自定义UIMenuController

嗨,我想在IPhone SDK3.x中创建自定义的气泡菜单,如剪切/复制/粘贴菜单.我知道它是UIMenuController,但它只提供标准的剪切/复制/过去菜单.任何人都知道如何制作类似这样的气泡菜单.任何示例和代码供参考？

1)您需要将自定义菜单项添加到共享UIMenuController:

UIMenuItem* miCustom1 = [[[UIMenuItem alloc] initWithTitle: @"Custom 1" action:@selector( onCustom1: )] autorelease];
UIMenuItem* miCustom2 = [[[UIMenuItem alloc] initWithTitle: @"Custom 2" action:@selector( onCustom2: )] autorelease];
UIMenuController* mc = [UIMenuController sharedMenuController];
mc.menuItems = [NSArray arrayWithObjects: miCustom1, miCustom2, nil];

2)您需要在响应器链中的某处实现处理程序方法,以便在显示菜单时作为第一响应者的视图:

- (void) onCustom1: (UIMenuController*) sender
{
}

- (void) onCustom2: (UIMenuController*) sender
{
}

3)你可以选择实现canPerformAction:在响应器链中,当你显示菜单时,它将是第一响应者的视图:

- (BOOL) canPerformAction:(SEL)action withSender:(id)sender
{
    if ( action == @selector( onCustom1: ) )
    {
            return YES; // logic here for context menu show/hide
    }

    if ( action == @selector( onCustom2: ) )
    {
            return NO;  // logic here for context menu show/hide
    }

    if ( action == @selector( copy: ) )
    {
             // turn off copy: if you like:
        return NO;
    }

    return [super canPerformAction: action withSender: sender];
}

4)如果要显示菜单的视图不支持显示菜单,(例如UIWebView将在用户进行长按时显示菜单,但UILabel没有内置支持显示菜单),然后你需要自己呈现菜单.这通常通过将UILongPressGestureRecognizer附加到视图,然后在回调中显示菜单来完成:

UILongPressGestureRecognizer* gr = [[[UILongPressGestureRecognizer alloc] initWithTarget: self action: @selector( onShowMenu: ) ] autorelease];
   [_myview addGestureRecognizer: gr];



- (void) onShowMenu: (UIGestureRecognizer*) sender
{
    [sender.view becomeFirstResponder];

    UIMenuController* mc = [UIMenuController sharedMenuController];

    CGRect bounds = sender.view.bounds;

    [mc setTargetRect: sender.view.frame inView: sender.view.superview];
    [mc setMenuVisible: YES animated: YES];
}

注意,必须有一个视图声明要显示菜单的firstResponder.

5)确保您正在显示菜单的视图为canBecomeFirstResponder返回YES/TRUE.例如,如果您尝试将UILabel设为第一响应者,则它将返回NO,因此您必须将其子类化.

6)就是这样.调用操作回调时,您可能需要resignFirstResponder - 但要执行此操作,您需要实现逻辑以发现firstResponder.