185

我有一个UIImageView，我希望能够调整大小和旋转等。

可以UIGestureRecognizer添加到UIImageView?

我想将旋转和捏合识别器添加到UIImageView将在运行时创建的。

如何添加这些识别器？

4

8 回答 8

433

检查userInteractionEnabled是否YES在UIImageView. 然后你可以添加一个手势识别器。

imageView.userInteractionEnabled = YES;
UIPinchGestureRecognizer *pgr = [[UIPinchGestureRecognizer alloc] 
    initWithTarget:self action:@selector(handlePinch:)];
pgr.delegate = self;
[imageView addGestureRecognizer:pgr];
[pgr release];
:
:
- (void)handlePinch:(UIPinchGestureRecognizer *)pinchGestureRecognizer
{
  //handle pinch...
}
于 2010-10-11T16:11:57.123 回答
76

是的，可以将 UIGestureRecognizer 添加到 UIImageView。如另一个答案中所述，记住通过将其userInteractionEnabled属性设置为来启用图像视图上的用户交互非常重要YES。UIImageView 继承自 UIView，UIView 的用户交互属性YES默认设置为，而 UIImageView 的用户交互属性NO默认设置为。

从UIImageView 文档：

新的图像视图对象默认配置为忽略用户事件。如果要在 UIImageView 的自定义子类中处理事件，则必须在初始化对象后将 userInteractionEnabled 属性的值显式更改为 YES。

无论如何，关于大部分答案。下面是一个如何UIImageView使用 a UIPinchGestureRecognizer、 aUIRotationGestureRecognizer和 a创建 a 的示例UIPanGestureRecognizer。

首先，在viewDidLoad或您选择的其他方法中，创建一个图像视图，给它一个图像，一个框架，并启用它的用户交互。然后如下创建三个手势。一定要利用他们的委托属性（很可能设置为自我）。这将需要同时使用多个手势。

- (void)viewDidLoad
{
    [super viewDidLoad];

    // set up the image view
    UIImageView *imageView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"someImage"]];
    [imageView setBounds:CGRectMake(0.0, 0.0, 120.0, 120.0)];
    [imageView setCenter:self.view.center];
    [imageView setUserInteractionEnabled:YES]; // <--- This is very important

    // create and configure the pinch gesture
    UIPinchGestureRecognizer *pinchGestureRecognizer = [[UIPinchGestureRecognizer alloc] initWithTarget:self action:@selector(pinchGestureDetected:)];
    [pinchGestureRecognizer setDelegate:self];
    [imageView addGestureRecognizer:pinchGestureRecognizer];

    // create and configure the rotation gesture
    UIRotationGestureRecognizer *rotationGestureRecognizer = [[UIRotationGestureRecognizer alloc] initWithTarget:self action:@selector(rotationGestureDetected:)];
    [rotationGestureRecognizer setDelegate:self];
    [imageView addGestureRecognizer:rotationGestureRecognizer];

    // creat and configure the pan gesture
    UIPanGestureRecognizer *panGestureRecognizer = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(panGestureDetected:)];
    [panGestureRecognizer setDelegate:self];
    [imageView addGestureRecognizer:panGestureRecognizer];


    [self.view addSubview:imageView]; // add the image view as a subview of the view controllers view
}

以下是检测到视图上的手势时将调用的三个方法。在它们内部，我们将检查手势的当前状态，如果它处于开始或更改状态，UIGestureRecognizerState我们将读取手势的缩放/旋转/平移属性，将该数据应用于仿射变换，将仿射变换应用于图像查看，然后重置手势缩放/旋转/平移。 

- (void)pinchGestureDetected:(UIPinchGestureRecognizer *)recognizer
{
    UIGestureRecognizerState state = [recognizer state];

    if (state == UIGestureRecognizerStateBegan || state == UIGestureRecognizerStateChanged)
    {
        CGFloat scale = [recognizer scale];
        [recognizer.view setTransform:CGAffineTransformScale(recognizer.view.transform, scale, scale)];
        [recognizer setScale:1.0];
    }
}

- (void)rotationGestureDetected:(UIRotationGestureRecognizer *)recognizer
{
    UIGestureRecognizerState state = [recognizer state];

    if (state == UIGestureRecognizerStateBegan || state == UIGestureRecognizerStateChanged)
    {
        CGFloat rotation = [recognizer rotation];
        [recognizer.view setTransform:CGAffineTransformRotate(recognizer.view.transform, rotation)];
        [recognizer setRotation:0];
    }
}

