ios UIView 确实出现了？
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UIView did appear?
提问by nosuic
I'm wondering, is there a way to get a delegate or something, when a particular UIViewhas been shown on the screen ?
我想知道，当UIView屏幕上显示特定内容时，有没有办法获得代表或其他东西？
回答by Max
Try these:
试试这些：
– didAddSubview:
– willRemoveSubview:
– willMoveToSuperview:
– didMoveToSuperview
– willMoveToWindow:
– didMoveToWindow
- viewDidAppear:
回答by David 'mArm' Ansermot
If you manage your logic directly inside the UIView, use:
如果您直接在 UIView 内部管理逻辑，请使用：
- didMoveToSuperview
If you manage your logic inside a UIViewController, use :
如果您在 UIViewController 中管理您的逻辑，请使用：
- viewDidAppear:(BOOL)animated
回答by buxik
Swift version. Inside your UIView class just:
迅捷版。在您的 UIView 类中：
override func willMove(toWindow newWindow: UIWindow?) {
super.willMove(toWindow: newWindow)
if newWindow == nil {
// UIView disappear
} else {
// UIView appear
}
}
回答by Jacob Relkin
If you are managing the UIViewvia a UIViewController, then you can use the -viewDidAppear:method:
如果您UIView通过 a管理UIViewController，那么您可以使用以下-viewDidAppear:方法：
- (void) viewDidAppear:(BOOL) animated {
//do stuff...
[super viewDidAppear:animated];
}
回答by Ben
Another way to find out when a control is on screen is to subclass the View or Control and override drawRect...
找出控件何时出现在屏幕上的另一种方法是将 View 或 Control 子类化并覆盖drawRect...
However, it's called when it's drawn and not only when first shown. So it's only sometimes what you want. It worked for my case. Make sure to call super as well! =)
但是，它在绘制时被调用，而不仅仅是在第一次显示时调用。所以这只是有时你想要的。它适用于我的情况。一定要打电话给超级！=)
