 || __IPHONE_OS_VERSION_MIN_REQUIRED < __IPHONE_7_0 if (![NSData instancesRespondToSelector:@selector(initWithBase64EncodedString:options:)]) {#pragma clang diagnostic push#pragma clang diagnostic ignored "-Wdeprecated-declarations" decoded = [[self alloc] initWithBase64Encoding:[string stringByReplacingOccurrencesOfString:@"[^A-Za-z0-9+/=]" withString:@"" options:NSRegularExpressionSearch range:NSMakeRange(0, [string length])]];#pragma clang diagnostic pop } else#endif { decoded = [[self alloc] initWithBase64EncodedString:string options:NSDataBase64DecodingIgnoreUnknownCharacters]; } return [decoded length]? decoded: nil;}/** * @brief NSData转string * @param wrapWidth 换行长度 76 64 */- (NSString *)base64EncodedStringWithWrapWidth:(NSUInteger)wrapWidth{ if (![self length]) return nil; NSString *encoded = nil;#if __MAC_OS_X_VERSION_MIN_REQUIRED < __MAC_10_9 || __IPHONE_OS_VERSION_MIN_REQUIRED < __IPHONE_7_0 if (![NSData instancesRespondToSelector:@selector(base64EncodedStringWithOptions:)]) {#pragma clang diagnostic push#pragma clang diagnostic ignored "-Wdeprecated-declarations" encoded = [self base64Encoding];#pragma clang diagnostic pop } else#endif { switch (wrapWidth) { case 64: { return [self base64EncodedStringWithOptions:NSDataBase64Encoding64CharacterLineLength]; } case 76: { return [self base64EncodedStringWithOptions:NSDataBase64Encoding76CharacterLineLength]; } default: { encoded = [self base64EncodedStringWithOptions:(NSDataBase64EncodingOptions)0]; } } } if (!wrapWidth || wrapWidth >= [encoded length]) { return encoded; } wrapWidth = (wrapWidth / 4) * 4; NSMutableString *result = [NSMutableString string]; for (NSUInteger i = 0; i < [encoded length]; i+= wrapWidth) { if (i + wrapWidth >= [encoded length]) { [result appendString:[encoded substringFromIndex:i]]; break; } [result appendString:[encoded substringWithRange:NSMakeRange(i, wrapWidth)]]; [result appendString:@"/r/n"]; } return result;}/** * @brief NSData转string 换行长度默认64 */- (NSString *)base64EncodedString{ return [self base64EncodedStringWithWrapWidth:0];} 63、AES加密 #import <CommonCrypto/CommonCryptor.h>@interface NSData (AES)/** * 利用AES加密数据 */- (NSData*)encryptedWithAESUsingKey:(NSString*)key andIV:(NSData*)iv { NSData *keyData = [key dataUsingEncoding:NSUTF8StringEncoding]; size_t dataMoved;NSMutableData *encryptedData = [NSMutableData dataWithLength:self.length + kCCBlockSizeAES128]; CCCryptorStatus status = CCCrypt(kCCEncrypt,kCCAlgorithmAES128,kCCOptionPKCS7Padding,keyData.bytes,keyData.length,iv.bytes,self.bytes,self.length,encryptedData.mutableBytes, encryptedData.length,&;dataMoved); if (status == kCCSuccess) { encryptedData.length = dataMoved; return encryptedData; } return nil;}/** * @brief 利用AES解密据 */- (NSData*)decryptedWithAESUsingKey:(NSString*)key andIV:(NSData*)iv { NSData *keyData = [key dataUsingEncoding:NSUTF8StringEncoding]; size_t dataMoved;NSMutableData *decryptedData = [NSMutableData dataWithLength:self.length + kCCBlockSizeAES128]; CCCryptorStatus result = CCCrypt(kCCDecrypt,kCCAlgorithmAES128,kCCOptionPKCS7Padding,keyData.bytes,keyData.length,iv.bytes,self.bytes,self.length,decryptedData.mutableBytes, decryptedData.length,&;dataMoved); if (result == kCCSuccess) { decryptedData.length = dataMoved; return decryptedData; } return nil;} 64、3DES加密 #import <CommonCrypto/CommonCryptor.h>@interface NSData (3DES)/** * 利用3DES加密数据 */- (NSData*)encryptedWith3DESUsingKey:(NSString*)key andIV:(NSData*)iv { NSData *keyData = [key dataUsingEncoding:NSUTF8StringEncoding]; size_t dataMoved;NSMutableData *encryptedData = [NSMutableData dataWithLength:self.length + kCCBlockSize3DES]; CCCryptorStatus result = CCCrypt(kCCEncrypt,kCCAlgorithm3DES,kCCOptionPKCS7Padding,keyData.bytes,keyData.length,iv.bytes,self.bytes,self.length,encryptedData.mutableBytes,encryptedData.length,&;dataMoved); if (result == kCCSuccess) { encryptedData.length = dataMoved; return encryptedData; } return nil;}/** * @brief 利用3DES解密数据 */- (NSData*)decryptedWith3DESUsingKey:(NSString*)key andIV:(NSData*)iv { NSData *keyData = [key dataUsingEncoding:NSUTF8StringEncoding]; size_t dataMoved;NSMutableData *decryptedData = [NSMutableData dataWithLength:self.length + kCCBlockSize3DES]; CCCryptorStatus result = CCCrypt(kCCDecrypt,kCCAlgorithm3DES,kCCOptionPKCS7Padding,keyData.bytes,keyData.length,iv.bytes,self.bytes,self.length,decryptedData.mutableBytes,decryptedData.length,&;dataMoved); if (result == kCCSuccess) { decryptedData.length = dataMoved; return decryptedData; } return nil;} 65、单个页面多个网络请求的情况,需要监听所有网络请求结束后刷新UIdispatch_group_t group = dispatch_group_create(); dispatch_queue_t serialQueue = dispatch_queue_create("com.wzb.test.www", DISPATCH_QUEUE_SERIAL); dispatch_group_enter(group); dispatch_group_async(group, serialQueue, ^{ // 网络请求一 [WebClick getDataSuccess:^(ResponseModel *model) { dispatch_group_leave(group); } failure:^(NSString *err) { dispatch_group_leave(group); }]; }); dispatch_group_enter(group); dispatch_group_async(group, serialQueue, ^{ // 网络请求二 [WebClick getDataSuccess:getBigTypeRM onSuccess:^(ResponseModel *model) { dispatch_group_leave(group); } failure:^(NSString *errorString) { dispatch_group_leave(group); }]; }); dispatch_group_enter(group); dispatch_group_async(group, serialQueue, ^{ // 网络请求三 [WebClick getDataSuccess:^{ dispatch_group_leave(group); } failure:^(NSString *errorString) { dispatch_group_leave(group); }]; }); // 所有网络请求结束后会来到这个方法 dispatch_group_notify(group, serialQueue, ^{ dispatch_async(dispatch_get_global_queue(0, 0), ^{ dispatch_async(dispatch_get_main_queue(), ^{ // 刷新UI }); }); }); 66、解决openUrl延时问题 // 方法一dispatch_async(dispatch_get_main_queue(), ^{ UIApplication *application = [UIApplication sharedApplication]; if ([application respondsToSelector:@selector(openURL:options:completionHandler:)]) { [application openURL:URL options:@{} completionHandler:nil]; } else { [application openURL:URL]; } });// 方法二[self performSelector:@selector(redirectToURL:) withObject:url afterDelay:0.1];- (void) redirectToURL{UIApplication *application = [UIApplication sharedApplication]; if ([application respondsToSelector:@selector(openURL:options:completionHandler:)]) { [application openURL:URL