主要涉及的功能点有:
1、密码输入框要隐藏输入字符,以黑点代替
2、Login时会检查输入框,若输入不合法,弹窗提示用户
3、Reset会清空输入
4、点击界面空白地方的时候,能够收起输入键盘,防止挡住用户点击登陆。
实现代码:
1、对于要隐藏输入的文本框,我们只需要把其secureTextEntry的属性设置为TRUE就行了:
self.password.secureTextEntry=TRUE;
2、Login功能会把用户输入保存到AppDelegate中,这样以后程序中需要的时候还可以取到:
-(IBAction)login:(id)sender{ NSString *userName = [self.userName.text stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceCharacterSet]]; NSString *password = [self.password.text stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceCharacterSet]]; AppDelegate *delegate = (AppDelegate *)[[UIApplication sharedApplication] delegate]; if(userName.length==0||password.length==0){ UIAlertView *alert= [[UIAlertView alloc] initWithTitle:@"Input invalid" message:@"UserName or Password is empty" delegate:nil cancelButtonTitle:@"OK" otherButtonTitles:nil, nil]; [alert show]; [alert release]; return; } [delegate.userState setObject:userName forKey:@"KUserName"]; [delegate.userState setObject:password forKey:@"KPassword"]; AppDelegate *appDelegate = [[UIApplication sharedApplication] delegate]; appDelegate.window.rootViewController = appDelegate.tabBar; }
3、在Reset时,除了清空UI控件中的内容,还需要清空AppDelegate中的内容:
-(IBAction)reset:(id)sender{ self.userName.text=@""; self.password.text=@""; AppDelegate *delegate = (AppDelegate *)[[UIApplication sharedApplication] delegate]; [delegate.userState setObject:@"" forKey:@"KUserName"]; [delegate.userState setObject:@"" forKey:@"KPassword"]; }
注:所有与UI空间绑定的方法都需要返回类型IBAction
4、实现隐藏键盘的原理就是通过调用输入框控件的resignFirstResponder,意思是放弃自己的第一响应者的身份,这样,键盘就会自动消失了。实现的时候,我们需要为界面绑定方法,在界面有touchDown事件发生的时候,调用backgroundTap方法:
-(IBAction)backgroundTap:(id)sender { NSLog(@"%@",@"touch screen"); [self.userName resignFirstResponder]; [self.password resignFirstResponder]; }