UIPickerController 留下黑色底栏答案

【问题标题】：UIPickerController leaves black bottom barUIPickerController 留下黑色底栏
【发布时间】：2016-01-04 13:59:37
【问题描述】：

我正在使用以下代码来显示 UIPickerController 及其覆盖视图：

-(void) viewDidLoad{
    self.overlayView = [[OverlayViewController alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
    self.overlayView.delegate = self;
    if ([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera])
    {
        imagePickerController = [[UIImagePickerController alloc] init];
        imagePickerController.sourceType = UIImagePickerControllerSourceTypeCamera;
        imagePickerController.modalPresentationStyle = UIModalPresentationFullScreen;
        imagePickerController.cameraOverlayView.frame=self.view.frame;
        imagePickerController.showsCameraControls = NO;
        imagePickerController.navigationBarHidden = YES;
        imagePickerController.toolbarHidden = YES;
    //imagePickerController.cameraViewTransform = CGAffineTransformScale(imagePickerController.cameraViewTransform, 1.0, 1.3);
        imagePickerController.delegate = self.overlayView;
        // as a delegate we will be notified when pictures are taken and when to dismiss the image picker

        [self.view addSubview:imagePickerController.view];
        imagePickerController.cameraOverlayView =self.overlayView.view;
    } else {
        [self.view addSubview:self.overlayView.view];

    }
 }

然而，当 iPhone 保持纵向时，屏幕底部会显示一个黑条。正如您在附加的屏幕截图中看到的那样，没有横栏出现。如何解决？

【问题讨论】：

似乎overlayView是通过程序创建的，您需要调整overlayView的Mode（Scale to Fill、Aspect Fit等）或调整相机视图的大小。在您的纵向屏幕截图中，相机视图适合主视图并且您会看到黑条，因为相机 (4:3) 和 iPhone 屏幕 (16:9) 的纵横比不同。在您的横向屏幕截图中，相机视图似乎被缩放以填充屏幕，但图像在顶部和底部被裁剪。
那我应该怎么做呢？我不能依靠未来设备的最终尺寸来正确地冻结屏幕……难道没有办法只填满屏幕吗？
overlayView 的 A 坦率地说，除了以编程方式创建它之外，我没有其他方法可以创建它。甚至 UIImagePicker 控制器都没有对应的 Storyboard，它的 overlayView 怎么说？！

标签： ios iphone uiimagepickercontroller

【解决方案1】：

我认为这个问题：How to get the custom overlay for UIImagePicker camera to be full screen in iOS 7? 是同一个问题，你可以在那里找到答案。

【讨论】：

【解决方案2】：

在情节提要中插入 viewController 后，我按照线程中的建议实现了它：

-(void) viewDidLoad{
     self.overlayView = [[OverlayViewController alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
     self.overlayView.delegate = self;
     if ([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera])
     {
         imagePickerController = [[UIImagePickerController alloc] init];
         imagePickerController.sourceType = UIImagePickerControllerSourceTypeCamera;
         imagePickerController.modalPresentationStyle = UIModalPresentationFullScreen;
         imagePickerController.cameraOverlayView.frame=self.view.frame;
         imagePickerController.showsCameraControls = NO;
         imagePickerController.navigationBarHidden = YES;
         imagePickerController.toolbarHidden = YES;

         //imagePickerController.cameraViewTransform = CGAffineTransformScale(imagePickerController.cameraViewTransform, 1.0, 1.3);
         imagePickerController.delegate = self.overlayView;
         // as a delegate we will be notified when pictures are taken and when to dismiss the image picker
         self.overlayView=[self.storyboard instantiateViewControllerWithIdentifier:@"OverlayViewController"];
         [self.view addSubview:imagePickerController.view];
         [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(showSlider) name:@"showSlider" object:nil];
         imagePickerController.cameraOverlayView =self.overlayView.view;
         CGSize screenSize = [[UIScreen mainScreen] bounds].size;
         float cameraAspectRatio = 4.0 / 4.0; //! Note: 4.0 and 4.0 works
         float imageWidth = floorf(screenSize.width * cameraAspectRatio);
         float scale = ceilf((screenSize.height / imageWidth) * 10.0) / 10.0;
         self.imagePickerController.cameraViewTransform = CGAffineTransformMakeScale(scale, scale);
      } else {
         [self.view addSubview:self.overlayView.view]; 
    }
 }

事实上，在将 cameraAspectRatio 调整为 4.0、4.0 后，一切正常。然而，当以横向显示应用程序时，图像和控件会颠倒过来。这就是我的门把手显示的方式。此外，当我将 iPhone 指向上方时，图像会横向移动，反之亦然。它可以修复还是我需要放弃横向选项？

【讨论】：

【解决方案3】：

对于任何可以使用它的人来说，他就是swift中的代码：

@IBAction func takePhoto(_ sender: Any) {
    imagePicker =  UIImagePickerController()
    imagePicker.delegate = self
    imagePicker.sourceType = .camera
    imagePicker.cameraCaptureMode = .photo
    imagePicker.cameraDevice = .front
    imagePicker.cameraOverlayView?.frame = view.frame
    imagePicker.showsCameraControls = false
    imagePicker.isNavigationBarHidden = true
    imagePicker.isToolbarHidden = true
    let screenSize = UIScreen.main.bounds.size
    let cameraAspectRatio: Float = 4.0 / 4.0
    let imageWidth = floorf(Float(screenSize.width * CGFloat(cameraAspectRatio)))
    let scale = ((screenSize.height / CGFloat(imageWidth)) * 10.0).rounded() / 10.0;
    imagePicker.cameraViewTransform = CGAffineTransform(scaleX: CGFloat(scale), y: CGFloat(scale))
    

    present(imagePicker, animated: false, completion: nil)
}

我的情况是，我通过按钮调用此屏幕。

【讨论】：