我有一个问题，我有2 leftBarButtonItems。在Mac Catalyst上，firstButton指向一个不支持的操作:用AVFoundation录制视频。Mac Catalyst上只有第二个按钮有效:使用UIImagePickerController。

所以在Mac Catalyst上，我必须将第一个UIBarButtonItem指向secondButton，并始终隐藏第二个UIBarButtonItem。在iOS上，两个按钮都应该显示出来。这就是我的解决方案:

#if TARGET_OS_MACCATALYST
        self.navigationItem.leftBarButtonItem = self.secondButton;
        NSUInteger count = [self.navigationItem.leftBarButtonItems count];
        for (NSUInteger i = 0; i < count; i++) {
            UIBarButtonItem *thisButton = [self.navigationItem.leftBarButtonItems objectAtIndex:i];
            if (i == 1) {
                thisButton.enabled = NO;
                thisButton.tintColor = [UIColor clearColor];
            }
        }
#else
        self.navigationItem.leftBarButtonItem = self.firstButton;
#endif

我希望它能帮助到有类似问题的人。

将你的按钮保存在一个强outlet中(让我们称之为myButton)，然后添加/删除它:

// Get the reference to the current toolbar buttons
NSMutableArray *toolbarButtons = [self.toolbarItems mutableCopy];

// This is how you remove the button from the toolbar and animate it
[toolbarButtons removeObject:self.myButton];
[self setToolbarItems:toolbarButtons animated:YES];

// This is how you add the button to the toolbar and animate it
if (![toolbarButtons containsObject:self.myButton]) {
    // The following line adds the object to the end of the array.  
    // If you want to add the button somewhere else, use the `insertObject:atIndex:` 
    // method instead of the `addObject` method.
    [toolbarButtons addObject:self.myButton];
    [self setToolbarItems:toolbarButtons animated:YES];
}

因为它存储在输出中，所以即使它不在工具栏上，您也将保留对它的引用。

自定义

最后，在iOS 16+中，UIBarButtonItem有isHidden属性。

所以，扩展现有的答案，比如

extension UIBarButtonItem {
    func show() {
        if #available(iOS 16.0, *) {
            isHidden = false
        } else {
            isEnabled = true
            tintColor = .white
        }
    }
    
    func hide() {
        if #available(iOS 16.0, *) {
            isHidden = true
        } else {
            isEnabled = false
            tintColor = .clear
        }
    }
}

只需设置barButton。customView = UIView()，看看窍门

来自@lnafziger的回答

将你的Barbuttons保存在一个强大的outlet中，并这样隐藏/显示它:

-(void) hideBarButtonItem :(UIBarButtonItem *)myButton {
    // Get the reference to the current toolbar buttons
    NSMutableArray *navBarBtns = [self.navigationItem.rightBarButtonItems mutableCopy];

    // This is how you remove the button from the toolbar and animate it
    [navBarBtns removeObject:myButton];
    [self.navigationItem setRightBarButtonItems:navBarBtns animated:YES];
}


-(void) showBarButtonItem :(UIBarButtonItem *)myButton {
    // Get the reference to the current toolbar buttons
    NSMutableArray *navBarBtns = [self.navigationItem.rightBarButtonItems mutableCopy];

    // This is how you add the button to the toolbar and animate it
    if (![navBarBtns containsObject:myButton]) {
        [navBarBtns addObject:myButton];
        [self.navigationItem setRightBarButtonItems:navBarBtns animated:YES];
    }
}

当需要使用以下功能..

[self showBarButtonItem:self.rightBarBtn1];
[self hideBarButtonItem:self.rightBarBtn1];