iOS手勢識別的簡單應用

六種手勢

1.手勢分類

• UITapGestureRecognizer(敲擊)
• 設置numberOfTapsRequired點擊的次數
• 結合代理(BOOL) gestureRecognizer能夠選定可點擊的區域
• UIPinchGestureRecognizer(捏合，用於縮放)
• 注意復位問題
• UIPanGestureRecognizer(拖拽)
• UISwipeGestureRecognizer(輕掃)
• UIRotationGestureRecognizer(旋轉)
• UILongPressGestureRecognizer(長按)
  • 長按的兩次響應問題的解決

2.對每個手勢的注意點及代碼實現進行說明

• UITapGestureRecognizer(敲擊)

  #pragma mark - tap敲擊
  /**
   *  1.numberOfTapsRequired設置點擊幾回響應
   *  2.代理與(BOOL) gestureRecognizer結合，可肯定圖片哪一個區域能夠點，哪些不能點
   */
  -(void) setTap{
      //建立點按手勢
      //initWithTarget:誰監聽這個事件呢，通常控制器
      UITapGestureRecognizer *tap=[[UITapGestureRecognizer alloc]initWithTarget:self action:@selector(tap:)];
      //delegate
      tap.delegate=self;
      //click counts
      tap.numberOfTapsRequired=2;
      //添加手勢，用的是多態addGestureRecognizer:(UIGestureRecognizer*)gestureRecognizer（父類）
      [self.imageView addGestureRecognizer:tap];
  }
  
  -(void) tap:(UITapGestureRecognizer *) tap{
      NSLog(@"%s",__func__);
  }

#pragma mark - UIGestureRecognizerDelegate //與tap結合 -(BOOL) gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldReceiveTouch:(UITouch )touch{ //獲取當前觸摸點在self.imageView的哪一個位置 CGPoint curP=[touch locationInView:self.imageView]; if (curP.x<self.imageView.bounds.size.width0.5) { return YES; }else{ return NO; } }

```

• UIPinchGestureRecognizer(捏合，用於縮放)

#pragma mark - pinch捏合，用於縮放 -(void) setPinch{ UIPinchGestureRecognizer *pinch=[[UIPinchGestureRecognizer alloc]initWithTarget:self action:@selector(pinch:)]; pinch.delegate=self; [self.imageView addGestureRecognizer:pinch]; } -(void) pinch:(UIPinchGestureRecognizer *) pinch{ NSLog(@"%s",func); self.imageView.transform=CGAffineTransformScale(self.imageView.transform, pinch.scale, pinch.scale); pinch.scale=1; } ```

• UIPanGestureRecognizer(拖拽)

  #pragma mark - pan拖拽
  /**
   *  復位是指返回到起始的狀態，再能過相對上一個狀態tansform來解決一些問題
   */
  -(void) setPan{
      UIPanGestureRecognizer *pan=[[UIPanGestureRecognizer alloc]initWithTarget:self action:@selector(pan:)];
  
      [self.imageView addGestureRecognizer:pan];
  }
  
  -(void) pan:(UIPanGestureRecognizer *) pan{
      NSLog(@"%s",__func__);
  //    CGPoint curP=[pan locationInView:self.imageView];
      //獲取圖片移動距離
      CGPoint curP=[pan translationInView:self.imageView];
      self.imageView.transform=CGAffineTransformTranslate(self.imageView.transform, curP.x, curP.y);
      //復位
      [pan setTranslation:CGPointZero inView:self.imageView];
  }

• UISwipeGestureRecognizer(輕掃)

  #pragma mark - swipe輕掃
  -(void) setSwipe{
      //添加向左滑動
      UISwipeGestureRecognizer *swipe=[[UISwipeGestureRecognizer alloc]initWithTarget:self action:@selector(swipe:)];
      swipe.direction=UISwipeGestureRecognizerDirectionLeft;
      [self.imageView addGestureRecognizer:swipe];
      //添加向右滑動
      UISwipeGestureRecognizer *swipeDown=[[UISwipeGestureRecognizer alloc]initWithTarget:self action:@selector(swipe:)];
      swipeDown.direction=UISwipeGestureRecognizerDirectionRight;
      [self.imageView addGestureRecognizer:swipeDown];
  
  }
  -(void) swipe:(UISwipeGestureRecognizer *)swipe{
      NSLog(@"%s",__func__);
  }

• UIRotationGestureRecognizer(旋轉)

  #pragma mark - rotation旋轉
  -(void) setRotation{
      UIRotationGestureRecognizer *rotation=[[UIRotationGestureRecognizer alloc]initWithTarget:self action:@selector(rotation:)];
      rotation.delegate=self;
      [self.imageView addGestureRecognizer:rotation];
  }
  -(void) rotation:(UIRotationGestureRecognizer *) rotation{
      NSLog(@"%s",__func__);
      NSLog(@"%f",rotation.rotation);
      self.imageView.transform=CGAffineTransformRotate(self.imageView.transform, rotation.rotation);
      [rotation setRotation:0];
  //    rotation.rotation=0;
  
  }

• UILongPressGestureRecognizer(長按)

  #pragma mark - longPress長按
  -(void) setLongPress{
      UILongPressGestureRecognizer *longPress=[[UILongPressGestureRecognizer alloc]initWithTarget:self action:@selector(longPress:)];
      [self.imageView addGestureRecognizer:longPress];
  }
  /**
   *  長按的一些注意點，那就是長按時觸發一次，離開時再觸發一次
   *  加個判斷，結束與開始選一個觸發的時間
   *  @param longPress 傳參
   */
  -(void) longPress:(UILongPressGestureRecognizer *) longPress{
      if (longPress.state==UIGestureRecognizerStateBegan) {
          NSLog(@"%s",__func__);
      }
  
  }

• 當同時多個手勢能夠處理時(代理)

/**

• 是否支持多個手勢同時處理
• @param gestureRecognizer 。。
• @param otherGestureRecognizer 。。
• @return return value bool */ -(BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer{ return YES; }

3.源代碼的地址

• github地址