Touch:在与设备的多点触摸屏交互时生成。 响应者对象 响应者对象就是可以响应事件并对事件作出处理。在iOS中,存在UIResponder类,它定义了响应者对象的所有方法。UIApplication、UIView等类都继承了UIResponder类这些类的实例都可以当作响应者。 第一响应者 当前接受触摸的响应者对象被称为第一响应者,即表示当前该对象正在与用户交互,它是响应者链的开端。 响应者链 事件被交由第一响应者对象处理,如果第一响应者不处理,事件被沿着响应者链向上传递,交给下一个响应者。一般来说,第一响应者是个视图或控件,并且首先对事件进行响应,如果第一响应者不处理该事件,事件就会被传递给它的视图控制器,如果此视图控制器不处理该事件,则将事件传递给父视图,如果父视图没有响应,则该事件转到父视图控制器。 ,以此类推,直到顶层视图。接下来会沿着顶层视图到窗口(UIWindow对象)再到程序(UIApplication对象)。如果UIApplication不响应该事件,该事件逐渐进入睡眠状态。 当发生触摸时,会触发下列方法: touchesBegan:withEvent touchesMoved:withEvent touchesEnded:withEvent touchesCancelled:withEvent 在给定的触摸阶段中,如果发生新的触摸动作或已有的触摸动作发生变化,应用程序就会发送如下消息: 当一个或多个手指触碰屏幕时,发送touchesBegan:withEvent:消息。 当一个或多个手指在屏幕上移动时,发送touchesMoved:withEvent:消息。 当一个或多个手指离开屏幕时,发送touchesEnded:withEvent:消息。 当触摸序列被诸如电话呼入这样的系统事件所取消时,发送touchesCancelled:withEvent:消息。 以上方法都有两个参数。 第一个参数是一个UITouch对象的集合,表示给定阶段中 新的或者发生变化的触摸动作;第二个参数是一个UIEvent对象,表示这个特定的事件。 为了处理给定阶段的事件,响应者对象常常从传入的集合参数中取得一或多个UITouch对象,然后考察这些对象的属性或取得它们的位置. 1.如果需要处理所有触摸对象,可以向该NSSet对象发送anyObject消息。 2.UITouch实例的tapCount属性还可以给出发生多少次触碰 3.UITouch类中有一个名为locationInView:的重要方法,如果传入self参数值,它会给出触摸动作在响应者坐标系统中的位置 检测双击手势 - (void) touchesEnded:(NSSet*)touches withEvent:(UIEvent*)event { UITouch *touch = [touches anyObject]; if ([touch tapCount] == 2) { CGPoint tapPoint = [theTouch locationInView:self]; // Process a double-tap gesture } } 响应者类并不是必须实现上面列出的事件方法。举例来说,如果它只对手指离开屏幕感兴趣,则只需要实现touchesEnded:withEvent:方法就可以了。 UILabel *_messageLabel; @property(nonatomic, retain) UILabel *messageLabel; @synthesize messageLabel = _messageLabel; //创建messageLabel _messageLabel = [[UILabel alloc]initWithFrame:CGRectMake(20, 40, 280, 80)]; _messageLabel.backgroundColor = [UIColor clearColor]; _messageLabel.textAlignment = UITextAlignmentLeft; [self.view addSubview:messageLabel]; - (void)updateMessageLabelFromTouches:(NSSet *)touches touchStr:(NSString *)touchStr { int munTaps = [[touches anyobject] tapCount]; NSString *tapsMessage = [NSString stringWithFormat:@"%@,%d touches",touchStr,munTaps] _messageLabel.text = tapsMessage; } // 手指触碰屏幕时 - (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event { NSString *tmpStr = @"Touches Began"; [sele updateMessageLabelFromTouches:touches touchStr:tmpStr]; } // 手指在屏幕上移动时 - (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event; { NSString *tmpStr = @"Touches Moved"; [sele updateMessageLabelFromTouches:touches touchStr:tmpStr]; } // 手指离开屏幕时 - (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event; { NSString *tmpStr = @"Touches Ended"; [sele updateMessageLabelFromTouches:touches touchStr:tmpStr]; } // 当触摸序列被系统事件所取消时 - (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event { NSString *tmpStr = @"Touches Cancelled"; [sele updateMessageLabelFromTouches:touches touchStr:tmpStr]; } 2.手势:是指从你用一个或多个手指接触屏幕时开始,直到你的手指离开屏幕为止所发生的所有事件。 2.1.UITapGestureRecognizer敲击手势(单击和双击) 2.2.UIPanGestureRecognizer(拖动手势) 2.3.UIPinchGestureRecognizer(缩放手势) 2.4.UISwipeGestureRecognizer(滑动手势) 2.5.UIRotationGestureRecognizer(旋转手势) 2.6.UILongPressGestureRecognizer(长按手势) • 1.UITapGestureRecognizer敲击手势 UIView *_view _View = [[UIView alloc] initWithFrame:CGRectMake(10, 50, 300, 300)]; [_view setBackgroundColor:[UIColor redColor]]; // 单击的 Recognizer UITapGestureRecognizer *tapRecognizer= [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(tap:)]; //点击的次数 tapRecognizer.numberOfTapsRequired = 1; // 单击 tapRecognizer.numberOfTapsRequired = 2; // 双击 //点击的手指数 singleRecognizer.numberOfTouchesRequired = 1; //给view添加一个手势监测; [tapView addGestureRecognizer:singleRecognizer]; // 单击或双击后调用的方法 - (void) tap:(UITapGestureRecognizer *)sender { if (sender.numberOfTapsRequired == 1) { [_view setBackgroundColor:[UIColor greenColor]]; }else if(sender.numberOfTapsRequired == 2){ //双击 [_view setBackgroundColor:[UIColor yellowColor]]; } } 2.1UIPanGestureRecognizer(拖动手势) UIPanGestureRecognizer *panRecognizer = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(pan:)]; [_view addGestureRecognizer: panRecognizer]; -(void) pan:(UIPanGestureRecognizer *) pan { [_panView setBackgroundColor:[UIColor yellowColor]]; } 3.1UIPinchGestureRecognizer(缩放手势) UIPinchGestureRecognizer *pinchRecognizer = [[UIPinchGestureRecognizer alloc] initWithTarget:self action:@selector(pinch:)]; [_view addGestureRecognizer: *pinchRecognizer]; - (void)pinch:(UIPinchGestureRecognizer *)pinch { [_pinchView setBackgroundColor:[UIColor yellowColor]]; } 4.1 UISwipeGestureRecognizer 滑动手势 UISwipeGestureRecognizer *swipeRecognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(swipe:)]; //设置滑动方向 Down/Left/Right/Up swipeRecognizer.direction = UISwipeGestureRecognizerDirectionDown; [_view addGestureRecognizer:swipeRecognizer]; - (void)swipe:(UISwipeGestureRecognizer *)swipe { [_swipeView setBackgroundColor:[UIColor yellowColor]]; } 5.1UIRotationGestureRecognizer(旋转手势) UIRotationGestureRecognizer *rotation = [[UIRotationGestureRecognizer alloc] initWithTarget:self action:@selector(rotation:)] [_view addGestureRecognizer:rotation]; - (void) rotation:(UIRotationGestureRecognizer *)rotation { [_rotationView setBackgroundColor:[UIColor yellowColor]]; } 6.1 UILongPressGestureRecognizer长按手势 UILongPressGestureRecognizer *longPress = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(longPress:)]; [_longPressView addGestureRecognizer:longPress]; longPress.minimumPressDuration = 3.0; // 按3秒相应 [_view addGestureRecognizer:longPress]; - (void)longPress:(UILongPressGestureRecognizer *)longPress { [_longPressView setBackgroundColor:[UIColor yellowColor]]; }