使用sdwebimage在tableview中的动态图像高度 [英] Dynamic image height in tableview with using sdwebimage

问题描述

我想在表格视图中显示动态高度图像，图像来自url，所以我正在使用sdwebimage。
Sdwebimage在后台线程中设置图像。

I want dynamic height image show in tableview, image is come from url so I am using the sdwebimage. Sdwebimage set image in background thread.

[self.imageView sd_setImageWithURL:[NSURL URLWithString: encodedurl1]  completed:^(UIImage * _Nullable image, NSError * _Nullable error, SDImageCacheType cacheType, NSURL * _Nullable imageURL) {
  }];

我正在此线程中更新图像视图的约束高度。

I am update the constraint height of image view in this thread.

[self.imageView sd_setImageWithURL:[NSURL URLWithString: encodedurl1]  completed:^(UIImage * _Nullable image, NSError * _Nullable error, SDImageCacheType cacheType, NSURL * _Nullable imageURL) {
     CGFloat multiplier = (CGRectGetWidth(self.imageView.bounds) / image.size.width);
    [self.imageViewHeightConstraint setConstant:multiplier * image.size.height];
 }];

此代码对我有用，但是我在后台线程
中获得了图像大小花一点时间更新约束图像视图的高度

This code is helpful for me but I get image size in background thread So, I take a time to update the height of constraint image view

我正在搜索并仔细检查了最近两天。
这种类型的问题吸引了很多开发人员，但在堆栈溢出的任何问题中都没有答案。

I am search and goggling last 2 days. This type issue get many developer, but not answer in any question in stack overflow.

推荐答案

尝试使用此Helper方法

Try this Helper method which created for my project.

-(void)imageWithURL:(NSURL *)imageurl WithIndexPath:(NSIndexPath *)indexpath WithCallback:(void(^)(UIImage *downloadedImage,BOOL isCache , NSIndexPath *imageIndexPath))callback{
    if (![[SDWebImageManager sharedManager ]diskImageExistsForURL:imageurl]) {
        [[SDWebImageManager sharedManager]downloadImageWithURL:imageurl options:0 progress:nil completed:^(UIImage *image, NSError *error, SDImageCacheType cacheType, BOOL finished, NSURL *imageURL) {
            // resize image here
            callback(image , NO,indexpath);
        }];

    }
    else{
        UIImage *image = [[SDImageCache sharedImageCache] imageFromDiskCacheForKey:[imageurl absoluteString]] ;
        // resize image here
        callback(image, YES ,indexpath);
    }

}

在cellForRowAtIndexPath

dispatch_async( dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
                    [self imageWithURL:[NSURL URLWithString:objPreparations.strImageURL] WithIndexPath:indexPath WithCallback:^(UIImage *downloadedImage, BOOL isCache, NSIndexPath *imageIndexPath) {

                        if (downloadedImage) {
                            dispatch_async( dispatch_get_main_queue(), ^{
                                UITableViewCell  *existcell = [tableView cellForRowAtIndexPath:imageIndexPath];
                                if (existcell) {
                                    // assign image to cell here
                                    [tableView reloadRowsAtIndexPaths:@[imageIndexPath] withRowAnimation:UITableViewRowAnimationNone];
                                }
                            });
                        }
                    }];
                });

不要忘了

在viewDidLoad

In viewDidLoad

tblView.estimatedRowHeight = 44.0 ;
 tblView.rowHeight = UITableViewAutomaticDimension;

还要给imageview赋予top，bottom，lead，trailing约束和imageview大于等高约束

And also Give top,bottom,leading,trailing constraints to imageview and greater than equal height constraint to imageview

这篇关于使用sdwebimage在tableview中的动态图像高度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！