Question

如何在长按手势后更改单元格imageview？

当我点击一个单元格（longpress）时会显示4个自定义项目，但当我选择其中一个时，应用程序崩溃。（如果删除：（Cell *）单元格和cell.imageView.image = [UIImage imageNamed：[NSString stringWithFormat：@“ICUbedRED.png”]];它有效...我的意思是alertView出现但当然图像没有不要改变。

 - (void)longPress:(UILongPressGestureRecognizer *)recognizer {
    if (recognizer.state == UIGestureRecognizerStateBegan) {
        Cell *cell = (Cell *)recognizer.view;
        [cell becomeFirstResponder];

        UIMenuItem *highDep = [[UIMenuItem alloc] initWithTitle:@"High Dependency" action:@selector(hiDep:)];
        UIMenuItem *lowDep = [[UIMenuItem alloc] initWithTitle:@"Low Dependency" action:@selector(lowDep:)];
        UIMenuItem *booked = [[UIMenuItem alloc] initWithTitle:@"Booked"     action:@selector(booked:)];
        UIMenuItem *free = [[UIMenuItem alloc] initWithTitle:@"Free" action:@selector(free:)];

            UIMenuController *menu = [UIMenuController sharedMenuController];
    [menu setMenuItems:[NSArray arrayWithObjects:booked, highDep, lowDep, free, nil]];
        [menu setTargetRect:cell.frame inView:cell.superview];
        [menu setMenuVisible:YES animated:YES];



   }
}

空洞是：

 - (void)hiDep:(Cell*)cell
 {
    NSLog(@"Bed is HiDep");

    cell.imageView.image = [UIImage imageNamed:[NSString stringWithFormat:@"ICUbedRED.png"]];




     UIAlertView *testAlert = [[UIAlertView alloc] initWithTitle:@"This Bed is High     Dependency"
                                                message:@""
                                               delegate:self cancelButtonTitle:@"OK"       otherButtonTitles:nil, nil];



    [testAlert show];
    [testAlert release];


  }

- (void)lowDep:(Cell*)cell
 {.
    cell.imageView.image = [UIImage imageNamed:[NSString     stringWithFormat:@"ICUbedYELLOW.png"]];
..}

 - (void)free:(Cell*)cell
 {..
    cell.imageView.image = [UIImage imageNamed:[NSString stringWithFormat:@"ICUbedGREEN.png"]];
.}

 - (void)booked:(Cell*)cell
 {..
    cell.imageView.image = [UIImage imageNamed:[NSString stringWithFormat:@"ICUbedBLUE.png"]];
.}

，细胞构建方法是：

- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView     cellForItemAtIndexPath:(NSIndexPath *)indexPath{

     static NSString *identifier = @"Cell";
    Cell *cvc = (Cell *)[collectionView dequeueReusableCellWithReuseIdentifier:identifier forIndexPath:indexPath];

    int i = indexPath.row%[labelArray count];
    number = i;

    UILongPressGestureRecognizer *recognizer = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(longPress:)];



    [cvc addGestureRecognizer:recognizer];


    cvc.imageView.image = [UIImage imageNamed:[NSString stringWithFormat:@"icubed.png"]];
    cvc.label.text =  [labelArray objectAtIndex:number];

       return cvc;


}

Answer 1

@dottorfeelgood

崩溃了

cell.imageView.image = [UIImage imageNamed:[NSString stringWi......

因为，该对象作为

等方法的param复活

（无效）lowDep：（小区*）细胞不属于Class Cell，被修复的param属于UIMenuItem类。因为你点击了menuItems而不是Cell。

默认情况下，您可以使用UICollectionView提供的UICollectionCell解决方案上的MenuItems和相应操作，而不是执行您现在正在执行的操作。您可以查看本教程here！

只需实现3个委托方法和

// These methods provide support for copy/paste actions on cells.
// All three should be implemented if any are.
- (BOOL)collectionView:(UICollectionView *)collectionView shouldShowMenuForItemAtIndexPath:(NSIndexPath *)indexPath;
- (BOOL)collectionView:(UICollectionView *)collectionView canPerformAction:(SEL)action forItemAtIndexPath:(NSIndexPath *)indexPath withSender:(id)sender;
- (void)collectionView:(UICollectionView *)collectionView performAction:(SEL)action forItemAtIndexPath:(NSIndexPath *)indexPath withSender:(id)sender;

并在ViewdidLoad中设置sharedMenuController所需的自定义menuItem。

希望这有帮助，请原谅我的不良判决。

longpress自定义项目UICollectionViewCell图像更改

1 个答案: