objective-c - UIBarButtonItem with UIButton as CustomView - 从 UIButton，如何访问它的 UIBarButtonItem？

Question

我有一个 UIBarButtonItem 和 UIButton 作为自定义 View 。

UIButton 上有一个 addTarget:action:。在 Action 中，我展示了一个弹出窗口。我目前正在从 sender.frame(UIButton 的框架)进行展示，我想从 UIBarButtonItem 进行展示。

如何从 UIButton 访问 UIBarButtonItem？

Answer 1

如果您已将 UIButton 设置为 UIBarButtonItem 的 customView 或自定义 View 的 subview ，那么您可以向上走从按钮开始的 View 层次结构，直到找到包含该按钮的 UIToolbar 或 UINavigationBar，然后在栏的项目中搜索其自定义 View 是按钮(或祖先 View )的项目按钮)。

这是我完全未经测试的代码。您可以调用 [[self class] barButtonItemForView:myButton] 来获取包含您的按钮的项目。

+ (BOOL)ifBarButtonItem:(UIBarButtonItem *)item containsView:(UIView *)view storeItem:(UIBarButtonItem **)outItem {
    UIView *customView = item.customView;
    if (customView && [view isDescendantOfView:customView]) {
        *outItem = item;
        return YES;
    } else {
        return NO;
    }
}

+ (BOOL)searchBarButtonItems:(NSArray *)items forView:(UIView *)view storeItem:(UIBarButtonItem **)outItem {
    for (UIBarButtonItem *item in items) {
        if ([self ifBarButtonItem:item containsView:view storeItem:outItem])
            return YES;
    }
    return NO;
}

+ (UIBarButtonItem *)barButtonItemForView:(UIView *)view {
    id bar = view;
    while (bar && !([bar isKindOfClass:[UIToolbar class]] || [bar isKindOfClass:[UINavigationBar class]])) {
        bar = [bar superview];
    }
    if (!bar)
        return nil;

    UIBarButtonItem *item = nil;

    if ([bar isKindOfClass:[UIToolbar class]]) {
        [self searchBarButtonItems:[bar items] forView:view storeItem:&item];
    }

    else {
        UINavigationItem *navItem = [bar topItem];
        if (!navItem)
            return nil;
        [self ifBarButtonItem:navItem.backBarButtonItem containsView:view storeItem:&item]
        || [self ifBarButtonItem:navItem.leftBarButtonItem containsView:view storeItem:&item]
        || [self ifBarButtonItem:navItem.rightBarButtonItem containsView:view storeItem:&item]
        || ([navItem respondsToSelector:@selector(leftBarButtonItems)]
            && [self searchBarButtonItems:[(id)navItem leftBarButtonItems] forView:view storeItem:&item])
        || ([navItem respondsToSelector:@selector(rightBarButtonItems)]
            && [self searchBarButtonItems:[(id)navItem rightBarButtonItems] forView:view storeItem:&item]);
    }

    return item;
}