摘要: 關(guān)于形如 Presenting view controllers on detached view controllers is discouraged 的處理

使用模態(tài)跳轉(zhuǎn)時(shí)，Xcode有時(shí)候會(huì)出現(xiàn)如下警告

Presenting view controllers on detached view controllersisdiscouraged <>

這樣的警告代碼，如果你認(rèn)為你的層次之間沒(méi)有問(wèn)題（其實(shí)就是層次問(wèn)題。present出來(lái)的模態(tài)窗口，禁止再使用present 來(lái)彈出其它的子窗口）只要把self直接模態(tài)跳轉(zhuǎn)頁(yè)面改成從根控制器跳轉(zhuǎn)即可

解決方法：

把

ViewController *viewController = [[ViewController alloc] init];[selfpresentViewController:viewController animated:YEScompletion:nil];

改成

AppDelegate *delegate = (AppDelegate *)[UIApplicationsharedApplication].delegate;ViewController *viewController = [[ViewController alloc] init];[delegate.window.rootViewController presentViewController:viewController animated:YEScompletion:nil];

即可

方法一：就是通過(guò)上面的方法，先找到appdelegate然后獲取window屬性

KLViewController *rootVc = (KLViewController *)[(AppDelegate *)[UIApplication sharedApplication].delegatewindow].rootViewController;

這種方法除了找根控制器還能找appdelegate類里的定義的任何屬性，如：

- (void) openOrcloseTheList {? ? ? ? AppDelegate *tempAppDelegate = (AppDelegate *)[[UIApplicationsharedApplication] delegate];if(tempAppDelegate.theListVC.closed) {? ? ? ? [tempAppDelegate.theListVC openListView];? ? }else{? ? ? ? [tempAppDelegate.theListVC closeListView];? ? }}

方法二：直接通過(guò)keyWindow來(lái)找根控制器，更直接

KLViewController *rootVc = (KLViewController *)[UIApplicationsharedApplication].keyWindow.rootViewController;

補(bǔ)充：

YZLoginViewController *yzLoginVc = [YZLoginViewController new];//找根控制器方法//1.找到appdelegate然后獲取window屬性AppDelegate *delegate = (AppDelegate *)[UIApplicationsharedApplication].delegate;[delegate.window.rootViewController presentViewController:yzLoginVc animated:YEScompletion:nil];//2.直接通過(guò)keyWindow來(lái)找根控制器YZYuQingViewController *rootVc = (YZYuQingViewController *)[UIApplicationsharedApplication].keyWindow.rootViewController;[rootVc presentViewController:yzLoginVc animated:YEScompletion:nil];

鏈接：http://www.itdecent.cn/p/157cab691ad2