縮放自定義的UIView打破了touchesMoved

Question

拖着我已經準備和檢查到GitHub的a simple test case用於拖動定製UIView：

它運作良好，並拖動中實現的Tile.m爲：

- (void) touchesMoved:(NSSet*)touches withEvent:(UIEvent*)event 
{ 
    UITouch *touch = [touches anyObject]; 
    CGPoint location = [touch locationInView:self]; 
    CGPoint previous = [touch previousLocationInView:self]; 
    self.frame = CGRectOffset(self.frame, 
           (location.x - previous.x), 
           (location.y - previous.y)); 
} 

然而，瓷磚太大，my actual game（我將不得不調整它們的縮放比例，一旦遊戲板在UIScrollView無論如何放大）：

所以我擴展我的自定義UIView s下降致電

tile.transform = CGAffineTransformMakeScale(.5, .5); 

大小的變化，但由於所需的瓷磚突然拖「的兩倍快」：

也許touchesMoved代碼（一個或多個。上面）應該調整，但我不確定那裏的操作是由什麼打破的？

Answer 1

沒關係，我已經找到了解決辦法：

- (void) touchesMoved:(NSSet*)touches withEvent:(UIEvent*)event 
{ 
    UITouch *touch = [touches anyObject]; 
    CGPoint location = [touch locationInView:self]; 
    CGPoint previous = [touch previousLocationInView:self]; 

    if (!CGAffineTransformIsIdentity(self.transform)) { 
     location = CGPointApplyAffineTransform(location, self.transform); 
     previous = CGPointApplyAffineTransform(previous, self.transform); 
    } 

    self.frame = CGRectOffset(self.frame, 
           (location.x - previous.x), 
           (location.y - previous.y)); 
}