ios - 动画后移除 UIView 不丢失其他元素

Question

如果我在这两者之间切换数百次会怎样？将成为未使用的 UIView 的左撇子？我的主 UIView 上有几个控件，我想将它们作为一组控件进行动画(向上滑动和向下滑动)几次，然后我决定将它们添加到 UIView 并为该 View 设置动画。但似乎每次当我将 view 添加到 superView 时，它都会保留在那里，如果我运行 [view removeFromSuperView] 它也会删除所有控件我已添加到 View 。它会影响性能还是会导致内存泄漏问题？

 (void)slideUp{
    repeatViewTop = datePickerButton.frame.origin.y;
    UIView *view = [[UIView alloc] initWithFrame:CGRectMake(0, 0, SCREEN_WIDTH, repeatViewTop)];
    [view addSubview:taskTitle];
    [view addSubview:taskNote];
    [view addSubview:datePickerButton];
    [view addSubview:taskSelectedDateViewer];
    [self.view addSubview:view];

    [UIView animateWithDuration:0.4f
                          delay:0.1f
                        options:UIViewAnimationOptionCurveEaseOut
                     animations:^{
                         float tempY=view.frame.origin.y;
                         [view setCenter:CGPointMake(SCREEN_WIDTH/2,tempY)];
                         [view setAlpha:0.4f];
                     }
                     completion:^(BOOL finished){
                     }];
    [self.view insertSubview:view atIndex:0];
}

这将使这些控件向下滑动:

- (void)slideDown{
    taskTitle.userInteractionEnabled=NO;
    //150=view.frame.origin.y after sliding up
    UIView *view = [[UIView alloc] initWithFrame:CGRectMake(0, -114, SCREEN_WIDTH, repeatViewTop)];
    [view addSubview:taskTitle];
    [view addSubview:taskNote];
    [view addSubview:datePickerButton];
    [view addSubview:taskSelectedDateViewer];
    [self.view addSubview:view];

    [UIView animateWithDuration:0.4f
                          delay:0.1f
                        options:UIViewAnimationOptionCurveEaseOut
                     animations:^{
                         float tempY=view.frame.origin.y *(-1);
                         [view setCenter:CGPointMake(SCREEN_WIDTH/2,tempY)];
                         [view setAlpha:1.0f];
                     }
                     completion:^(BOOL finished){


                     }];
    [self.view insertSubview:view atIndex:0];
}

Answer 1

您应该仅在 View 中添加元素一次，并保留对 View 的引用，然后为其设置动画，而不是一直插入。

您可以随时创建 View ，例如在 viewDidLoad 委托(delegate)中，如下所示:

- (void)viewDidLoad {
    //Other code here


    UIView *view = [[UIView alloc] initWithFrame:CGRectMake(0, 0, SCREEN_WIDTH, repeatViewTop)];
    view.tag = 1999;
    [view addSubview:taskTitle];
    [view addSubview:taskNote];
    [view addSubview:datePickerButton];
    [view addSubview:taskSelectedDateViewer];
    [self.view addSubview:view];
}

然后在动画中获取对 View 的引用，如下所示:

(void)slideUp{
    repeatViewTop = datePickerButton.frame.origin.y;
    UIView *view = [self.view viewWithTag:1999];

    [UIView animateWithDuration:0.4f
                          delay:0.1f
                        options:UIViewAnimationOptionCurveEaseOut
                     animations:^{
                         float tempY=view.frame.origin.y;
                         [view setCenter:CGPointMake(SCREEN_WIDTH/2,tempY)];
                         [view setAlpha:0.4f];
                     }
                     completion:^(BOOL finished){
                     }];
}