如何使用帶有fromRect的UIPopoverController

Question

任何人都可以告訴我rect和view應該是什麼？我不明白我將傳遞給選擇器。一個例子會很棒！

http://developer.apple.com/library/ios/#documentation/uikit/reference/UIPopoverController_class/Reference/Reference.html

- (void)presentPopoverFromRect:(CGRect)rect inView:(UIView *)view permittedArrowDirections:(UIPopoverArrowDirection)arrowDirections animated:(BOOL)animated 

Answer 1

我用這個很頻繁。假設你想要點擊一張圖片並展示一個關於它的信息。假設你有你的圖像上的選擇方法(handleImageTap:)一個手勢識別，這裏將是一個示例代碼來實現這一目標：

- (void)handleImageTap:(UIGestureRecognizer *)gesture { 
    // initialize your popover view controller and assign it to your popoverController 
    MyPopoverViewController *content = [[MyPopoverViewController alloc] init]; 
    popoverController = [[UIPopoverController alloc] initWithContentViewController:content]; 
    popoverController.popoverContentSize = CGSizeMake(600, 600); 
    popoverController.delegate = self; 
    [content release]; 

    if (popoverController.popoverVisible == NO) { 
     // you can find the tappedImage through the gesture by searching up superviews if you don't already have a reference to it; 
     [popoverController presentPopoverFromRect:[tappedImage frame] inView:self.view 
     permittedArrowDirections:UIPopoverArrowDirectionAny animated:YES];     
    } 
    else { 
     [popoverController dismissPopoverAnimated:YES]; 
    } 
} 

所以基本上，view將self.view監守您從當前顯示它視圖控制器。 rect就是你想讓popover顯示的任何東西。在這種情況下，它被設置爲從圖像的框中顯示。我希望這可以幫助你。如果還有些問題，我會很樂意嘗試清除它