iOS - 如何检查模态视图是否存在
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iOS - How to check if a modal view is present
提问by Evan Johnson
Is there a way to check if a modal view is present? I'd like to run a method only if a modal view is present. Also, if I have multiple modal views, is there a way to check if a certain modal view is present.
有没有办法检查模态视图是否存在？仅当存在模态视图时，我才想运行一个方法。另外，如果我有多个模态视图，有没有办法检查某个模态视图是否存在。
I use the following code to present and dismiss modal views:
我使用以下代码来呈现和关闭模态视图：
[self presentModalViewController:myModalView animated:YES];
[self dismissModalViewControllerAnimated:YES];
Thank you in advance!
先感谢您！
Cheers, Evan
干杯，埃文
PS. My modal view has a view controller, but I'd like to check if the modal view is present from a separate class that is running asynchronously.
附注。我的模态视图有一个视图控制器，但我想检查模态视图是否存在于异步运行的单独类中。
回答by arlomedia
Are you checking the presence of a modal view controller from the parent view controller? If so, you can just check that view controller's modalViewController property:
您是否从父视图控制器检查模态视图控制器的存在？如果是这样，您可以检查该视图控制器的 modalViewController 属性：
BOOL modalPresent = (self.modalViewController);
If you want to check for a particular modal view controller, you can get the modal view controller's class name like this:
如果你想检查一个特定的模态视图控制器，你可以像这样获得模态视图控制器的类名：
NSString *modalClassName = NSStringFromClass([self.modalViewController class]);
回答by tipycalFlow
You can check using: self.presentedViewController, which returns The view controller that is presented by this view controller, or one of its ancestors in the view controller hierarchy.
您可以检查使用：self.presentedViewController，它返回The view controller that is presented by this view controller, or one of its ancestors in the view controller hierarchy.
回答by mixtly87
What worked for me is following:
对我有用的是：
// this is the trick: set parent view controller as application's window root view controller
UIApplication.sharedApplication.delegate.window.rootViewController = viewController;
// assert no modal view is presented
XCTAssertNil(viewController.presentedViewController);
// simulate button tap which shows modal view controller
[viewController.deleteButton sendActionsForControlEvents:UIControlEventTouchUpInside];
// assert that modal view controller is presented
XCTAssertEqualObjects(viewController.presentedViewController.class, MyModalViewController.class);
As far as I tested it, this works for iOS7 and iOS8. Didn't try on iOS6 however.
据我测试，这适用于 iOS7 和 iOS8。然而没有在iOS6上尝试。
回答by Binoy jose
You can check the presence of a modal view controllerfrom the parent view controller
您可以view controller从父级检查模态的存在view controller
if ( [[self presentingViewController] presentingViewController] ) {
}
