触摸事件以及手势

由于博主本人比较懒，学习过程中也做了印象笔记，所以以后博客的内容将直接复制印象笔记中的内容，排版会有些奇怪，博主一般做笔记的习惯是直接在XCode上直接打然后截图在印象笔记上所以会有很多图片，以后博客内容每周更新整理一次，会尽力将博主这礼拜所学东西都上传的。

手势简单来说就是我们创建一个手势然后由UIView来添加，这样子UIView就可以根据你的手势来执行手势的方法，具体的来看代码实现

点按

UITapGestureRecognizer *aTap=[[UITapGestureRecognizer alloc]initWithTarget:self action:@selector(changeColor;)];
aTap.numberOfTapsRequired=2;//点击若干次数才执行事件
aTap.numberOfTouchesRequired=2;//点击的手指数
[self .view addGestureRecognizer:aTap];//让self.view 添加了这个事件之后这个视图只要点击了点按就要实现changecolor得事件

长按

UILongPressGestureRecognizer *aLong=[[UILongPressGestureRecognizer alloc]initWithTarget:self action :@selector(执行事件:)];
aLong.minimumPressDuration=2;//至少长按2秒
aLong.allowableMovement=50;//在出发手势之前，手指可以移动的范围（在这个范围内，依然可以出发长按事件）
[self.view addGestureRecognizer: aLong];

轻扫

UISwipeGestureRecognizer *aSwipe=[[UISwipeGestureRecognizer alloc]initWithTargrt:self action:selector( 执行事件：)];
aSwipe.direction=UISwipeGestureRecognizerDirectionleft|UISwipeGestureRecognizerDirectionRight;//轻扫左边或者右边，注意不能同时有轻扫左右和上下 也就是说不能既有扫左又扫上
self.view addGestureRecognizer:aSwipe];

捏合

UIPinchGestureRecognizer *aPinch = [[UIPinchGestureRecognizer alloc]initWithTarget:self action:@selector(pinchImageView:)];//最后不要忘了还要添加
旋转

    UIRotationGestureRecognizer *aRotate = [[UIRotationGestureRecognizer alloc]initWithTarget:self action:@selector(rotateImageView:)];
拖拽

 UIPanGestureRecognizer *aPan = [[UIPanGestureRecognizer alloc]initWithTarget:self action:@selector(panImageView:)];
    [self.imageView addGestureRecognizer:aPan];

手势也有代理方法

@interface ViewController ()<UIGestureRecognizerDelegate>

//某一块区域点击
-(BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch
/**
 *  是否允许多个手势事件执行
 */
-(BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer

清除手势

 self.view removeGestureRecognizer:<#(nonnull UIGestureRecognizer *)#>

如果一个view 添加了多个手势，要一个个的清除，他们在View里面是以数组的形式，如博主的某个例子

-(void)removeGR
{
    for (UIGestureRecognizer *gestureR in self.imageView.gestureRecognizers) {
        [self.imageView removeGestureRecognizer:gestureR];
        
    }
}

触摸事件

-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
    //获取点击屏幕时的touch对象
    UITouch *touch = [touches anyObject];
    CGPoint point = [touch locationInView:touch.view];//这2步就可以得到触摸的这个点

-(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{

-(void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
-(void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event