- (void)panGestureDetected:(UIPanGestureRecognizer *)recognizer
{
    UIGestureRecognizerState state = [recognizer state];

    if (state == UIGestureRecognizerStateBegan || state == UIGestureRecognizerStateChanged)
    {
        CGPoint translation = [recognizer translationInView:recognizer.view];
        [recognizer.view setTransform:CGAffineTransformTranslate(recognizer.view.transform, translation.x, translation.y)];
        [recognizer setTranslation:CGPointZero inView:recognizer.view];
    }
}

最后也是非常重要的一点，您需要使用UIGestureRecognizerDelegate方法gestureRecognizer: shouldRecognizeSimultaneouslyWithGestureRecognizer来允许手势同时工作。如果这三个手势是仅有的三个将此类指定为其委托的手势，那么您可以简单地返回YES，如下所示。但是，如果您有其他手势将此类指定为其委托，则可能需要向此方法添加逻辑以确定哪个手势是哪个手势，然后才能让它们一起工作。

- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer
{
    return YES;
}

不要忘记确保您的类符合UIGestureRecognizerDelegate协议。为此，请确保您的界面看起来像这样：

@interface MyClass : MySuperClass <UIGestureRecognizerDelegate>

如果您更喜欢自己在工作示例项目中使用代码，可以在此处找到我创建的包含此代码的示例项目。

于 2013-09-04T19:39:04.340 回答
15

Swift 4.2

myImageView.isUserInteractionEnabled = true
let tapGestureRecognizer = UITapGestureRecognizer(target: self, action: #selector(imageTapped))
tapGestureRecognizer.numberOfTapsRequired = 1
myImageView.addGestureRecognizer(tapGestureRecognizer)

and when tapped:

@objc func imageTapped(_ sender: UITapGestureRecognizer) {
   // do something when image tapped
   print("image tapped")
}
于 2015-04-19T09:01:27.750 回答
11

Swift 2.0 解决方案

您可以在同一个庄园中创建点击、捏合或滑动手势识别器。下面我将引导您完成 4 个步骤，让您的识别器启动并运行。

4个步骤

1.）UIGestureRecognizerDelegate通过将其添加到您的类签名来继承。

class ViewController: UIViewController, UIGestureRecognizerDelegate {...}

2.)控制从图像拖动到 viewController 以创建 IBOutlet：

@IBOutlet weak var tapView: UIImageView!

3.)在您的 viewDidLoad 添加以下代码：

// create an instance of UITapGestureRecognizer and tell it to run 
// an action we'll call "handleTap:"
let tap = UITapGestureRecognizer(target: self, action: Selector("handleTap:"))
// we use our delegate
tap.delegate = self
// allow for user interaction
tapView.userInteractionEnabled = true
// add tap as a gestureRecognizer to tapView
tapView.addGestureRecognizer(tap)

4.)创建当你的手势识别器被点击时将被调用的函数。（如果您选择，您可以排除= nil）。

func handleTap(sender: UITapGestureRecognizer? = nil) {
    // just creating an alert to prove our tap worked!
    let tapAlert = UIAlertController(title: "hmmm...", message: "this actually worked?", preferredStyle: UIAlertControllerStyle.Alert)
    tapAlert.addAction(UIAlertAction(title: "OK", style: .Destructive, handler: nil))
    self.presentViewController(tapAlert, animated: true, completion: nil)
}

您的最终代码应如下所示：

class ViewController: UIViewController, UIGestureRecognizerDelegate {

    @IBOutlet weak var tapView: UIImageView!

    override func viewDidLoad() {
        super.viewDidLoad()

        let tap = UITapGestureRecognizer(target: self, action: Selector("handleTap:"))
        tap.delegate = self
        tapView.userInteractionEnabled = true
        tapView.addGestureRecognizer(tap)
    }

    func handleTap(sender: UITapGestureRecognizer? = nil) {
        let tapAlert = UIAlertController(title: "hmmm...", message: "this actually worked?", preferredStyle: UIAlertControllerStyle.Alert)
        tapAlert.addAction(UIAlertAction(title: "OK", style: .Destructive, handler: nil))
        self.presentViewController(tapAlert, animated: true, completion: nil)
    }
}
于 2015-07-08T02:48:32.047 回答
5

