同步放大兩個UIScrollViews。

Question

我有兩個UIScrollViews。這兩個滾動視圖都包含一個圖像。現在，我想以編程方式縮放第二個滾動視圖，如果我手動放大第一個滾動視圖。我正在使用 - （UIView *）viewForZoomingInScrollView：（UIScrollView *）scrollView方法手動縮放第一個滾動視圖。第二個滾動視圖應放大到相同的點和縮放比例。我怎樣才能做到這一點？

Answer 1

嘗試像這樣在UIScrollViewDelegate方法：

override func scrollViewDidScroll(scrollView: UIScrollView){ 
    otherScrollView.contentOffset = scrollView.contentOffset 
    otherScrollView.zoomScale = scrollView.contentOffset 
} 

Answer 2

通過使用這兩個scrollviews的標籤或物體可以識別哪些滾動查看您需要放大viewForZoomingInScrollView方法。

e.g

//need to set the tag for scrollviews 
-(UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView 
{ 
if(scrollView.tag == 1) 
{ 
    return firstImageView; 
} 
return secondImageView; 

} 

OR 

//need to create the object of used scrollviews 
-(UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView 
{ 
if(scrollView == objScrollViewFirst) 

{ 
    return firstImageView; 
} 
return secondImageView; 

} 

Answer 3

怎麼是這樣的：

CGRect zoomRect; 
zoomRect.size.height = manualScrollView.frame.size.height/manualScrollView.zoomScale; 
zoomRect.size.width = manualScrollView.frame.size.width/manualScrollView.zoomScale; 
zoomRect.origin.x = manualScrollView.center.x - (zoomRect.size.width/2.0); 
zoomRect.origin.y = manualScrollView.center.y - (zoomRect.size.height/2.0); 

[autoScrollView zoomToRect:zoomRect animated:YES]; 
[autoScrollView setZoomScale:manualScrollView.zoomScale animated:YES];