如何在ios的其他功能中获取集合单元格？

Posted 2023-03-16

【中文标题】如何在ios的其他功能中获取集合单元格？

【英文标题】：How to get the collection cell in other function in ios?

【发布时间】：2015-11-14 07:58:55

【问题描述】：

我有 UICollectionView，其中包含这么多自定义单元格。当用户长按然后单元格开始晃动并在其上添加删除按钮时，我有一个长按手势。当我按下删除按钮时，单元格将从集合中删除查看。

长按代码。

-(void)handleLongPress:(UILongPressGestureRecognizer *)gestureRecognizer

    p = [gestureRecognizer locationInView:self.collection_view];
    NSIndexPath *indexPath = [self.collection_view indexPathForItemAtPoint:p];
    if (gestureRecognizer.state != UIGestureRecognizerStateEnded)
    
        return;
    

    if (indexPath == nil)
    
        NSLog(@"couldn't find index path");
    
    else
    
        [[NSUserDefaults standardUserDefaults]setValue:@"yes" forKey:@"longPressed"];
        [self.collection_view reloadData];
    
    if (gestureRecognizer.state == UIGestureRecognizerStateEnded) 
        NSLog(@"UIGestureRecognizerStateEnded");
        //Do Whatever You want on End of Gesture
    
    else if (gestureRecognizer.state == UIGestureRecognizerStateBegan)
        NSLog(@"UIGestureRecognizerStateBegan.");
        //Do Whatever You want on Began of Gesture
    

    pgr
    = [[UIPanGestureRecognizer alloc]
       initWithTarget:self action:@selector(handePanPress:)];
    // To detect after how many seconds you want shake the cells
    pgr.delegate = self;
    [self.collection_view addGestureRecognizer:pgr];

    //show the done button here
    navButtonDone = [[UIBarButtonItem alloc] initWithTitle:@"Done" style:UIBarButtonItemStylePlain target:self action:@selector(navBtnDone:)];
    self.navigationItem.rightBarButtonItem = navButtonDone;

当长手势开始时，我还会在按下导航栏按钮时在导航栏上添加右键，我会停止动画并删除删除按钮。我可以删除 iPhone 5s 中的删除按钮，但不能在 iPhone 6 中删除。

下面是代码

- (IBAction)navBtnDone:(id)sender

        if([[[NSUserDefaults standardUserDefaults]valueForKey:@"longPressed"] isEqualToString:@"yes"])
        
            [[NSUserDefaults standardUserDefaults]setValue:@"no" forKey:@"longPressed"];
            [_deleteButton removeFromSuperview];
            [self.collection_view reloadData];
            [self.collection_view removeGestureRecognizer:pgr];
            self.navigationItem.rightBarButtonItem=nil;
        

这里我刚刚添加了[_deleteButton removeFromSuperview]; 如何在每个函数中获取单元格并删除删除按钮。

【参考方案1】：

要根据索引路径检索单元格，您可以调用

UICollectionViewCell *someCell = [myCollectionView cellForItemAtIndexPath:indexPath];

然后删除删除按钮

if (someCell) 
    // Remove the delete button on the cell.
    [someCell.deleteButton removeFromSuperView];

【参考方案2】：

有两种方法。

将 IndexPath 存储在全局变量中。

在您的 .h 中

 NSIndexPath *globalIndexPath

在您的手势识别器中

-(void)handleLongPress:(UILongPressGestureRecognizer *)gestureRecognizer

   p = [gestureRecognizer locationInView:self.collection_view];
   globalIndexPath = [self.collection_view indexPathForItemAtPoint:p];
   //Other Stuff

在您的删除按钮操作中

- (IBAction)navBtnDone:(id)sender

   //Other Stuff
   UICollectionViewCell *cell = [myCollectionView cellForItemAtIndexPath: globalIndexPath];
   if (cell) 
     [cell.deleteButton removeFromSuperView];
   

将 Indexpath.row 值设置为 Barbutton 的标记值

-(void)handleLongPress:(UILongPressGestureRecognizer *)gestureRecognizer
 
   p = [gestureRecognizer locationInView:self.collection_view];
   NSIndexPath *indexPath = [self.collection_view indexPathForItemAtPoint:p];
   //Other Stuff
   //show the done button here
   navButtonDone = [[UIBarButtonItem alloc] initWithTitle:@"Done" style:UIBarButtonItemStylePlain target:self action:@selector(navBtnDone:)];
   navButton.tag = indexPath.row //IMPORTANT
   self.navigationItem.rightBarButtonItem = navButtonDone;

在您的按钮操作中

- (IBAction)navBtnDone:(id)sender

   UIBarButtonItem *btn = (UIBarButtonItem *)sender;
   UItableViewCell *cell = [myCollectionView cellForItemAtIndexPath: [NSIndexPath indexPathWithRow: btn.tag inSection:0]];
   [cell.deleteButton removeFromSuperView];