Question

我正在尝试在阅读apple文档后使用以下函数删除collectionView的全部内容。

https://developer.apple.com/library/ios/documentation/WindowsViews/Conceptual/CollectionViewPGforIOS/CreatingCellsandViews/CreatingCellsandViews.html#//apple_ref/doc/uid/TP40012334-CH7-SW7

最终会出现以下错误。

由于未捕获的异常'NSInternalInconsistencyException'而终止应用，原因：'无效更新：无效的节数。更新（0）后集合视图中包含的节数必须等于更新前的集合视图中包含的节数（5），加上或减去插入或删除的节数（插入0，0删除）。“

这是什么意思？或者任何人都可以向我展示一个参考链接，其中包含如何使用一组新数据刷新collectionView内容的示例。

-(void) clearCollectionViewAndDataArray
{

[self.galleryCollectionView performBatchUpdates:^{
    [displayDataArray removeAllObjects];
    NSLog(@"Is it empty---?%@",displayDataArray);
  [self.galleryCollectionView deleteItemsAtIndexPaths:[self createIndexPathArrayEntireCollectionView]];
}
completion:nil ];
}




-(NSMutableArray*) createIndexPathArrayEntireCollectionView
{

NSMutableArray* indexPathArray = [[NSMutableArray alloc] init];

for(int i=0; i < [displayDataArray count]; i++)
{

    NSMutableArray* sectionArray=[[NSMutableArray alloc] init];
    sectionArray=[displayDataArray objectAtIndex:i];
    for(int j=0; j < [sectionArray count]; j++)
    {
        NSIndexPath* newPath = [NSIndexPath indexPathForRow:j inSection:i];
        [indexPathArray addObject: newPath];
    }

}

return indexPathArray;

}

使用的NSMutableArray数据是：

(
(
"<SACatalogs: 0x9554750>",
    "<SACatalogs: 0x953d9c0>",
    "<SACatalogs: 0x953e050>"
),
    (
    "<SACatalogs: 0x953e6e0>",
    "<SACatalogs: 0x953ed70>",
    "<SACatalogs: 0x953f420>"
),
    (
    "<SACatalogs: 0x953fab0>",
    "<SACatalogs: 0x9540160>",
    "<SACatalogs: 0x95407f0>"
),
    (
    "<SACatalogs: 0x9540ec0>",
    "<SACatalogs: 0x9541530>",
    "<SACatalogs: 0x9541be0>"
),
    (
    "<SACatalogs: 0x9542290>",
    "<SACatalogs: 0x9542940>",
    "<SACatalogs: 0x9542ff0>"
)
)

使用的索引路径是

"<NSIndexPath 0xa6bb9a0> 2 indexes [0, 0]",
"<NSIndexPath 0xa648bc0> 2 indexes [0, 1]",
"<NSIndexPath 0xa6dcdc0> 2 indexes [0, 2]",
"<NSIndexPath 0xa6c7d00> 2 indexes [1, 0]",
"<NSIndexPath 0xa6c91c0> 2 indexes [1, 1]",
"<NSIndexPath 0xa6f6100> 2 indexes [1, 2]",
"<NSIndexPath 0xa6490d0> 2 indexes [2, 0]",
"<NSIndexPath 0xa6a93b0> 2 indexes [2, 1]",
"<NSIndexPath 0xa6d08b0> 2 indexes [2, 2]",
"<NSIndexPath 0xa64ddb0> 2 indexes [3, 0]",
"<NSIndexPath 0xa6f7380> 2 indexes [3, 1]",
"<NSIndexPath 0xa6c1c90> 2 indexes [3, 2]",
"<NSIndexPath 0xa6e45f0> 2 indexes [4, 0]",
"<NSIndexPath 0xa6bf840> 2 indexes [4, 1]",
"<NSIndexPath 0xa6a03f0> 2 indexes [4, 2]"

}

先谢谢

Answer 1

似乎首先从displayDataArray删除所有对象，然后计算来自indexPathArray的{{1}}。因此displayDataArray将为空和

indexPathArray

没有。将订单更改为

[self.galleryCollectionView deleteItemsAtIndexPaths:[self createIndexPathArrayEntireCollectionView]];

可以解决问题。但正如评论中所提到的，你可以打电话如果所有集合视图项已被删除，则[self.galleryCollectionView deleteItemsAtIndexPaths:[self createIndexPathArrayEntireCollectionView]]; [displayDataArray removeAllObjects];。

使用一组新数据刷新UICollectionView

1 个答案: