iOS13的modalPresentationStyle默认为UIModalPresentationAutomatic,要想修改,需要手动设置vc.modalPresentationStyle = UIModalPresentationFullScreen;
但是这个修改需要在每个presentViewController:animated:completion:之前加上这样一句代码,需要改动多个文件,多处代码,以后再有页面跳转还需要再加这么一句,太繁琐,容易遗漏。
我们用以下方法就没有那么麻烦了,不需要改变原代码,再有页面跳转,也不用多加代码:
我们为UIViewController建立一个分类,在该分类的.m中加上如下代码
+ (void)load {
// 方法交换,为的是当系统调用viewDidLoad时候,调用的是我们的my_viewDidLoad方法
static dispatch_once_t onceToken;
dispatch_once(&onceToken, ^{
Class class = [self class];
SEL originalSelector = @selector(viewDidLoad);
SEL swizzledSelector = @selector(my_viewDidLoad);
Method originalMethod = class_getInstanceMethod(class, originalSelector);
Method swizzledMethod = class_getInstanceMethod(class, swizzledSelector);
BOOL success = class_addMethod(class, originalSelector, method_getImplementation(swizzledMethod), method_getTypeEncoding(swizzledMethod));
if (success) {
class_replaceMethod(class, swizzledSelector, method_getImplementation(originalMethod), method_getTypeEncoding(originalMethod));
} else {
method_exchangeImplementations(originalMethod, swizzledMethod);
}
});
}
- (void)my_viewDidLoad {
[self my_viewDidLoad]; // 由于方法交换,实际上调用的是系统的viewDidLoad
NSArray *viewcontrollers=self.navigationController.viewControllers;
if (viewcontrollers.count > 1) {
} else {
//present方式
self.modalPresentationStyle = UIModalPresentationFullScreen; // 修改默认值
}
}
使用方法:
UIViewController *vc = [[UIViewController alloc] init];
[self presentViewController:vc animated:YES completion:nil]; // 即使是在iOS13下vc也是全屏显示
修改modalPresentationStyle的值
UIViewController *vc = [[UIViewController alloc] init];
vc.modalPresentationStyle = UIModalPresentationPopover;
[self presentViewController:vc animated:YES completion:nil]; // 不管是在iOS13还是之前版本,都是以UIModalPresentationPopover模式