Gesture-Pinch（捏）

1。Pinch works in two ways:scaling up / scaling down ，连续的手势

@property (nonatomic, strong) UILabel *lbl;

@property  CGFloat currentScale; //比例

- (void) handlePinches:(UIPinchGestureRecognizer*)paramSender{

    

    if (paramSender.state == UIGestureRecognizerStateEnded){

        self.currentScale = paramSender.scale;

    } else if (paramSender.state == UIGestureRecognizerStateBegan &&

               self.currentScale != 0.0f){

        paramSender.scale = self.currentScale;

    }

    

    if (paramSender.scale != NAN && paramSender.scale != 0.0){

        paramSender.view.transform = CGAffineTransformMakeScale(paramSender.scale,  paramSender.scale); // X , Y

    }  

}

-(void)initLabel {

    CGRect labelRect = CGRectMake(0.0f, 0.0f,200.0f,200.0f); 

    

    self.lbl = [[UILabel alloc] initWithFrame:labelRect];

    self.lbl.center = self.view.center;

    self.lbl.backgroundColor = [UIColor greenColor ] ;

     //可交互，通常在图像上操作也需要加，如UIImageView ...

    self.lbl.userInteractionEnabled = YES;

    

    [self.view addSubview:self.myBlackLabel];

}

- (void)addGesture {

    UIPinchGestureRecognizer *pinchGesture =  [[UIPinchGestureRecognizer alloc] initWithTarget:self action:@selector(handlePinches:)];

    //在UILabel上加手势

    [self.lbl addGestureRecognizer:self.pinchGestureRecognizer];   

}