iphone - 如何显示 UIMenuController 到 UIBarButtonItem

Question

如何在 UIBarButtonItem 下显示 UIMenuController 点击它？

Answer 1

假设您的 UIBarButtonItem 已连接到:

-(void)buttonClicked:(UIBarButtonItem*)sender event:(UIEvent*)event;

然后将这些代码粘贴到您的 View Controller 中:

-(void)buttonClicked:(UIBarButtonItem*)sender event:(UIEvent*)event{
    [self becomeFirstResponder];

    /*get the view from the UIBarButtonItem*/
    UIView *buttonView=[[event.allTouches anyObject] view];
    CGRect buttonFrame=[buttonView convertRect:buttonView.frame toView:self.view];

    UIMenuController *menuController = [UIMenuController sharedMenuController];
    UIMenuItem *resetMenuItem = [[UIMenuItem alloc] initWithTitle:@"Menu Item" action:@selector(menuItemClicked:)];

    NSAssert([self becomeFirstResponder], @"Sorry, UIMenuController will not work with %@ since it cannot become first responder", self);
    [menuController setMenuItems:[NSArray arrayWithObject:resetMenuItem]];
    [menuController setTargetRect:buttonFrame inView:self.view];
    [menuController setMenuVisible:YES animated:YES];

    [resetMenuItem release];
}
- (void) copy:(id) sender {
    // called when copy clicked in menu
}
- (void) menuItemClicked:(id) sender {
    // called when Item clicked in menu
}
- (BOOL) canPerformAction:(SEL)selector withSender:(id) sender {
    if (selector == @selector(menuItemClicked:) /*|| selector == @selector(copy:)*/ /*<--enable that if you want the copy item */) {
        return YES;
    }
    return NO;
}
- (BOOL) canBecomeFirstResponder {
    return YES;
}

关键是对 canBecomeFirstResponder 和 canPerformAction 返回 YES。

Here是示例项目，如果您需要的话。

这些代码实际上来自stackoverflow的其他帖子，我只是将它们组合在一起。

Figure out UIBarButtonItem frame in window?

How to get UIMenuController work for a custom view?