UITapGestureRecognizer的用法

来源：互联网发布：中经云数据存储编辑：程序博客网时间：2024/05/13 23:18

UIKit中包含了UIGestureRecognizer类，用于检测发生在设备中的手势。UIGestureRecognizer是一个抽象类，定义了所有手势的基本行为，它有下面一些子类用于处理具体的手势：

    1、拍击UITapGestureRecognizer (任意次数的拍击)
    2、向里或向外捏UIPinchGestureRecognizer (用于缩放)
    3、摇动或者拖拽UIPanGestureRecognizer
    4、擦碰UISwipeGestureRecognizer (以任意方向)
    5、旋转UIRotationGestureRecognizer (手指朝相反方向移动)

6、长按UILongPressGestureRecognizer

对于不同类型的手势识别器，具有不同的配置属性。比如UITapGestureRecognizer，可以配置拍击次数。界面接收到手势之后，可以发送一个消息，用于处理响应手势动作后的任务。当然，不同的手势识别器，发送的消息方法也会有所不同。

1. [代码]一个手指，拍击两次手势

01// 创建一个手势识别器
02UITapGestureRecognizer *oneFingerTwoTaps =
03  [[[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(oneFingerTwoTaps)] autorelease];
04  
05// Set required taps and number of touches
06[oneFingerTwoTaps setNumberOfTapsRequired:2];
07[oneFingerTwoTaps setNumberOfTouchesRequired:1];
08  
09// Add the gesture to the view
10[[self view] addGestureRecognizer:oneFingerTwoTaps];
11 
12消息方法oneFingerTwoTaps
13- (void)oneFingerTwoTaps
14{
15  NSLog(@"Action: One finger, two taps");
16}

2. [代码]两个手指，拍击两次手势

01UITapGestureRecognizer *twoFingersTwoTaps =
02  [[[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(twoFingersTwoTaps)] autorelease];
03[twoFingersTwoTaps setNumberOfTapsRequired:2];
04[twoFingersTwoTaps setNumberOfTouchesRequired:2];
05[[self view] addGestureRecognizer:twoFingersTwoTaps];
06 
07消息方法twoFingersTwoTaps
08- (void)twoFingersTwoTaps {
09  NSLog(@"Action: Two fingers, two taps");
10}

3. [代码]一个手指向上、向下擦碰手势

01// 向上擦碰
02UISwipeGestureRecognizer *oneFingerSwipeUp =
03  [[[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(oneFingerSwipeUp:)] autorelease];
04[oneFingerSwipeUp setDirection:UISwipeGestureRecognizerDirectionUp];
05[[self view] addGestureRecognizer:oneFingerSwipeUp];
06 
07- (void)oneFingerSwipeUp:(UISwipeGestureRecognizer *)recognizer
08{
09  CGPoint point = [recognizer locationInView:[self view]];
10  NSLog(@"Swipe up - start location: %f,%f", point.x, point.y);
11}
12 
13// 向下擦碰
14UISwipeGestureRecognizer *oneFingerSwipeDown =
15  [[[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(oneFingerSwipeDown:)] autorelease];
16[oneFingerSwipeDown setDirection:UISwipeGestureRecognizerDirectionDown];
17[[self view] addGestureRecognizer:oneFingerSwipeDown];
18 
19- (void)oneFingerSwipeDown:(UISwipeGestureRecognizer *)recognizer
20{
21  CGPoint point = [recognizer locationInView:[self view]];
22  NSLog(@"Swipe down - start location: %f,%f", point.x, point.y);
23}

4. [代码]旋转手势

1UIRotationGestureRecognizer *twoFingersRotate =
2  [[[UIRotationGestureRecognizer alloc] initWithTarget:self action:@selector(twoFingersRotate:)] autorelease];
3[[self view] addGestureRecognizer:twoFingersRotate];
4 
5- (void)twoFingersRotate:(UIRotationGestureRecognizer *)recognizer
6{
7  // Convert the radian value to show the degree of rotation
8  NSLog(@"Rotation in degrees since last change: %f", [recognizer rotation] * (180 / M_PI));
9}

5. [代码]向里或向外捏的手势跳至 [1] [2] [3] [4] [5] [全屏预览]

view source
print?
1UIPinchGestureRecognizer *twoFingerPinch =
2  [[[UIPinchGestureRecognizer alloc] initWithTarget:self action:@selector(twoFingerPinch:)] autorelease];
3[[self view] addGestureRecognizer:twoFingerPinch];
4 
5- (void)twoFingerPinch:(UIPinchGestureRecognizer *)recognizer
6{
7  NSLog(@"Pinch scale: %f", recognizer.scale);
8}