iOS7中的UIMenuController

Question

我实际上对iOS7中用于在UITableView上显示自定义上下文菜单的更改感到困惑.

我的代码如下:

- (void)viewDidLoad {
   UIMenuItem *deleteAction = [[UIMenuItem alloc]initWithTitle:NSLocalizedString(@"Delete", nil) action:@selector(delete:)];
   UIMenuItem *renameAction = [[UIMenuItem alloc]initWithTitle:NSLocalizedString(@"Rename", nil) action:@selector(rename:)];
   UIMenuController* mc = [UIMenuController sharedMenuController];
   mc.menuItems = [NSArray arrayWithObjects: renameAction, deleteAction, nil];
   [mc setTargetRect:CGRectMake(50.0, 50.0, 0, 0) inView:self.view];
   [mc setMenuVisible:YES animated:YES];
   [mc setMenuItems:@[deleteAction, renameAction]];
   [self becomeFirstResponder];

-(void)tableView:(UITableView*)tableView performAction:(SEL)action forRowAtIndexPath:(NSIndexPath*)indexPath withSender:(id)sender{
}

-(BOOL)tableView:(UITableView*)tableView canPerformAction:(SEL)action forRowAtIndexPath:(NSIndexPath*)indexPath withSender:(id)sender {
if (tableView != nil && indexPath != nil)
{
    if (action == @selector(delete:)) {
            return YES;
        }
        if (action == @selector(rename:)) {
            return YES;
        }
    }
    return NO;
}

-(BOOL)tableView:(UITableView*)tableView shouldShowMenuForRowAtIndexPath:(NSIndexPath*)indexPath {
    return YES;
}

我的问题是,在iOS的预览版本中一切正常.如果用户长按了tableview的单元格,则会出现自定义上下文菜单,但在iOS7中没有任何操作.方法被调用但没有显示.

Answer 1

UIMenuController有一个小问题让人们总是想念.

要显示菜单,目标视图必须位于响应程序链中.默认情况下,许多UIKit视图不能成为响应者,因此您需要将它们子类化为canBecomeFirstResponder返回YES.

-(BOOL)canBecomeFirstResponder {
    return YES;
}

- (void)menuDelete:(id)sender {
    NSLog(@"delete");
}

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {

    NSLog(@"touchesBegan");

    [self becomeFirstResponder];
    UIMenuItem *menuItem = [[UIMenuItem alloc] initWithTitle:@"Delete" action:@selector(menuDelete:)];
    UIMenuController *menuCont = [UIMenuController sharedMenuController];
    [menuCont setTargetRect:self.frame inView:self.superview];
    menuCont.menuItems = [NSArray arrayWithObject:menuItem];
    [menuCont setMenuVisible:YES animated:YES];
}

我希望这有帮助.我很乐意帮助解决更多问题,所以如果我的建议仍然无法解决问题,请随时提供更新.