滾動UICollectionView時，UICollectionView單元格在跳動

Question

大家好，我是IOS開發中的新手，我有一個UICollection，可在其中使用SDWebImageCache加載圖像。 問題是我的UICollectionview單元格在快速滾動時感覺像在抽搐或發抖。 下面我發布我的代碼以使用SDWebImageCache加載圖像

  [_homeCellImage sd_setImageWithURL:[NSURL URLWithString:[NSString stringWithFormat:@"%@%@",[dictionary objectForKey:@"user_image"],[QPCommonClass cropImageWithWidth:500 andHeight:500]]] placeholderImage:[UIImage imageNamed:@"defaultIcon"]];
    [_qpQuestionImage sd_setImageWithURL:[NSURL URLWithString:[NSString stringWithFormat:@"%@%@",[dictionary objectForKey:@"image"],[QPCommonClass cropImageWithWidth:1400 andHeight:1200]]] placeholderImage:[UIImage imageNamed:@"question"] options:0 completed:^(UIImage *image, NSError *error, SDImageCacheType cacheType, NSURL *imageURL){
        [_qpHomeActivityIndicator setHidden:YES];
        [_qpHomeActivityIndicator stopAnimating];

    }];

_homeCellImage和_qpQuestionImage是UIImageViews

Answer 1

1. 確保將圖像加載到后台線程中。
2. 加載圖像后，請確保將其緩存。

現在，當您通過cellForItem設置圖像時，可以直接從緩存中加載圖像，它應該更加平滑。

Answer 2

嘗試這樣做

[_homeCellImage setShowActivityIndicatorView:YES];

[_homeCellImage setIndicatorStyle:UIActivityIndicatorViewStyleGray];

[_homeCellImage sd_setImageWithURL:[NSURL URLWithString:[NSString stringWithFormat:@"%@%@",[dictionary objectForKey:@"user_image"],[QPCommonClass cropImageWithWidth:500 andHeight:500]]] placeholderImage:[UIImage imageNamed:@"defaultIcon"] options:SDWebImageRefreshCached];

[_qpQuestionImage setShowActivityIndicatorView:YES];

[_qpQuestionImage setIndicatorStyle:UIActivityIndicatorViewStyleGray];

[_qpQuestionImage sd_setImageWithURL:[NSURL URLWithString:[NSString stringWithFormat:@"%@%@",[dictionary objectForKey:@"image"],[QPCommonClass cropImageWithWidth:1400 andHeight:1200]]] placeholderImage:[UIImage imageNamed:@"question"] options:SDWebImageRefreshCached];

Answer 3

您必須在出隊后添加這兩行。

cell.layer.shouldRasterize = YES;
cell.layer.rasterizationScale = [UIScreen mainScreen].scale;