options:@{} completionHandler:nil]; } else { [application openURL:URL]; }} 67、页面跳转实现翻转动画 // modal方式 TestViewController *vc = [[TestViewController alloc] init]; vc.view.backgroundColor = [UIColor redColor]; vc.modalTransitionStyle = UIModalTransitionStyleCoverVertical; [self presentViewController:vc animated:YES completion:nil];// push方式 TestViewController *vc = [[TestViewController alloc] init]; vc.view.backgroundColor = [UIColor redColor]; [UIView beginAnimations:@"View Flip" context:nil]; [UIView setAnimationDuration:0.80]; [UIView setAnimationCurve:UIViewAnimationCurveEaseInOut]; [UIView setAnimationTransition:UIViewAnimationTransitionFlipFromRight forView:self.navigationController.view cache:NO]; [self.navigationController pushViewController:vc animated:YES]; [UIView commitAnimations]; 68、tableView实现无限滚动 - (void)scrollViewDidScroll:(UIScrollView *)scrollView{CGFloat actualPosition = scrollView.contentOffset.y; CGFloat contentHeight = scrollView.contentSize.height - scrollView.frame.size.height; if (actualPosition >= contentHeight) { [self.dataArr addObjectsFromArray:self.dataArr]; [self.tableView reloadData]; }} 69、代码方式调整屏幕亮度 // brightness属性值在0-1之间,0代表最小亮度,1代表最大亮度[[UIScreen mainScreen] setBrightness:0.5]; 70、获取当前应用CUP用量 float cpu_usage(){kern_return_t kr; task_info_data_t tinfo; mach_msg_type_number_t task_info_count; task_info_count = TASK_INFO_MAX; kr = task_info(mach_task_self(), TASK_BASIC_INFO, (task_info_t)tinfo, &;task_info_count); if (kr != KERN_SUCCESS) { return -1; } task_basic_info_t basic_info; thread_array_t thread_list; mach_msg_type_number_t thread_count; thread_info_data_t thinfo; mach_msg_type_number_t thread_info_count; thread_basic_info_t basic_info_th; uint32_t stat_thread = 0; // Mach threads basic_info = (task_basic_info_t)tinfo; // get threads in the task kr = task_threads(mach_task_self(), &;thread_list, &;thread_count); if (kr != KERN_SUCCESS) { return -1; } if (thread_count > 0) stat_thread += thread_count; long tot_sec = 0; long tot_usec = 0; float tot_cpu = 0; int j; for (j = 0; j < (int)thread_count; j++) { thread_info_count = THREAD_INFO_MAX; kr = thread_info(thread_list[j], THREAD_BASIC_INFO, (thread_info_t)thinfo, &;thread_info_count); if (kr != KERN_SUCCESS) { return -1; } basic_info_th = (thread_basic_info_t)thinfo; if (!(basic_info_th->flags &; TH_FLAGS_IDLE)) { tot_sec = tot_sec + basic_info_th->user_time.seconds + basic_info_th->system_time.seconds; tot_usec = tot_usec + basic_info_th->user_time.microseconds + basic_info_th->system_time.microseconds; tot_cpu = tot_cpu + basic_info_th->cpu_usage / (float)TH_USAGE_SCALE * 100.0; } } // for each thread kr = vm_deallocate(mach_task_self(), (vm_offset_t)thread_list, thread_count * sizeof(thread_t)); assert(kr == KERN_SUCCESS); return tot_cpu;} 71、float数据取整四舍五入 CGFloat f = 4.65; NSLog(@"%d", (int)f); // 打印结果4 CGFloat f = 4.65; NSLog(@"%d", (int)round(f)); // 打印结果5 72、删除UISearchBar系统默认边框 // 方法一 searchBar.searchBarStyle = UISearchBarStyleMinimal; // 方法二 [searchBar setBackgroundImage:[[UIImage alloc]init]]; // 方法三 searchBar.barTintColor = [UIColor whiteColor]; 73、为UICollectionViewCell设置圆角和阴影cell.contentView.layer.cornerRadius = 2.0f;cell.contentView.layer.borderWidth = 1.0f;cell.contentView.layer.borderColor = [UIColor clearColor].CGColor;cell.contentView.layer.masksToBounds = YES;cell.layer.shadowColor = [UIColor lightGrayColor].CGColor;cell.layer.shadowOffset = CGSizeMake(0, 2.0f);cell.layer.shadowRadius = 2.0f;cell.layer.shadowOpacity = 1.0f;cell.layer.masksToBounds = NO;cell.layer.shadowPath = [UIBezierPath bezierPathWithRoundedRect:cell.bounds cornerRadius:cell.contentView.layer.cornerRadius].CGPath; 74、让正在滑动的scrollView停止滚动(不是禁止,而是暂时停止滚动) [scrollView setContentOffset:scrollView.contentOffset animated:NO]; 75、使用xib设置UIView的边框、圆角

圆角和边框看下图即可设置

iOS 开发经验 - 转载_IOS
xib设置圆角边框.png

但是增加layer.borderColor的keyPath设置边框颜色并不能起作用,后来查了资料,这里应该用layer.borderUIColor,但是这里设置的颜色不起作用,无论设置什么颜色显示出来的都是黑色的。后来又去查了下,有种解决方案是给CALayer添加一个分类,提供一个 - (void)setBorderUIColor:(UIColor *)color;方法就可以解决了,实现如下:

iOS 开发经验 - 转载_IOS
xib设置边框颜色.png #import "CALayer+BorderColor.h"@implementation CALayer (BorderColor)- (void)setBorderUIColor:(UIColor *)color{self.borderColor = color.CGColor;} 76、根据经纬度获取城市等信息 // 创建经纬度 CLLocation *location = [[CLLocation alloc] initWithLatitude:latitude longitude:longitude]; //创建一个译码器 CLGeocoder *cLGeocoder = [[CLGeocoder alloc] init]; [cLGeocoder reverseGeocodeLocation:userLocation completionHandler:^(NSArray *placemarks, NSError *error) { CLPlacemark *place = [placemarks objectAtIndex:0]; // 位置名NSLog(@"name,%@",place.name); // 街道NSLog(@"thoroughfare,%@",place.thoroughfare); // 子街道NSLog(@"subThoroughfare,%@",place.subThoroughfare); // 市NSLog(@"locality,%@",place.locality); // 区NSLog(@"subLocality,%@",place.subLocality); // 国家NSLog(@"country,%@",place.country); } }];/* CLPlacemark中属性含义name 地名thoroughfare 街道subThoroughfare 街道相关信息,例如门牌等locality 城市subLocality 城市相关信息,例如标志性建筑administrativeArea 直辖市subAdministrativeArea 其他行政区域信息(自治区等)postalCode 邮编ISOcountryCode 国家编码country 国家inlandWater 水源,湖泊ocean 海洋areasOfInterest 关联的或利益相关的地标*/ 77、如何防止添加多个NSNotification观察者? // 解决方案就是添加观察者之前先移除下这个观察者[[NSNotificationCenter defaultCenter] removeObserver:observer name:name object:object]; [[NSNotificationCenter defaultCenter] addObserver:observer selector:selector name:name object:object]; 78、将一个xib添加到另外一个xib上 // 假设你的自定义view名字为CustomView,你需要在CustomView.m中重写 `- (instancetype)initWithCoder:(NSCoder *)aDecoder` 方法,代码如下:- (instancetype)initWithCoder:(NSCoder *)aDecoder { if ((self = [super initWithCoder:aDecoder])) { [self addSubview:[[[NSBundle mainBundle] loadNibNamed:@"CustomView" owner:self options:nil] objectAtIndex:0]]; }return self;} iOS 开发经验 - 转载_IOS
将一个xib添加到另外一个xib上.png 79、处理字符串,使其首字母大写 NSString *str = @"abcdefghijklmn"; NSString *resultStr; if (str &;&; str.length > 0) { resultStr = [str stringByReplacingCharactersInRange:NSMakeRange(0,1) withString:[[str substringToIndex:1] capitalizedString]]; } NSLog(@"%@", resultStr); 80、判断一个UIAlertView/UIAlertController是否显示 // UIAlertView自带属性if (alert.visible){ NSLog(@"显示了");} else { NSLog(@"未显示");}// UIAlertController没有visible属性,需要自己判断,添加一个全局变量 BOOL visibleUIAlertController *alertController = [UIAlertController alertControllerWithTitle:@"Title" message:@"message" preferredStyle:UIAlertControllerStyleAlert]; UIAlertAction *alertAction = [UIAlertAction actionWithTitle:@"ActionTitle" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) { self.visible = NO; }]; UIAlertAction *calcelAction = [UIAlertAction actionWithTitle:@"calcelTitle" style:UIAlertActionStyleCancel handler:^(UIAlertAction * _Nonnull action) {self.visible = NO; }]; [alertController addAction:alertAction]; [alertController addAction:calcelAction]; [self presentViewController:alertController animated:YES completion:^{ self.visible = YES; }]; 81、获取字符串中的数字 - (NSString *)getNumberFromStr:(NSString *)str{ NSCharacterSet *nonDigitCharacterSet = [[NSCharacterSet decimalDigitCharacterSet] invertedSet]; return [[str componentsSeparatedByCharactersInSet:nonDigitCharacterSet] componentsJoinedByString:@""];} NSLog(@"%@", [self getNumberFromStr:@"a0b0c1d2e3f4fda8fa8fad9fsad23"]); // 0012348892382、为UIView的某个方向添加边框 // 添加UIView分类// UIView+WZB.h#import <UIKit/UIKit.h>/** 边框方向 - WZBBorderDirectionTop: 顶部 - WZBBorderDirectionLeft: 左边 - WZBBorderDirectionBottom: 底部 - WZBBorderDirectionRight: 右边 */typedef NS_ENUM(NSInteger, WZBBorderDirectionType) { WZBBorderDirectionTop = 0, WZBBorderDirectionLeft, WZBBorderDirectionBottom, WZBBorderDirectionRight};@interface UIView (WZB)/** 为UIView的某个方向添加边框 @param direction 边框方向 @param color 边框颜色 @param width 边框宽度 */- (void)wzb_addBorder:(WZBBorderDirectionType)direction color:(UIColor *)color width:(CGFloat)width;@end// UIView+WZB.m#import "UIView+WZB.h"@implementation UIView (WZB)- (void)wzb_addBorder:(WZBBorderDirectionType)direction color:(UIColor *)color width:(CGFloat)width{ CALayer *border = [CALayer layer]; border.backgroundColor = color.CGColor; switch (direction) { case WZBBorderDirectionTop: { border.frame = CGRectMake(0.0f, 0.0f, self.bounds.size.width, width); } break;case WZBBorderDirectionLeft: { border.frame = CGRectMake(0.0f, 0.0f, width, self.bounds.size.height); } break; case WZBBorderDirectionBottom: { border.frame = CGRectMake(0.0f, self.bounds.size.height - width, self.bounds.size.width, width); } break; case WZBBorderDirectionRight: { border.frame = CGRectMake(self.bounds.size.width - width, 0, width, self.bounds.size.height); } break; default: break; } [self.layer addSublayer:border];} 83、通过属性设置UISwitch、UIProgressView等控件的宽高 mySwitch.transform = CGAffineTransformMakeScale(5.0f, 5.0f);progressView.transform = CGAffineTransformMakeScale(5.0f, 5.0f);84、自动搜索功能,用户连续输入的时候不搜索,用户停止输入的时候自动搜索(我这里设置的是0.5s,可根据需求更改) // 输入框文字改变的时候调用-(void)searchBar:(UISearchBar *)searchBar textDidChange:(NSString *)searchText{ // 先取消调用搜索方法 [NSObject cancelPreviousPerformRequestsWithTarget:self selector:@selector(searchNewResult) object:nil]; // 0.5秒后调用搜索方法 [self performSelector:@selector(searchNewResult) withObject:nil afterDelay:0.5];}85、修改UISearchBar的占位文字颜色 // 方法一(推荐使用) UITextField *searchField = [searchBar valueForKey:@"_searchField"]; [searchField setValue:[UIColor blueColor] forKeyPath:@"_placeholderLabel.textColor"]; // 