ios - "no UICollectionViewLayoutAttributes instance"是什么意思？

Question

我的 ios 应用程序崩溃，但出现以下异常:

void HandleExceptions(NSException *__strong):875 ERROR: uncaught exception: no UICollectionViewLayoutAttributes instance for -layoutAttributesForDecorationViewOfKindOfKind: ColorDecoratorView at path <NSIndexPath: 0x7d843ec0> {length = 3, path = 3 - 0}

你能告诉我“-layoutAttributesForDecorationViewOfKindOfKind 没有 UICollectionViewLayoutAttributes 实例”是什么意思吗？我应该去哪里解决问题？

我已经实现了这种方法:

   - (UICollectionViewLayoutAttributes *)layoutAttributesForDecorationViewOfKind:(NSString *)decorationViewKind atIndexPath:(NSIndexPath *)indexPath

但是当我旋转屏幕时出现以下异常:

uncaught exception: layout attributes for supplementary item at index path (<NSIndexPath: 0x79ef2c80> {length = 2, path = 1 - 0}) changed from <UICollectionViewLayoutAttributes: 0x82e76830> index path: (<NSIndexPath: 0x79ebf750> {length = 2, path = 1 - 0}); element kind: (ColorDecoratorView); frame = (72 2513; 293.333 252);  to <UICollectionViewLayoutAttributes: 0x79ef9380> index path: (<NSIndexPath: 0x79ef2c80> {length = 2, path = 1 - 0}); element kind: (ColorDecoratorView); frame = (0 825; 1024 -327);  without invalidating the layout

谢谢你。

Answer 1

你在实现这个方法吗？
- (UICollectionViewLayoutAttributes *)layoutAttributesForDecorationViewOfKind:(NSString *)decorationViewKind atIndexPath:(NSIndexPath *)indexPath
返回值为
A layout attributes object containing the information to apply to the decoration view.
我会说实现这个方法。像这样的东西
UICollectionViewLayoutAttributes *attrs = [UICollectionViewLayoutAttributes layoutAttributesForDecorationViewOfKind:decorationViewKind withIndexPath:indexPath];
attrs.frame = cgrectmake (x,x,x,x);
return attrs;
看起来您的单元格正在从 Collection View 中请求一些 layoutAttributes。
NSIndexPath 似乎是 [L=3, path = 3];

获取 indexPath.row 并在 cellForRowAtIndexPath 中进一步调查。