我有一个名为 PhotoBoothController 的类，我用它来使用手势操作图像。当我在 iPhone 上运行它时它工作正常。但是，当我在 iPad 上运行它时，我会在 UIPopoverController 中显示 PhotoBoothController。图像看起来很好，但是我无法操纵它，因为我的手势似乎没有被识别。我不确定如何让 UIPopoverController 控制手势。

我呈现 popovercontroller 并配置 View :

- (void)presentPhotoBoothForPhoto:(UIImage *)photo button:(UIButton *)button {

    //Create a photoBooth and set its contents
    PhotoBoothController *photoBoothController = [[PhotoBoothController alloc] init];
    photoBoothController.photoImage.image = [button backgroundImageForState:UIControlStateNormal];

    //set up all the elements programmatically.
    photoBoothController.view.backgroundColor = [UIColor whiteColor];

    //Add frame (static)
    UIImage *frame = [[UIImage imageNamed:@"HumptyLine1Frame.png"] adjustForResolution];
    UIImageView *frameView = [[UIImageView alloc] initWithImage:frame];
    frameView.frame = CGRectMake(50, 50, frame.size.width, frame.size.height);
    [photoBoothController.view addSubview:frameView];

    //Configure image
    UIImageView *photoView = [[UIImageView alloc] initWithImage:photo];
    photoView.frame = CGRectMake(50, 50, photo.size.width, photo.size.height);
    photoBoothController.photoImage = photoView;

    //Add canvas
    UIView *canvas = [[UIView alloc] initWithFrame:frameView.frame];
    photoBoothController.canvas = canvas;
    [canvas addSubview:photoView];
    [canvas becomeFirstResponder];

    [photoBoothController.view addSubview:canvas];
    [photoBoothController.view bringSubviewToFront:frameView];

    //resize the popover view shown in the current view to the view's size
    photoBoothController.contentSizeForViewInPopover = CGSizeMake(frameView.frame.size.width+100, frameView.frame.size.height+400);

    self.photoBooth = [[UIPopoverController alloc] initWithContentViewController:photoBoothController];
    [self.photoBooth presentPopoverFromRect:button.frame
                                     inView:self.view
                   permittedArrowDirections:UIPopoverArrowDirectionAny
                                   animated:YES];
}

我认为 [canvas becomeFirstResponder] 可能会这样做，但它似乎没有什么不同。

非常感谢任何建议，谢谢。

更新:根据评论添加代码

- (void)viewDidLoad {
  [super viewDidLoad];

  if (!_marque) {
    _marque = [CAShapeLayer layer];
    _marque.fillColor = [[UIColor clearColor] CGColor];
    _marque.strokeColor = [[UIColor grayColor] CGColor];
    _marque.lineWidth = 1.0f;
    _marque.lineJoin = kCALineJoinRound;
    _marque.lineDashPattern = [NSArray arrayWithObjects:[NSNumber numberWithInt:10],[NSNumber numberWithInt:5], nil];
    _marque.bounds = CGRectMake(photoImage.frame.origin.x, photoImage.frame.origin.y, 0, 0);
    _marque.position = CGPointMake(photoImage.frame.origin.x + canvas.frame.origin.x, photoImage.frame.origin.y + canvas.frame.origin.y);
  }
  [[self.view layer] addSublayer:_marque];

  UIPinchGestureRecognizer *pinchRecognizer = [[UIPinchGestureRecognizer alloc] initWithTarget:self action:@selector(scale:)];
  [pinchRecognizer setDelegate:self];
  [self.view addGestureRecognizer:pinchRecognizer];

  UIRotationGestureRecognizer *rotationRecognizer = [[UIRotationGestureRecognizer alloc] initWithTarget:self action:@selector(rotate:)];
  [rotationRecognizer setDelegate:self];
  [self.view addGestureRecognizer:rotationRecognizer];

  UIPanGestureRecognizer *panRecognizer = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(move:)];
  [panRecognizer setMinimumNumberOfTouches:1];
  [panRecognizer setMaximumNumberOfTouches:1];
  [panRecognizer setDelegate:self];
  [canvas addGestureRecognizer:panRecognizer];

  UITapGestureRecognizer *tapProfileImageRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(tapped:)];
  [tapProfileImageRecognizer setNumberOfTapsRequired:1];
  [tapProfileImageRecognizer setDelegate:self];
  [canvas addGestureRecognizer:tapProfileImageRecognizer];

}

- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer {
  return ![gestureRecognizer isKindOfClass:[UIPanGestureRecognizer class]] && ![gestureRecognizer isKindOfClass:[UITapGestureRecognizer class]];
}

最佳答案

我正在开发一个类似的应用程序，我可以轻松地在 Canvas 上操作图像。

1) 检查canvas的userInteractionEnabled属性是否设置为YES。
2) 您可以尝试将手势添加到 ImageView 而不是 Canvas 。 (我猜你想缩放，旋转 n 滑动图像)。

关于objective-c - 在 UIPopoverController 中丢失手势识别器，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/10452075/