ios - UIView 动画将 View 重置为原始矩形

Question

我正在尝试在点击链接时从右边框将 UIWebView 动画化到屏幕上。为此，我使用了两个 UIView。一个称为 onScreenWebView，另一个称为 offScreenWebView。我的想法是，我可以将 offscreenWebView 从右侧动画化到屏幕上，并将 onScreenWebView 动画化到离开屏幕到左侧。然后交换 View (因此屏幕上的 View 变为 onScreenWebView，反之亦然)但我的动画有问题。我必须指出，它在第一次使用时效果很好。之后，它根本无法正常工作。

View 是这样对齐的

      __________ __________
      |        | |        |
      |   on   | |  off   |
      | screen | | screen |
      |________| |________|

这是动画代码:

offScreenWebView.hidden = true;

offScreenWebView.frame = self.frame;
[offScreenWebView offSetX:self.bounds.size.width + kOffsetPadding];         // move offscreen to the right
[self logWebRects:@"begin"];
offScreenWebView.hidden = false;
[self bringSubviewToFront:offScreenWebView];

[UIView animateWithDuration:0.5f delay:0.0f options:UIViewAnimationCurveEaseInOut animations:^{
    [self logWebRects:@"during 1"];
    offScreenWebView.frame = self.frame;
    onScreenWebView.frame = CGRectMake(-(self.bounds.size.width + kOffsetPadding), 0, onScreenWebView.bounds.size.width, onScreenWebView.bounds.size.height);
    [self logWebRects:@"during 2"];
}completion:^(BOOL finished) {
    [self logWebRects:@"finished b4 swap"];
    [self swapWebViews];
    [self logWebRects:@"finished -- done"];
}];

这是我的 logWebRects 方法的输出(只是每个 View 的来源)

Navigation Type ::      Link Clicked
Rect of self frame   ::  {{0, 0}, {320, 460}} 

99  --  Point of offscreen origin   begin          ::  {335, 0}
0   --  Point of onscreen origin    begin          ::  {0, 0}
99  --  Point of offscreen origin   during 1       ::  {335, 0}
0   --  Point of onscreen origin    during 1       ::  {0, 0}
99  --  Point of offscreen origin   during 2       ::  {0, 0}
0   --  Point of onscreen origin    during 2       ::  {-335, 0}
Navigation Type ::      Other
99  --  Point of offscreen origin   finished b4 swap       ::  {0, 0}
0   --  Point of onscreen origin    finished b4 swap       ::  {-335, 0}
0   --  Point of offscreen origin   finished -- done       ::  {-335, 0}
99  --  Point of onscreen origin    finished -- done       ::  {0, 0}


Navigation Type ::      Link Clicked
Rect of self frame   ::  {{0, 0}, {320, 460}} 

0   --  Point of offscreen origin   begin          ::  {335, 0}
99  --  Point of onscreen origin    begin          ::  {0, 0}
0   --  Point of offscreen origin   during 1       ::  {335, 0}
99  --  Point of onscreen origin    during 1       ::  {0, 0}
0   --  Point of offscreen origin   during 2       ::  {0, 0}
99  --  Point of onscreen origin    during 2       ::  {-335, 0}
Navigation Type ::      Other
0   --  Point of offscreen origin   finished b4 swap       ::  {335, 0}
99  --  Point of onscreen origin    finished b4 swap       ::  {0, 0}
99  --  Point of offscreen origin   finished -- done       ::  {0, 0}
0   --  Point of onscreen origin    finished -- done       ::  {335, 0}

这些日志来自初始运行。然后也是第二轮。您会注意到，无论出于何种原因，动画 block 都会在完成 block 之前重置每个 Web View 的框架。

我应该注意，我使用经典的临时变量交换来交换 Web View 。此外，它们是兄弟 View 。

Answer 1

我知道这有点老了，但我遇到了同样的问题，这是我找到的唯一关于它的帖子。

问题是 bringSubviewToFront 执行隐式动画(我猜)阻止动画 block 分配正确的帧。

我通过禁用隐式动画解决了这个问题。尝试使用这段代码代替普通的 bringSubviewToFront。

[CATransaction begin];
[CATransaction setDisabledActions:YES];
[self bringSubviewToFront:offScreenWebView];
[CATransaction commit];