ios - 当我调用 CollectionView :didSelectItemAtIndexPath 时没有任何反应

Question

我正在尝试调用突出显示我拥有的 UICollectionViewCells 的方法。一切正常，但是当 UIView 首次加载时，我正尝试像这样选择 Collection View 中的第一项

[photoCollectionView selectItemAtIndexPath:[NSIndexPath indexPathForRow:0 inSection:0] animated:YES scrollPosition:UICollectionViewScrollPositionNone];

这就是我的选择方法，在选择照片时效果很好。

#pragma mark -- UICollectionView Delegate
- (void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath
{
    oldCell = currentCell;
    currentCell = indexPath;

    // animate the cell user tapped on
    UICollectionViewCell  *cell = [collectionView cellForItemAtIndexPath:indexPath];
    UICollectionViewCell *oCell = [collectionView cellForItemAtIndexPath:oldCell];

    NSDictionary *currentSelectedDict = [imageArray objectAtIndex:indexPath.row];
    UIImage *updatePreviewImage = [UIImage imageWithData:[currentSelectedDict objectForKey:@"DImage"]];
    [previewImageView setImage:updatePreviewImage];
    previewImageView.userInteractionEnabled = YES;

    typeTextF.text = [currentSelectedDict objectForKey:@"DocumentType"];
    descriptionText.text = [currentSelectedDict objectForKey:@"DocumentDescription"];
    dateLabel.text = [NSString stringWithFormat:@"%@", [currentSelectedDict objectForKey:@"DateString"]];


    [UIView animateWithDuration:0.2
                          delay:0
                        options:(UIViewAnimationOptionAllowUserInteraction)
                     animations:^{
                         NSLog(@"animation start");
                         [cell setBackgroundColor:[UIColor whiteColor]];
                         [oCell setBackgroundColor:[UIColor clearColor]];
                     }
                     completion:^(BOOL finished){
                         NSLog(@"animation end");
                         [cell setBackgroundColor:[UIColor whiteColor]];
                         [oCell setBackgroundColor:[UIColor clearColor]];
                     }
     ];


}

我读到也许您可以过早调用此方法？我不确定情况是否如此，但我不知道如何测试它，或者我使用的代码是否正确。

Answer 1

试试这个。覆盖 UICollectionViewCell 类并添加此方法

- (void)setSelected:(BOOL)selected
{
    [super setSelected:selected];

        [UIView animateWithDuration:1.0 delay:0 options:UIViewAnimationOptionAllowUserInteraction animations:^{

            self.contentView.backgroundColor = [UIColor redColor];
        } completion:^(BOOL finished) {
            self.contentView.backgroundColor = [UIColor greenColor];
        }];     
}