UIViewController didRotateFromInterfaceOrientation：没有被调用答案

【问题标题】：UIViewController didRotateFromInterfaceOrientation: not being calledUIViewController didRotateFromInterfaceOrientation：没有被调用
【发布时间】：2014-03-03 10:05:36
【问题描述】：

我正在编写一个 iOS 游戏应用程序，其中一些视图在屏幕上飞来飞去，应该可以在横向和纵向模式下玩。对于较旧的设备，出于性能原因，我决定在界面旋转正在进行时停止动画。应该按照苹果文档https://developer.apple.com/library/mac/documentation/cocoa/conceptual/coreanimation_guide/AdvancedAnimationTricks/AdvancedAnimationTricks.html 中的描述停止和继续动画，效果很好。所以我决定在willRotateToInterfaceOrientation: (UIInterfaceOrientation) toInterfaceOrientation duration: (NSTimeInterval) duration 中暂停动画并在didRotateFromInterfaceOrientation: (UIInterfaceOrientation) fromInterfaceOrientation 中恢复它。问题是，如果我将视图的图层速度设置为零，则永远不会调用 didRotateFromInterfaceOrientation: (UIInterfaceOrientation) fromInterfaceOrientation。有人对这种奇怪的行为有解释吗？

我在做的细节是：

SGMathsMasterNoteView *noteView = [SGMathsMasterNoteView noteViewWithExercise: self.nextExercise andDelegate: self];
[self.animationContainer insertSubview: noteView aboveSubview: self.noteStackView];
[noteView startAnimation];

SGMathsMasterNoteView.m

- (void) startAnimation {
    self.frame = self.noteAnimationView.noteStackView.frame;
    CAAnimation *ani = self.noteAnimationView.motionAnimation;
    [self.layer addAnimation: ani forKey: @"fly"];
    self.layer.speed = 1.0;
    self.center = self.noteAnimationView.destroyPoint;
}

- (void) pauseAnimation {
    self.layer.speed = 0.0;
    self.layer.timeOffset = [layer convertTime:CACurrentMediaTime() fromLayer:nil];
}

- (void) resumeAnimation {
   CFTimeInterval pausedTime = self.layer.timeOffset;
   self.layer.speed = 1.0;
   self.layer.timeOffset = 0.0;
   self.layer.beginTime = 0.0;
   CFTimeInterval timeSincePause = [layer convertTime:CACurrentMediaTime() fromLayer:nil] - pausedTime;
   self.layer.beginTime = timeSincePause;
}

SGGameViewController.m

- (void) willRotateToInterfaceOrientation: (UIInterfaceOrientation) toInterfaceOrientation duration: (NSTimeInterval) duration {
   for (SGMathsMasterNoteView *noteView in [self.animationContainer.subviews allObjectsOfClass: [SGMathsMasterNoteView class]]) {
      [noteView pauseAnimation];
   }
}

- (void) didRotateFromInterfaceOrientation: (UIInterfaceOrientation) fromInterfaceOrientation {
   for (SGMathsMasterNoteView *noteView in [self.animationContainer.subviews allObjectsOfClass: [SGMathsMasterNoteView class]]) {
      [noteView resumeAnimation];
   }
}

【问题讨论】：

标签： ios objective-c uiviewcontroller quartz-core

【解决方案1】：

乍一看，您的 willRotateToInterfaceOrientation:duration: 和 didRotateFromInterfaceOrientation: 方法不会调用 super，这是必需的。我的猜测是，由于 super 在旋转之前没有被调用，它会阻止调用 post-rotation 方法。

来自UIViewController 类参考：

此方法的实现必须在某些时候调用 super 在执行期间。

这是您的实现的更正版本：

- (void) willRotateToInterfaceOrientation: (UIInterfaceOrientation) toInterfaceOrientation duration: (NSTimeInterval) duration
{
    [super willRotateToInterfaceOrientation: toInterfaceOrientation duration: duration];

    for (SGMathsMasterNoteView *noteView in [self.animationContainer.subviews allObjectsOfClass: [SGMathsMasterNoteView class]])
    {
        [noteView pauseAnimation];
    }
}

- (void) didRotateFromInterfaceOrientation: (UIInterfaceOrientation) fromInterfaceOrientation
{
    [super didRotateFromInterfaceOrientation: fromInterfaceOrientation];

    for (SGMathsMasterNoteView *noteView in [self.animationContainer.subviews allObjectsOfClass: [SGMathsMasterNoteView class]])
    {
        [noteView resumeAnimation];
    }
}

我先打电话给super，然后试着在最后打电话。

希望能解决您的问题。

【讨论】：