Ios7 编程自动布局问题

我正在尝试使用自动布局约束实现动态布局；为此，我创建了3个容器视图。第一个是49高，宽度灵活。第二个是320高320宽，最后一个是69高灵活宽。这是一段代码，应该把每个视图放在另一个视图的下面

NSDictionary *viewsDictionary = NSDictionaryOfVariableBindings(searchControlsView, workArtView, playBackControlsContainer);
    // Position time search controls

    constraints = [NSLayoutConstraint constraintsWithVisualFormat:@"|[searchControlsView]|"
                                                          options:0
                                                          metrics:nil
                                                            views:viewsDictionary];
    [self.view addConstraints:constraints];
    constraints = [NSLayoutConstraint constraintsWithVisualFormat:@"V:|[searchControlsView]"
                                                          options:0
                                                          metrics:nil
                                                            views:viewsDictionary];
    [self.view addConstraints:constraints];

    // position workArt
    constraints = [NSLayoutConstraint constraintsWithVisualFormat:@"|[workArtView]|"
                                                          options:0
                                                          metrics:nil
                                                            views:viewsDictionary];
    [self.view addConstraints:constraints];

    constraints = [NSLayoutConstraint constraintsWithVisualFormat:@"V:[searchControlsView]-0-[workArtView]"
                                                          options:0
                                                          metrics:nil
                                                            views:viewsDictionary];
    [self.view addConstraints:constraints];

    // position bottom controls
    constraints = [NSLayoutConstraint constraintsWithVisualFormat:@"|[playBackControlsContainer]|"
                                                          options:0
                                                          metrics:nil
                                                            views:viewsDictionary];
    [self.view addConstraints:constraints];

    constraints = [NSLayoutConstraint constraintsWithVisualFormat:@"V:[workArtView]-(>=0)-[playBackControlsContainer]|" options:0 metrics:nil views:viewsDictionary];
    [self.view addConstraints:constraints];

我想实现的是，如果可能的话，最后一个视图将位于第二个视图的下方，如果可能的话，第三个视图将在整个屏幕的底部对齐，并与第二个视图重叠。但是，第三个视图（playBackControlsContainer）未显示在屏幕中

在此之前，我删除了视图中的所有约束。我尝试了几件事，但我只是从程序约束开始，我无法意识到我失败的地方。。。除此之外，调试日志还有很多额外的视图，并且没有每个控件地址的标识符，因此很难找出我的布局可能不明确的原因。下面是调试日志，以防出错

