本節學習內容
1.UIGesture擴展手勢類型
2.UIGesture擴展手勢屬性
3.UIGesture擴展手勢用法
UIGesture擴展手勢
【UIPan手勢】
平移手勢：可以用手指在屏幕上移動的手勢
【UISwipe手勢】
滑動手勢：左滑，右滑，上滑，下滑
【UILongPress手勢】
長按手勢：長時間按住一個試圖響應事件
【重點屬性函數】
minimumPressDuration:長按時間長充
direction:滑動手勢方向
UIGestureRecognizerStateBegan:長按時間狀態
translationInView:獲取平移手勢位置
velocityInView:獲取平移手勢的速度
【ViewController.m】
UIImageView* iView=[[UIImageView alloc]initWithImage:[UIImage imageNamed:@"17_2.jpg"]];
iView.frame=CGRectMake(50,50,200,300);
iView.userInteractionEnabled=YES;
//創建一個平易手勢，參數1：事件函數處理對象，參數2：事件函數
UIPanGestureRecognizer* pan=[[UIPanGestureRecognizer alloc]initWithTarget:self action:@selector(panAct:)];
//將手勢添加到圖像視圖中
[iView addGestureRecognizer:pan];
//將移動事件手勢從圖像中取消
[iView removeGestureRecognizer:pan];
[self.view addSubview:iView];
｝
//移動事件函數，只要手指坐標在屏幕上發生變化時，函數就被調用
-(void)panAct:(UIPanGestureRecognizer*)pan{
//獲取移動的從標，現對于視圖的坐標系統，參數：相對的視圖對象
CGPoint pt=[pan translationInView:self.view];
//打印移動坐標位置
//NSLog(@“pt.x=%f,pt.y=%f”,pt.x,pt.y);
//獲取移動時的相對速度
CGPoint pv=[pan velocityInView:self.view];
NSLog(@“pv.x=%.2f,pv.y=%.2f”,pt.x,pt.y);
//創建一個滑動手勢
UISwipeGestureRecognizer* swipe=[[UISwipeGestureRecognizer allock]initWithTarget:self action:@selector(swipeAct:)];
//設定滑動手勢接受事件的類型，UISwipeGestureRecognizerDirectionLeft：向械滑動，UISwipeGestureRecognizerDirectionRight:向左滑動，UISwipeGestureRecognizerDirectionUp：向上滑動,UISwipeGestureRecognizerDirectionDown:向下滑動
//用‘|‘表示支持多個事件，或的關系
swipe.direction=UISwipeGestureRecognizerDirectionLeft |UISwipeGestureRecognizerDirectionRight;
[iView addGestureRecognizer:swipe];
//創建長按手勢
UILongPressGestureRecgnizer* longPress=[UILongPressGestureRecognizer alloc]initWithTarget:self acion:@selector(pressLong:)];
//設置長按手勢時間，默認0.5秒時間長按手勢
longPress.minimumPressDuration=0.5;
}
-(void)pressLong:(UILongPressGestureRecognizer*)press{
//手勢的狀態對象，到達規定時間，秒釧觸發函數
if(press.state==UIGestureRecognizerStateBegan){
NSLog(@"狀態開始！");
}
//當手指離開屏幕時，結束狀態
else if(press.state==UIGestureRecognizerStateEended){
NSLog(@"結束狀態！");
}
NSLog(@"長按手勢！");
}
//指有向指定方滑動才執行
-(void)swipeAct(UISwipeGestureRecognizer*) swipe{
if(swipe.direction & UISwipeGestureRecognizerDirectionLeft){
NSLog(@"向左滑動！");
}else if(swipe.direction & UISwipeGestureRecognizerDirectionRight){
NSLog(@"向右滑動！");
}
}