方法二(已过期) [[UILabel appearanceWhenContainedIn:[UISearchBar class], nil] setTextColor:[UIColor redColor]]; // 方法三(已过期) NSDictionary *placeholderAttributes = @{NSForegroundColorAttributeName : [UIColor redColor], NSFontAttributeName : [UIFont fontWithName:@"HelveticaNeue" size:15],}; NSAttributedString *attributedPlaceholder = [[NSAttributedString alloc] initWithString:searchBar.placeholder attributes:placeholderAttributes]; [[UITextField appearanceWhenContainedIn:[UISearchBar class], nil] setAttributedPlaceholder:attributedPlaceholder]; 86、某个界面多个事件同时响应引起的问题(比如,两个button同时按push到新界面,两个都会响应,可能导致push重叠) // UIView有个属性叫做exclusiveTouch,设置为YES后,其响应事件会和其他view互斥(有其他view事件响应的时候点击它不起作用)view.exclusiveTouch = YES;// 一个一个设置太麻烦了,可以全局设置[[UIView appearance] setExclusiveTouch:YES];// 或者只设置button[[UIButton appearance] setExclusiveTouch:YES]; 87、修改tabBar的frame // 子类化UITabBarViewController,我这里以修改tabBar高度为例,重写viewWillLayoutSubviews方法#import "WZBTabBarViewController.h"@interface WZBTabBarViewController ()@end@implementation WZBTabBarViewController- (void)viewWillLayoutSubviews { CGRect tabFrame = self.tabBar.frame; tabFrame.size.height = 100; tabFrame.origin.y = self.view.frame.size.height - 100; self.tabBar.frame = tabFrame;}@end 88、修改键盘背景颜色 // 设置某个键盘颜色 textField.keyboardAppearance = UIKeyboardAppearanceAlert;// 设置工程中所有键盘颜色[[UITextField appearance] setKeyboardAppearance:UIKeyboardAppearanceAlert]; 89、修改image颜色 UIImage *image = [UIImage imageNamed:@"test"]; imageView.image = [image imageWithRenderingMode:UIImageRenderingModeAlwaysTemplate]; CGRect rect = CGRectMake(0, 0, image.size.width, image.size.height);UIGraphicsBeginImageContext(rect.size); CGContextRef context = UIGraphicsGetCurrentContext(); CGContextClipToMask(context, rect, image.CGImage); CGContextSetFillColorWithColor(context, [[UIColor redColor] CGColor]); CGContextFillRect(context, rect); UIImage *img = UIGraphicsGetImageFromCurrentImageContext();UIGraphicsEndImageContext(); UIImage *flippedImage = [UIImage imageWithCGImage:img.CGImage scale:1.0 orientation: UIImageOrientationDownMirrored]; imageView.image = flippedImage; 90、动画执行removeFromSuperview [UIView animateWithDuration:0.2 animations:^{ view.alpha = 0.0f; } completion:^(BOOL finished){ [view removeFromSuperview]; }]; 91、启动页显示延时 - (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions{// 延时10s sleep(10); return YES;} 92、设置UIButton高亮时的背景颜色 // 方法一、子类化UIButton,重写setHighlighted:方法,代码如下#import "WZBButton.h"@implementation WZBButton- (void)setHighlighted:(BOOL)highlighted { [super setHighlighted:highlighted]; UIColor *normalColor = [UIColor greenColor]; UIColor *highlightedColor = [UIColor redColor];self.backgroundColor = highlighted ? highlightedColor : normalColor;}// 方法二、利用setBackgroundImage:forState:方法[button setBackgroundImage:[self imageWithColor:[UIColor blueColor]] forState:UIControlStateHighlighted];- (UIImage *)imageWithColor:(UIColor *)color { CGRect rect = CGRectMake(0.0f, 0.0f, 1.0f, 1.0f); UIGraphicsBeginImageContext(rect.size);CGContextRef context = UIGraphicsGetCurrentContext();CGContextSetFillColorWithColor(context, [color CGColor]);CGContextFillRect(context, rect); UIImage *image = UIGraphicsGetImageFromCurrentImageContext();UIGraphicsEndImageContext(); return image;} 93、关于图片拉伸

