ios - 将 UIBarButtonItem 与图像或系统预设一起用于 SplitView/Popover 控件

Question

我目前正在优化 iPad 的应用程序，并希望使用带有图像的 UIBarButtonItem 来呈现弹出窗口。如果我使用的是带标题的按钮，那么我目前使用的代码效果很好，但我更愿意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，它就不会显示。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，因为我正在为横向使用 Split View)。

使用 setImage、setTitle 的任意组合或将按钮初始化为系统预设均无效。当检测到横向旋转但它仍然在屏幕上时，我还尝试将带有系统预设的按钮设置为零。我不确定如何从这里开始，但我真的很想避免为此按钮使用字符串，而且我非常想知道为什么会这样。

代码如下:

#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:

我将其添加到我的 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/地点显示，但按钮没有边框(尽管我将其设置为)并且不显示弹出窗口。

Answer 1

编辑:我没有注意到这是 splitView 委托(delegate)，而您正在从 iOS 接收 UIBarButtonItem。所以我建议您尝试以下操作。

创建您自己的按钮项，并从系统提供的目标和选择器中复制。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];