ios - UICollectionView allowsMultipleSelections 不工作

Question

我正在尝试使用 CollectionView 制作一些 photoPicker。

有

allowsMultipleSelection = YES

使用以下方法

- (void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath {

    selectedPictures = [NSMutableArray array];

    [selectedPictures addObject:[imagesArray objectAtIndex:indexPath.item]];

    NSLog(@"Selected list:\n %@", selectedPictures);

    NSLog(@"Objects in Array %i", selectedPictures.count);

}

当我选择单元格时，它总是根据它的 indexPath 只向 MutableArray 添加一个对象。可能是什么问题？

Answer 1

为什么不将selectedPictures 保留为成员变量

在你的代码中

- (void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath {

selectedPictures = [NSMutableArray array]; //keep on creation the new array on each selection

[selectedPictures addObject:[imagesArray objectAtIndex:indexPath.item]]; //adding the selected images means single image 

NSLog(@"Selected list:\n %@", selectedPictures);

NSLog(@"Objects in Array %i", selectedPictures.count);

}

试试这个

把他放在viewDidLoad

- (void)viewDidLoad
  {
    selectedPictures =  [[NSMutableArray alloc]init]; //initilise hear
  }



 - (void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath {

   //  selectedPictures = [NSMutableArray array]; //keep on creation the new array on each selection

[selectedPictures addObject:[imagesArray objectAtIndex:indexPath.item]]; //adding the   selected images means single image to already initialised array 

 NSLog(@"Selected list:\n %@", selectedPictures);

 NSLog(@"Objects in Array %i", selectedPictures.count);

}

希望这对你有帮助.. :)