推荐看这个博客,讲的很详细http://blog.csdn.net/q199109106q/article/details/8615661

94、利用runtime获取一个类所有属性 - (NSArray *)allPropertyNames:(Class)aClass{ unsigned count; objc_property_t *properties = class_copyPropertyList(aClass, &;count); NSMutableArray *rv = [NSMutableArray array]; unsigned i; for (i = 0; i < count; i++) { objc_property_t property = properties[i]; NSString *name = [NSString stringWithUTF8String:property_getName(property)]; [rv addObject:name]; } free(properties); return rv;} 95、设置textView的某段文字变成其他颜色 - (void)setupTextView:(UITextView *)textView text:(NSString *)text color:(UIColor *)color { NSMutableAttributedString *string = [[NSMutableAttributedString alloc]initWithString:textView.text]; [string addAttribute:NSForegroundColorAttributeName value:color range:[textView.text rangeOfString:text]]; [textView setAttributedText:string];} 96、让push跳转动画像modal跳转动画那样效果(从下往上推上来) - (void)push{TestViewController *vc = [[TestViewController alloc] init]; vc.view.backgroundColor = [UIColor redColor]; CATransition* transition = [CATransition animation]; transition.duration = 0.4f; transition.type = kCATransitionMoveIn; transition.subtype = kCATransitionFromTop; [self.navigationController.view.layer addAnimation:transition forKey:kCATransition]; [self.navigationController pushViewController:vc animated:NO];}- (void)pop{CATransition* transition = [CATransition animation]; transition.duration = 0.4f; transition.type = kCATransitionReveal; transition.subtype = kCATransitionFromBottom; [self.navigationController.view.layer addAnimation:transition forKey:kCATransition]; [self.navigationController popViewControllerAnimated:NO];} 97、上传图片太大,压缩图片 -(UIImage *)resizeImage:(UIImage *)image{ float actualHeight = image.size.height; float actualWidth = image.size.width; float maxHeight = 300.0; float maxWidth = 400.0; float imgRatio = actualWidth/actualHeight; float maxRatio = maxWidth/maxHeight; float compressionQuality = 0.5;//50 percent compression if (actualHeight > maxHeight || actualWidth > maxWidth) {if(imgRatio < maxRatio) { //adjust width according to maxHeight imgRatio = maxHeight / actualHeight; actualWidth = imgRatio * actualWidth; actualHeight = maxHeight; } else if(imgRatio > maxRatio) { //adjust height according to maxWidth imgRatio = maxWidth / actualWidth; actualHeight = imgRatio * actualHeight; actualWidth = maxWidth; } else { actualHeight = maxHeight; actualWidth = maxWidth; } } CGRect rect = CGRectMake(0.0, 0.0, actualWidth, actualHeight); UIGraphicsBeginImageContext(rect.size); [image drawInRect:rect]; UIImage *img = UIGraphicsGetImageFromCurrentImageContext(); NSData *imageData = UIImageJPEGRepresentation(img, compressionQuality); UIGraphicsEndImageContext(); return [UIImage imageWithData:imageData];}转载自 - http://www.jianshu.com/u/6d5126f52682 以上是iOS 开发经验 - 转载的内容，更多转载经验开发 iOS 的内容，请您使用搜索功能获取相关信息。

iOS 开发经验 - 转载

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