关于Iphone的手势识别
??以前說過一些關于Iphone手勢識別的內容,但是沒有具體的寫些相關的內容,今天就用手勢識別中的兩種來簡單講講
??一、我們先說說兩個手指的縮放操作:UIPinchGestureRecognizer
1、在viewDidLoad中初始化UIPinchGestureRecognizer對象,并通過view的addGestureRecognizer方法將它添加到view上:
- (void)viewDidLoad {[self CreateButton];//pinchUIPinchGestureRecognizer *pinchGesture = [[UIPinchGestureRecognizer alloc]initWithTarget:selfaction:@selector(pinchGestureHandler:)];[m_svImageView addGestureRecognizer: pinchGesture];[pinchGesture release];[super viewDidLoad];2、完成其中的action的內容,根據sender的scale來判斷是放大還是縮小;
3、之后便根據UIGetsureRecognizerStateEnded來判斷手是否離開屏幕,并根據sender的scale來判斷是放大還是縮小并將最后的scale值保存到lastScaleView中:
- (IBAction) pinchGestureHandler:(UIGestureRecognizer *)sender {lastScaleValue = 1;CGFloat scalevalue = [(UIPinchGestureRecognizer *)sender scale];if (scalevalue >1) {sender.view.transform = CGAffineTransformMakeScale(lastScaleValue + scalevalue, lastScaleValue + scalevalue);}else {sender.view.transform = CGAffineTransformMakeScale(lastScaleValue * scalevalue, lastScaleValue * scalevalue);}if(sender.state == UIGestureRecognizerStateEnded){if (scalevalue > 1) {lastScaleValue += scalevalue;}else {lastScaleValue *= scalevalue;}}}4、完成!
5、小常識:在iOS Simulator中,按住Option鍵拖動鼠標可實現兩個手指的觸摸;?
??二、我們再說說長按手指的操作:UILongPressGestureRecognizer
1、和兩個手指操作類似,長按手指同樣需要在viewDidLoad中對UILongPressGestureRecognizer的對象進行初始化。
2、需要注意的是,我們還需要設置好UILongPressGestureRecognizer對象的長按最短時間、長按時可移動的像素范圍、以及長按手指的個數,之后同樣通過view的addGestureRecognizer方法將它添加到view中:
- (void)viewDidLoad {UILongPressGestureRecognizer *longpressGesture = [[UILongPressGestureRecognizer alloc]initWithTarget:selfaction:@selector(longpressGestureHandler:)];longpressGesture.minimumPressDuration = 1;longpressGesture.allowableMovement = 15;longpressGesture.numberOfTouchesRequired = 1;[m_svImageView addGestureRecognizer:longpressGesture];[longpressGesture release];[super viewDidLoad];}3、之后同樣時完成action的內容,可以使用if(sender.state == UIGestureRecognizerStateBegan)來判斷何時觸發長按操作:
- (IBAction) longpressGestureHandler: (UILongPressGestureRecognizer *) sender {if([(UILongPressGestureRecognizer *)sender state] == UIGestureRecognizerStateBegan){m_imageView.image = m_uiImage;} }4、完成!
??三、附6種常用手勢:
UITapGestureRecognizer
UIPinchGestureRecognizer
UIRotationGestureRecognizer
UIPanGestureRecognizer
UISwipeGestureRecognizer
UILongPressGestureRecognizer
總結
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