IOS 开发之触摸事件详细介绍

- (void)touchesBegan:(NSSet )touches withEvent:(UIEvent )event; 
- (void)touchesMoved:(NSSet )touches withEvent:(UIEvent )event; 
- (void)touchesEnded:(NSSet )touches withEvent:(UIEvent )event; 
- (void)touchesCancelled:(NSSet )touches withEvent:(UIEvent )event;

- (void)motionBegan:(UIEventSubtype)motion withEvent:(UIEvent *)event; 
- (void)motionEnded:(UIEventSubtype)motion withEvent:(UIEvent *)event; 
- (void)motionCancelled:(UIEventSubtype)motion withEvent:(UIEvent *)event;

- (void)remoteControlReceivedWithEvent:(UIEvent *)event;

- (void)touchesBegan:(NSSet )touches withEvent:(UIEvent )event

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

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

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

触摸产生时所处的窗口
@property(nonatomic,readonly,retain) UIWindow *window;
触摸产生时所处的视图
@property(nonatomic,readonly,retain) UIView  *view;
短时间内点按屏幕的次数，可以根据tapCount判断单击、双击或更多的点击
@property(nonatomic,readonly) NSUInteger tapCount;
记录了触摸事件产生或变化时的时间，单位是秒
@property(nonatomic,readonly) NSTimeInterval  timestamp;
当前触摸事件所处的状态
@property(nonatomic,readonly) UITouchPhase phase;

- (CGPoint)locationInView:(UIView *)view;
返回值表示触摸在view上的位置
这里返回的位置是针对view的坐标系的（以view的左上角为原点(0, 0)）
调用时传入的view参数为nil的话，返回的是触摸点在UIWindow的位置
- (CGPoint)previousLocationInView:(UIView *)view;
该方法记录了前一个触摸点的位置

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

 //取得UITouch对象
 UITouch *touch = [touches anyObject];
 //获取上一个点
 CGPoint p = [touch previousLocationInView:self];
 //获取当前点
 CGPoint currp = [touch locationInView:self];
 //产生平移拖拽效果
 self.transform = CGAffineTransformTranslate(self.transform, currp.x - p.x, currp.y - p.y);

}

private int x, y;
@Override
 public boolean onTouchEvent(MotionEvent event) {
  switch (event.getAction()){
   case MotionEvent.ACTION_DOWN:
    x = (int) event.getRawX();
    y = (int) event.getRawY();
    break;
   case MotionEvent.ACTION_MOVE:
    int mx = (int)event.getRawX();
    int my = (int)event.getRawY();

//    setTranslationX(getTranslationX()+mx-x);
//    setTranslationY(getTranslationY()+my-y);

    layout(getLeft()+mx-x,getTop()+my-y,getLeft()+getMeasuredWidth()+mx-x,getTop()+getMeasuredHeight()+my-y);

    x = mx;
    y = my;
    break;
  }
  return true;
 }

UIGestureRecognizer

UIGestureRecognizer是一个抽象类，定义了所有手势的基本行为，使用它的子类才能处理具体的手势
UITapGestureRecognizer(敲击)
UIPinchGestureRecognizer(捏合，用于缩放)
UIPanGestureRecognizer(拖拽)
UISwipeGestureRecognizer(轻扫)
UIRotationGestureRecognizer(旋转)
UILongPressGestureRecognizer(长按)

//创建手势识别器对象
UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] init];
//设置手势识别器对象的具体属性
// 连续敲击2次
tap.numberOfTapsRequired = 2;
// 需要2根手指一起敲击
tap.numberOfTouchesRequired = 2;
//添加手势识别器到对应的view上
[self.iconView addGestureRecognizer:tap];
监听手势的触发
[tap addTarget:self action:@selector(tapIconView:)];

//页面加载完成时调用
- (void)viewDidLoad {
 [super viewDidLoad];
 //创建手势识别器对象
  UIPanGestureRecognizer *pan = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(pan:)];
 //添加手势识别器到对应的view上
 [self.imageView addGestureRecognizer:pan];
}

- (void)pan:(UIPanGestureRecognizer *)pan
{
 // 获取手势的触摸点
 // CGPoint curP = [pan locationInView:self.imageView];

 // 获取手势的移动，也是相对于最开始的位置
 CGPoint transP = [pan translationInView:self.imageView];

 self.imageView.transform = CGAffineTransformTranslate(self.imageView.transform, transP.x, transP.y);

 // 复位
 [pan setTranslation:CGPointZero inView:self.imageView];
 //判断当前手指状态
 //if (pan.state == UIGestureRecognizerStateBegan) {//手指按下时类似于Android中的ACTION_DOWN
 //}
}

// 没有触摸事件发生，所有手势识别的默认状态
 UIGestureRecognizerStatePossible,
 // 一个手势已经开始但尚未改变或者完成时
 UIGestureRecognizerStateBegan,
 // 手势状态改变
 UIGestureRecognizerStateChanged,
 // 手势完成
 UIGestureRecognizerStateEnded,
 // 手势取消，恢复至Possible状态
 UIGestureRecognizerStateCancelled, 
 // 手势失败，恢复至Possible状态
 UIGestureRecognizerStateFailed,
 // 识别到手势识别
 UIGestureRecognizerStateRecognized = UIGestureRecognizerStateEnded 

#pragma mark - 手势代理方法
// 是否允许开始触发手势
//- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer
//{
// return NO;
//}

// 是否允许同时支持多个手势，默认是不支持多个手势
// 返回yes表示支持多个手势
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer
{
 return YES;
}

// 是否允许接收手指的触摸点
//- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch{
// // 获取当前的触摸点
// CGPoint curP = [touch locationInView:self.imageView];
//  return YES;
//}

// 事件传递的时候调用
// 当事件传递给控件的时候，就会调用控件的这个方法，寻找最合适的view
// point：当前的触摸点，point这个点的坐标系就是方法调用者
- (UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event
{
 // 调用系统的做法去寻找最合适的view，返回最合适的view
 UIView *fitView = [super hitTest:point withEvent:event];

// NSLog(@"fitView--%@",fitView);
 return fitView;
}

// 作用：判断当前这个点在不在方法调用者（控件）上
- (BOOL)pointInside:(CGPoint)point withEvent:(UIEvent *)event
{
 return YES;
}

- (UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event
{

 // 1.判断当前控件能否接收事件
 if (self.userInteractionEnabled == NO || self.hidden == YES || self.alpha <= 0.01) return nil;

 // 2. 判断点在不在当前控件
 if ([self pointInside:point withEvent:event] == NO) return nil;

 // 3.从后往前遍历自己的子控件
 NSInteger count = self.subviews.count;

 for (NSInteger i = count - 1; i >= 0; i--) {
  UIView *childView = self.subviews[i];

  // 把当前控件上的坐标系转换成子控件上的坐标系
  CGPoint childP = [self convertPoint:point toView:childView];

  UIView *fitView = [childView hitTest:childP withEvent:event];


  if (fitView) { // 寻找到最合适的view
   return fitView;
  }
 }
 // 循环结束,表示没有比自己更合适的view
 return self;
}