Question

在我覆盖UICollectionViewFlowLayout后，它会显示3个警告，如下所示

仅针对UICollectionViewFlowLayout缓存不匹配的框架记录一次
UICollectionViewFlowLayout缓存了索引路径{length = 2，path = 0 - 1}的帧不匹配 - 缓存值：{{145,0}，{130,130}};预期价值：{{5,141}，{130,130}}
这可能是因为流布局子类FullyHorizontalFlowLayout正在修改UICollectionViewFlowLayout返回的属性而不复制它们

我使用＆＃39; FullyHorizontalFlowLayout＆＃39;使i单元格从左到右排列（原始是从上到下）。以下是我的layoutAttributesForElementsInRect＆＃39;代码

-(NSArray*)layoutAttributesForElementsInRect:(CGRect)rect
{
CGFloat newX = MIN(0, rect.origin.x - rect.size.width/2);
CGFloat newWidth = rect.size.width*2 + (rect.origin.x - newX);

CGRect newRect = CGRectMake(newX, rect.origin.y, newWidth, rect.size.height);

// Get all the attributes for the elements in the specified frame
NSArray *allAttributesInRect = [super layoutAttributesForElementsInRect:newRect];

for (UICollectionViewLayoutAttributes *attr in allAttributesInRect) {
    UICollectionViewLayoutAttributes *newAttr = [self layoutAttributesForItemAtIndexPath:attr.indexPath];

    attr.frame = newAttr.frame;

    attr.center = newAttr.center;
    attr.bounds = newAttr.bounds;
    attr.hidden = newAttr.hidden;
    attr.size = newAttr.size;

}
return allAttributesInRect;
}

Answer 1

您应该使用以下片段深度复制支持属性数组：

Apple

覆盖UICollectionViewFlowLayout后，它只显示一次缓存不匹配帧的日志记录

1 个答案: