UICollectionView的单元格消失了 [英] UICollectionView's cell disappearing
问题描述
发生了什么
目前我的应用程序内部使用了两个 UICollectionViews a UITableView 。这样我创建了一个类似应用程序的Pulse News。我的问题是，有时第6行和第11行完全消失，留下一个空白区域应该是单元格。我真的不介意，如果所有细胞都是这样的（这种方式我可以假设我没有做正确的事情），但问题是，正好发生在那些特定的细胞上。
Currently I have an application that uses two UICollectionViews inside a UITableView. This way I create a Pulse News look like application. My problem with this is that sometimes the 6th and 11th row disappears completely, leaving a blank space where it should be the cell. I wouldn't actually mind, if all the cells were like this (and this way I could assume that I wasn't doing things correctly), but the thing is, is just happening with those specific ones.
我的理论
第6行和第11行是我开始滚动时出现的行，所以默认我能看到5个单元格，当我第一次水平滚动时，第6个出现（有时是空白）。
The 6th and 11th rows are the ones that appears when I start scrolling, so by default I am able to see 5 cells, and when I do the first horizontal scrolling the 6th comes up (blank space sometimes).
我拥有什么
我目前唯一做的事情是这个：
The only thing I am doing at the moment is this:
[self.collectionView registerNib:[UINib nibWithNibName:CELL_NIB_NAME bundle:nil] forCellWithReuseIdentifier:CELL_IDENTIFIER];
在 viewDidLoad 上。在创建单元格时：
On the viewDidLoad. And on the creation of the cell:
- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath
{
MyCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:CELL_IDENTIFIER forIndexPath:indexPath];
NSMutableDictionary *dictionary = [self.DataSource objectAtIndex:[indexPath row]];
[cell buildViewWithDictionary:dictionary withReferenceParent:self.referenceViewController];
return cell;
}
所以在我的提示中没有任何花哨的事情发生在这里。我虽然在数据源（虚拟JSON文件）上有问题，但有时它工作正常并且单元格显示，所以我想从那部分是可以的。
So on my understating nothing fancy going on here. I though there was something wrong on the data source (a dummy JSON file), but sometimes it works ok and the cell shows, so I guess from that part is ok.
所以我的问题：有谁知道发生了什么？我真的不想说这是来自iOS的错误，但我想不出别的。
So my "question": Does anyone knows what's going on? I don't really like to say that it's a bug from iOS, but I can't think of anything else.
编辑1.0
令人惊讶的是这个方法
-(UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath;
来自 indexPath [0,4 ]到[0,6]而不计算[0,5]。我第一次在iOS中看到这种情况。
Is going from indexPath [0,4] to [0,6] without calculating the [0,5]. First time I actually see this happening in iOS.
编辑2.0
我已经改变了创建单元格的方式，而不是出列我使用旧方式：
I have switched the way I am creating the cells, and instead of dequeuing I am using the old way:
NSArray *nib = [[NSBundle mainBundle] loadNibNamed:CELL_NIB_NAME owner:self options:nil];
MyCell *cell = (MyCell *)[nib objectAtIndex:0];
仍然是同样悲伤的结果。
Still the same sad result.
推荐答案
那么，有什么用呢？
1）子类 UICollectionViewFlowLayout 。
2）将我的 UICollectionView 的flowLayout设置为我的新子类。
2) Set the flowLayout of my UICollectionView to my new subclass.
3）在<$ c的init方法上$ c> UICollectionViewFlowLayout 子类，设置你想要的方向：
3) On the init method of the UICollectionViewFlowLayout subclass, set the orientation you want:
self.scrollDirection = UICollectionViewScrollDirectionHorizontal;
在我的情况下，它是水平的。
In my case it is Horizontal.
4）重要部分：
-(BOOL)shouldInvalidateLayoutForBoundsChange:(CGRect)newBounds
{
return YES;
}
此刻，我应该提出一点理论，但说实话，我不这样做有线索。
At this moment, I should theorise a bit, but honestly I don't have a clue.
这篇关于UICollectionView的单元格消失了的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
