我怎樣才能抓住MapView，然後將它傳遞給默認的手勢識別器？

Question

這是我想要的 - 用戶在地圖上點擊，我的代碼被執行，然後系統代碼被執行（如果用戶點擊註釋標註出現等）。

我添加簡單的點擊識別到地圖視圖：

UITapGestureRecognizer *tapGestureRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(mapViewTapped:)]; 
[self.mapView addGestureRecognizer:tapGestureRecognizer]; 
[tapGestureRecognizer release]; 

裏面mapViewTapped我的代碼被執行。現在我想通知系統的點擊代碼（例如顯示標註）。我怎麼做？如何傳遞我攔截的事件？

Answer 1

的方法之一是實現UIGestureRecognizerDelegate方法gestureRecognizer:shouldRecognizeSimultaneouslyWithGestureRecognizer:並在它返回YES：

//add <UIGestureRecognizerDelegate> to .h to avoid compiler warning 

//add this where you create tapGestureRecognizer... 
tapGestureRecognizer.delegate = self; 

-(BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer 
    shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer 
{ 
    return YES; 
} 

現在你mapViewTapped:將被調用，然後在地圖視圖的識別器將調用它的方法。如果點擊位於註釋視圖上，則地圖視圖將顯示其標註（如果已實施，則會調用didSelectAnnotationView委託方法）。

另一種方式，如果你需要更多的控制，那麼不要做上述情況，在你mapViewTapped:您可以檢查是否水龍頭是在一個註解視圖，然後手動選擇註釋然後將展示其標註（和調用didSelectAnnotationView委託方法）：

-(void)mapViewTapped:(UITapGestureRecognizer *)tgr 
{ 
    CGPoint p = [tgr locationInView:mapView]; 

    UIView *v = [mapView hitTest:p withEvent:nil]; 

    id<MKAnnotation> ann = nil; 

    if ([v isKindOfClass:[MKAnnotationView class]]) 
    { 
     //annotation view was tapped, select it... 
     ann = ((MKAnnotationView *)v).annotation; 
     [mapView selectAnnotation:ann animated:YES]; 
    } 
    else 
    { 
     //annotation view was not tapped, deselect if some ann is selected... 
     if (mapView.selectedAnnotations.count != 0) 
     { 
      ann = [mapView.selectedAnnotations objectAtIndex:0]; 
      [mapView deselectAnnotation:ann animated:YES]; 
     } 
    } 
}