UIMenuController在Cell内部无法显示的解决办法（iOS9.2）

@implementation CollectionViewCell //继承自UICollectionViewCell

 

 UILongPressGestureRecognizer *longPress = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(longPress:)];
 longPress.minimumPressDuration = 1;
 [self addGestureRecognizer:longPress];//添加长按手势
//实现长按方法
- (void)longPress:(UILongPressGestureRecognizer *)gesture
{
 switch (gesture.state) {
 case UIGestureRecognizerStateBegan:
 {

  [self becomeFirstResponder];<span style="color: rgb(255, 0, 0);">//必须有！</span>
  UIMenuController *menu = [UIMenuController sharedMenuController];
  UIMenuItem *item1 = [[UIMenuItem alloc] initWithTitle:@"保存" action:@selector(savePic)];
  menu.menuItems = [NSArray arrayWithObject:item1];
  [menu setTargetRect:self.scView.frame inView:self.scView.superview];
  [menu setMenuVisible:YES animated:YES];
 }

  break;
 default:
  break;
 }

}


<span style="color: rgb(0, 128, 0);">//必须实现。注意不是- (BOOL)becomeFirstResponder方法</span>
- (BOOL)canBecomeFirstResponder
{
 return YES;
}