Question

在我的应用中，我使用API从服务器获取图像。使用下面的代码，它按大小顺序获取图像，以更好的质量替换自己。

dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
    NSURL *imageURL = [NSURL URLWithString: [NSString stringWithFormat:@"%@", [[[self.information objectForKey:@"images"]objectForKey:@"normal"] description]]];
    NSData *imageData = [NSData dataWithContentsOfURL:imageURL];
    self.shotImage = [UIImage imageWithData:imageData];
    self.image.image = self.shotImage;
});

dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
    NSURL *imageURL = [NSURL URLWithString: [NSString stringWithFormat:@"%@", [[[self.information objectForKey:@"images"]objectForKey:@"hidpi"] description]]];
    NSData *imageData = [NSData dataWithContentsOfURL:imageURL];
    UIImage *image = [UIImage imageWithData:imageData];
    self.image.image = self.shotImage;
});

此外，如果你按下图像，那么你将获得另一个ViewController，其中图像是全屏的。

然而，即使我在点击之前等待高质量的加载，在PrepareForSegue方法中，它仍然只通过原始的低质量版本。

请参阅下面的PrepareForSegue代码

-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
    FullSizeImageViewController *vc = [segue destinationViewController];
    UIImage *img = [[UIImage alloc] init];
    img = self.shotImage;
    vc.shotImage = img;   
}

Answer 1

dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
    NSURL *imageURL = [NSURL URLWithString: [NSString stringWithFormat:@"%@", [[[self.information objectForKey:@"images"]objectForKey:@"hidpi"] description]]];
    NSData *imageData = [NSData dataWithContentsOfURL:imageURL];
    UIImage *image = [UIImage imageWithData:imageData];
    self.image.image = self.shotImage;
});

在此代码中，您似乎错过了这一行：

self.shotImage = [UIImage imageWithData:imageData];

iOS UIImage传递旧图像

1 个答案: