如何使對象可拖動？

Question

嘿傢伙我想知道是否有遠離使UIImageView可拖動的對象。我知道的UITouch和觸摸即

-(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event 
{ 
    UITouch *drag=[[event allTouches] anyObject]; 
    player.center=[drag locationInView:self.view]; 
} 

，但以這種方式，可以爲用戶進行跨屏幕中的對象跳轉到他或她觸摸屏，但我希望用戶必須手動在屏幕上拖動對象。

請及時與代碼解釋，讓我知道，如果我必須要更具體的或透明......

Answer 1

你可以這樣做：

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

    UITouch *aTouch = [touches anyObject]; 
    CGPoint location = [aTouch locationInView:self.view]; 

    if(CGRectContainsPoint(self.playerView.frame,location)) { 
     [UIView beginAnimations:@"Dragging A DraggableView" context:nil]; 
     self.playerView.center = location; 
     [UIView commitAnimations]; 
    } 

} 

這應該給你一個平滑的動畫。

Answer 2

，如果你希望你的用戶拖動&下降，首先你要檢查觸摸是ImageView的內矩形框架。爲了改善用戶體驗，您可以檢測來自imageview中心的觸摸偏移;一個好的地方是在the touchesBegan:withEvent:之內。在這之後，你必須改變的ImageView的位置，就像這樣：

CGPoint touchOffset; //insert this inside your interface private iVars 
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event { 
    UITouch *drag=[[event allTouches] anyObject]; 
    CGPoint touchLocation = [drag locationInView:self.view]; 
    touchOffset = CGPointMake(player.center.x-touchLocation.x,player.center.y-touchLocation.y) 
    if(CGRectContainsPoint(player.frame,touchLocation) 
     player.center = CGPointMake(touchLocation.x+touchOffset.x,touchLocation.y+touchOffset.y); 
} 
-(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event 
{ 
    UITouch *drag=[[event allTouches] anyObject]; 
    CGPoint touchLocation = [drag locationInView:self.view]; 
    if(CGRectContainsPoint(player.frame,touchLocation) 
     player.center = CGPointMake(touchLocation.x+touchOffset.x,touchLocation.y+touchOffset.y); 
} 

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Answer 3

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

    UITouch* aTouch = [touches anyObject]; 
    UIView* aView = [aTouch view]; 
    if (aView != self.view) { 
     [self.view bringSubviewToFront:aView]; 
    } 
} 

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

    UITouch* aTouch = [touches anyObject]; 
    UIView* aView = [aTouch view]; 
    if (aView != self.view) { 
     aView.center = [aTouch locationInView:self.view]; 

    } 
}