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我目前正在为 iPad 优化应用程序，并希望使用带有图像的 UIBarButtonItem 来呈现弹出框。如果我使用带有标题的按钮，我目前拥有的代码效果很好，但我更喜欢使用我自己的图像或 UIBarButtonSystemItem 提供的图像之一。如果我根本不设置按钮的标题，它根本不会出现。如果我设置标题和图像，我会在真实硬件上获得标题，但图像会显示在模拟器上。使用 UIBarButtonSystemItem，我得到了我想要的按钮，但它也出现在横向模式下（它不应该这样做，因为我对横向使用了拆分视图）。

使用 setImage、setTitle 的任意组合或将按钮初始化为系统预设均无效。当检测到旋转到横向时，我还尝试将系统预设的按钮设置为 nil，但它仍保留在屏幕上。我不确定如何从这里开始，但我真的很想避免在这个按钮上使用字符串，而且我很想知道为什么会这样。

这是代码：

#pragma mark Split view handling
-(void)splitViewController:(UISplitViewController *)svc 
    willHideViewController:(UIViewController *)aViewController 
         withBarButtonItem:(UIBarButtonItem *)barButtonItem 
      forPopoverController:(UIPopoverController *)pc
{
    //If this bar button item doesn't have a title, it won't appear at all.
    [barButtonItem setTitle:@"-"];
    //barButtonItem = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemOrganize target:[barButtonItem target] action:[barButtonItem action]];
    [barButtonItem setImage:[UIImage imageNamed:@"listing.png"]];

    //Take this bar button item and put it on the left side of our nav item
    [[self navigationItem] setLeftBarButtonItem:barButtonItem];
    self.popoverController = pc;
}

-(void)splitViewController:(UISplitViewController *)svc 
    willShowViewController:(UIViewController *)aViewController 
 invalidatingBarButtonItem:(UIBarButtonItem *)barButtonItem
{
    //Remove the bar button item from our navigation item.
    //We'll double check that it's the correct button, even though we know it is.
    if(barButtonItem == [[self navigationItem] leftBarButtonItem]){
        [[self navigationItem] setLeftBarButtonItem:nil];
    }
    self.popoverController = nil;
}

更新：

我将此添加到我的 viewDidLoad 中：

customButtonItem = [[UIBarButtonItem alloc] initWithCustomView:[[UIImageView alloc] initWithImage:[UIImage imageNamed:@"listing.PNG"]]];
customButtonItem.style = UIBarButtonItemStyleBordered;

并将 willHideViewController 更新为：

-(void)splitViewController:(UISplitViewController *)svc 
    willHideViewController:(UIViewController *)aViewController 
         withBarButtonItem:(UIBarButtonItem *)barButtonItem 
      forPopoverController:(UIPopoverController *)pc
{
    //If this bar button item doesn't have a title, it won't appear at all
    customButtonItem.target = barButtonItem.target;
    customButtonItem.action = barButtonItem.action;
    barButtonItem = customButtonItem;
    [barButtonItem setTitle:@""];

    //barButtonItem = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemOrganize target:[barButtonItem target] action:[barButtonItem action]];
    //[barButtonItem setImage:[UIImage imageNamed:@"listing.png"]];

    //Take this bar button item and put it on the left side of our nav item
    [[self navigationItem] setLeftBarButtonItem:barButtonItem];
    self.popoverController = pc;
}

这导致图像在我想要的时间/位置显示，但按钮没有边框（尽管我将其设置为）并且不显示弹出框。

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1 回答 1

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编辑：我错过了这是 splitView 委托，而您正在从 iOS 接收 UIBarButtonItem。所以我建议你做的是尝试以下。

创建自己的 buttonItem，并从系统提供的目标和选择器中复制目标和选择器。像这样创建新的按钮项：

UIBarButtonItem *newBut = [[UIBarButtonItem alloc] initWithImage:image style:UIBarButtonItemStyleBordered target: barButtonItem.target action: barButtonItem.action];
[[self navigationItem] setLeftBarButtonItem:newBut];
于 2012-08-03T23:33:43.900 回答