iOS13的modalPresentationStyle默認爲UIModalPresentationAutomatic,要想修改,需要手動設置vc.modalPresentationStyle = UIModalPresentationFullScreen;
但是這個修改需要在每個presentViewController:animated:completion:之前加上這樣一句代碼,需要改動多個文件,多處代碼,以後再有頁面跳轉還需要再加這麼一句,太繁瑣,容易遺漏。
我們用以下方法就沒有那麼麻煩了,不需要改變原代碼,再有頁面跳轉,也不用多加代碼:
我們爲UIViewController建立一個分類,在該分類的.m中加上如下代碼
+ (void)load {
// 方法交換,爲的是當系統調用viewDidLoad時候,調用的是我們的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]; // 由於方法交換,實際上調用的是系統的viewDidLoad
NSArray *viewcontrollers=self.navigationController.viewControllers;
if (viewcontrollers.count > 1) {
} else {
//present方式
self.modalPresentationStyle = UIModalPresentationFullScreen; // 修改默認值
}
}
使用方法:
UIViewController *vc = [[UIViewController alloc] init];
[self presentViewController:vc animated:YES completion:nil]; // 即使是在iOS13下vc也是全屏顯示
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還是之前版本,都是以UIModalPresentationPopover模式