*<UIWindow:0xc1a6510> - AMBIGUOUS LAYOUT
|   *<UILayoutContainerView:0xc1b6b50>
|   |   *<UITransitionView:0xc1a3da0>
|   |   |   *<UIViewControllerWrapperView:0xc3b82b0>
|   |   |   |   *<UIView:0xc1b9830>
|   |   |   |   |   *<UILayoutContainerView:0xc1ba6a0>
|   |   |   |   |   |   *<UINavigationTransitionView:0xc1bf490>
|   |   |   |   |   |   |   *<UIViewControllerWrapperView:0xc1c5110>
|   |   |   |   |   |   |   |   *<UIView:0xb478820> - AMBIGUOUS LAYOUT
|   |   |   |   |   |   |   |   |   *<UIView:0xb4f9d70> - AMBIGUOUS LAYOUT
|   |   |   |   |   |   |   |   |   |   *<UIButton:0xb4f3e40>
|   |   |   |   |   |   |   |   |   |   |   <UIImageView:0xc4e7030>
|   |   |   |   |   |   |   |   |   |   *<UIButton:0xb4f5440>
|   |   |   |   |   |   |   |   |   |   |   <UIImageView:0xc14b0a0>
|   |   |   |   |   |   |   |   |   |   |   *<UIButtonLabel:0xb4fb610> - AMBIGUOUS LAYOUT
|   |   |   |   |   |   |   |   |   |   *<UIButton:0xb4f0e80>
|   |   |   |   |   |   |   |   |   |   |   <UIImageView:0xc1f00b0>
|   |   |   |   |   |   |   |   |   |   |   *<UIButtonLabel:0xb4fac70> - AMBIGUOUS LAYOUT
|   |   |   |   |   |   |   |   |   |   *<UIButton:0xb4f04f0>
|   |   |   |   |   |   |   |   |   |   |   <UIImageView:0xc129480>
|   |   |   |   |   |   |   |   |   |   |   *<UIButtonLabel:0xb4fa2e0> - AMBIGUOUS LAYOUT
|   |   |   |   |   |   |   |   |   *<UIView:0xb478790>
|   |   |   |   |   |   |   |   |   |   *<UIImageView:0xb4f9b60>
|   |   |   |   |   |   |   |   |   |   *<LVStopWatchLabel:0xb479200>
|   |   |   |   |   |   |   |   |   |   |   <UIImageView:0xb478920>
|   |   |   |   |   |   |   |   |   *<UIView:0xb479940>
|   |   |   |   |   |   |   |   |   |   *<UIButton:0xb4f6ab0>
|   |   |   |   |   |   |   |   |   |   |   <UIImageView:0xc4e6c00>
|   |   |   |   |   |   |   |   |   |   *<UILabel:0xb479db0>
|   |   |   |   |   |   |   |   |   |   *<UISlider:0xb4f5e90>
|   |   |   |   |   |   |   |   |   |   |   <UIView:0xc4e05e0>
|   |   |   |   |   |   |   |   |   |   |   |   <UIView:0xc4e0760>
|   |   |   |   |   |   |   |   |   |   |   |   |   <UIView:0xc4e0880>
|   |   |   |   |   |   |   |   |   |   |   |   <UIView:0xc4e5c40>
|   |   |   |   |   |   |   |   |   |   |   <UIImageView:0xc4e67d0>
|   |   |   |   |   |   |   |   |   |   |   |   <UIImageView:0xc4e5d40>
|   |   |   |   |   |   |   |   |   *<_UILayoutGuide:0xb478440> - AMBIGUOUS LAYOUT
|   |   |   |   |   |   |   |   |   *<_UILayoutGuide:0xb4782a0> - AMBIGUOUS LAYOUT
|   |   |   |   |   |   <UINavigationBar:0xc1c4a10>
|   |   |   |   |   |   |   <_UINavigationBarBackground:0xc1c7530>
|   |   |   |   |   |   |   |   <UIImageView:0xc1c7810>
|   |   |   |   |   |   |   <UINavigationItemView:0xc4cf610>
|   |   |   |   |   |   |   |   <UILabel:0xc4dcae0>
|   |   |   |   |   |   |   <UINavigationItemButtonView:0xc4dcf10>
|   |   |   |   |   |   |   |   <UILabel:0xc4dcfe0>
|   |   |   |   |   |   |   <_UINavigationBarBackIndicatorView:0xc3c3880>
|   |   |   |   |   <GADBannerView:0xc3de310>
|   |   |   |   |   |   <GADWebView:0xc3de440>
|   |   |   |   |   |   |   <_UIWebViewScrollView:0xc3e01a0>
|   |   |   |   |   |   |   |   <UIWebBrowserView:0xd280600>
|   |   |   |   |   <ADBannerView:0xc19ad20>
|   |   |   |   |   |   <ADRemoteView:0xc19cca0>
|   |   |   |   |   |   <UIView:0xc19d590>
|   |   <UITabBar:0xb4a47e0>
|   |   |   <_UITabBarBackgroundView:0xc47db60>
|   |   |   |   <_UIBackdropView:0xc47d240>
|   |   |   |   |   <_UIBackdropEffectView:0xc47e490>
|   |   |   |   |   <UIView:0xc47e530>
|   |   |   <UITabBarButton:0xc19ed40>
|   |   |   |   <UITabBarSwappableImageView:0xc17ee00>
|   |   |   |   <UITabBarButtonLabel:0xc19f170>
|   |   |   <UITabBarButton:0xc1a4120>
|   |   |   |   <UITabBarSwappableImageView:0xc1a3570>
|   |   |   |   <UITabBarButtonLabel:0xc1a3e60>
|   |   |   <UITabBarButton:0xc1a62b0>
|   |   |   |   <UITabBarSwappableImageView:0xc1a6660>
|   |   |   |   <UITabBarButtonLabel:0xc1a6390>
|   |   |   <UITabBarButton:0xc1a8a30>
|   |   |   |   <UITabBarSwappableImageView:0xc1a9080>
|   |   |   |   <UITabBarButtonLabel:0xc1a8f60>
|   |   |   <UIImageView:0xc47ead0>

*-不明确的布局
|   *
|   |   *
|   |   |   *
|   |   |   |   *
|   |   |   |   |   *
|   |   |   |   |   |   *
|   |   |   |   |   |   |   *
|| | | | | |*-不明确的布局
|| | | | | | |*-布局不明确
|   |   |   |   |   |   |   |   |   |   *
|   |   |   |   |   |   |   |   |   |   |   
|   |   |   |   |   |   |   |   |   |   *
|   |   |   |   |   |   |   |   |   |   |   
|| | | | | | | | | |*-不明确的布局
|   |   |   |   |   |   |   |   |   |   *
|   |   |   |   |   |   |   |   |   |   |   
|| | | | | | | | | |*-不明确的布局
|   |   |   |   |   |   |   |   |   |   *
|   |   |   |   |   |   |   |   |   |   |   
|| | | | | | | | | |*-不明确的布局
|   |   |   |   |   |   |   |   |   *
|   |   |   |   |   |   |   |   |   |   *
|   |   |   |   |   |   |   |   |   |   *
|   |   |   |   |   |   |   |   |   |   |   
|   |   |   |   |   |   |   |   |   *
|   |   |   |   |   |   |   |   |   |   *
|   |   |   |   |   |   |   |   |   |   |   
|   |   |   |   |   |   |   |   |   |   *
|   |   |   |   |   |   |   |   |   |   *
|   |   |   |   |   |   |   |   |   |   |   
|   |   |   |   |   |   |   |   |   |   |   |   
|   |   |   |   |   |   |   |   |   |   |   |   |   
|   |   |   |   |   |   |   |   |   |   |   |   
|   |   |   |   |   |   |   |   |   |   |   
|   |   |   |   |   |   |   |   |   |   |   |   
|| | | | | | |*-布局不明确
|| | | | | | |*-布局不明确
|   |   |   |   |   |   
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如果有人能帮我找出原因，我会非常感激。

---

谢谢。

我想你忘了设定你观点的高度

比如说,

constraints = [NSLayoutConstraint constraintsWithVisualFormat:@"V:|[searchControlsView(49)]" options:0 metrics:nil views:viewsDictionary];

---

嗯，高度和宽度约束是使用interface builder添加到每个视图的。即使我从superview中删除了约束，也应该存在。好的，那么我需要更多信息。我没有一个完整的画面的约束在发挥作用。因为您使用的是可视化格式语言，所以我认为布局仅由上面的代码定义。