我刚刚通过在单个视图中添加 3 个手势来使用 swift4 完成此操作

  1. UIPinchGestureRecognizer：放大和缩小视图。
  2. UIRotationGestureRecognizer：旋转视图。
  3. UIPanGestureRecognizer：拖动视图。

这是我的示例代码

class ViewController: UIViewController: UIGestureRecognizerDelegate{
      //your image view that outlet from storyboard or xibs file.
     @IBOutlet weak var imgView: UIImageView!
     // declare gesture recognizer
     var panRecognizer: UIPanGestureRecognizer?
     var pinchRecognizer: UIPinchGestureRecognizer?
     var rotateRecognizer: UIRotationGestureRecognizer?

     override func viewDidLoad() {
          super.viewDidLoad()
          // Create gesture with target self(viewcontroller) and handler function.  
          self.panRecognizer = UIPanGestureRecognizer(target: self, action: #selector(self.handlePan(recognizer:)))
          self.pinchRecognizer = UIPinchGestureRecognizer(target: self, action: #selector(self.handlePinch(recognizer:)))
          self.rotateRecognizer = UIRotationGestureRecognizer(target: self, action: #selector(self.handleRotate(recognizer:)))
          //delegate gesture with UIGestureRecognizerDelegate
          pinchRecognizer?.delegate = self
          rotateRecognizer?.delegate = self
          panRecognizer?.delegate = self
          // than add gesture to imgView
          self.imgView.addGestureRecognizer(panRecognizer!)
          self.imgView.addGestureRecognizer(pinchRecognizer!)
          self.imgView.addGestureRecognizer(rotateRecognizer!)
     }

     // handle UIPanGestureRecognizer 
     @objc func handlePan(recognizer: UIPanGestureRecognizer) {    
          let gview = recognizer.view
          if recognizer.state == .began || recognizer.state == .changed {
               let translation = recognizer.translation(in: gview?.superview)
               gview?.center = CGPoint(x: (gview?.center.x)! + translation.x, y: (gview?.center.y)! + translation.y)
               recognizer.setTranslation(CGPoint.zero, in: gview?.superview)
          }
     }

     // handle UIPinchGestureRecognizer 
     @objc func handlePinch(recognizer: UIPinchGestureRecognizer) {
          if recognizer.state == .began || recognizer.state == .changed {
               recognizer.view?.transform = (recognizer.view?.transform.scaledBy(x: recognizer.scale, y: recognizer.scale))!
               recognizer.scale = 1.0
         }
     }   

     // handle UIRotationGestureRecognizer 
     @objc func handleRotate(recognizer: UIRotationGestureRecognizer) {
          if recognizer.state == .began || recognizer.state == .changed {
               recognizer.view?.transform = (recognizer.view?.transform.rotated(by: recognizer.rotation))!
               recognizer.rotation = 0.0
           }
     }

     // mark sure you override this function to make gestures work together 
     func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldRecognizeSimultaneouslyWith otherGestureRecognizer: UIGestureRecognizer) -> Bool {
         return true
     }

}

有任何问题，只需输入评论即可。谢谢你

于 2017-07-07T17:42:25.213 回答
2

您还可以将点击手势识别器拖到 中的图像视图中Storyboard。ctrl + drag然后通过代码创建一个动作。

于 2015-11-26T18:36:37.473 回答
2

SWIFT 3 示例

override func viewDidLoad() {

    self.backgroundImageView.addGestureRecognizer(
        UITapGestureRecognizer.init(target: self, action:#selector(didTapImageview(_:)))
    )

    self.backgroundImageView.isUserInteractionEnabled = true
}

func didTapImageview(_ sender: Any) {
    // do something
}

必要时没有手势识别器委托或其他实现。

于 2016-12-22T19:17:03.850 回答
1

对于 Blocks 爱好者，您可以使用ALActionBlocks在块中添加手势动作

__weak ALViewController *wSelf = self;
imageView.userInteractionEnabled = YES;
UITapGestureRecognizer *gr = [[UITapGestureRecognizer alloc] initWithBlock:^(UITapGestureRecognizer *weakGR) {
    NSLog(@"pan %@", NSStringFromCGPoint([weakGR locationInView:wSelf.view]));
}];
[self.imageView addGestureRecognizer:gr];
于 2016-12-27T14:56:35.633 回答