iOS的表preVIEW图像发布 [英] iOS table preview image release

问题描述

我测试我的iPhone的RSS。它采用0笔尖文件。我会尽力为最佳，我可以来形容它，将张贴code如果需要，但我敢打赌，它的一个共同的解决方案，一个共同的现象。的问题是在一个tableviewcontroller，并将该溶液可能需要cellForRowAtIndexPath方法中实施。如果我向下滚动，preVIEW图像留在各自的点，直到异步加载队列该小区正确的图像。所以，如果我有数组项1的图像，我向下滚动到阵列项目20，对数组项1的图像将仍然存在，直到我的队列赶上并加载该图像。我怎样才能释放从细胞中，我没有观看图像？感谢您的时间。

下面是我的CellForRow ...

   - （UITableViewCell的*）的tableView：（UITableView的*）的tableView的cellForRowAtIndexPath：（NSIndexPath *）indexPath
{
静态的NSString * CellIdentifier = @细胞;
CustomCell *电池= [的tableView dequeueReusableCellWithIdentifier：CellIdentifier];
如果（细胞==零）{
    电池= [[CustomCell页头] initWithFrame：方法CGRectZero reuseIdentifier：CellIdentifier];
}
ArticleItem *对象= _objects [indexPath.row]
cell.pr​​imaryLabel.text = object.title;
cell.secondaryLabel.text = object.strippedDescription;
cell.pr​​imaryLabel.lineBreakMode = NSLineBreakByWordWrapping;
    cell.pr​​imaryLabel.numberOfLines = 0;
    cell.pr​​imaryLabel.lineBreakMode = NSLineBreakByWordWrapping;
    cell.secondaryLabel.numberOfLines = 0;//图像preVIEW装载异步发送队列...
dispatch_queue_t队列= dispatch_get_global_queue（DISPATCH_QUEUE_PRIORITY_HIGH，0ul）;
dispatch_async（队列，^ {    * UIImage的preVIEW =零;
    如果（object.iG =无）
    {
        preVIEW = [UIImage的imageNamed：@CellLogo.png];
    }
    其他
    {
        preVIEW = [UIImage的imageWithData：object.iG];
    }
    dispatch_sync（dispatch_get_main_queue（），^ {        [细胞myImageView] setImage：preVIEW]。
        [细胞setNeedsLayout]
    }）;
}）;
返回细胞;
}
 

如果你收集，我有一个ArticleItem类拉动图像URL，并把它们转化成数据，我有一个CustomCell类做什么其所谓。
    CustomCell.h
    @interface CustomCell：{的UITableViewCell
        * UIImageView的myImageView;
    }
    @属性（非原子，强）的UIImageView * myImageView;
    @结束
    ================================================== ===
    CustomCell.m

   - （ID）initWithFrame：方法（的CGRect）帧reuseIdentifier：（* NSString的）reuseIdentifier {
如果（自= [超级initWithFrame：方法框架reuseIdentifier：reuseIdentifier]）{
    //初始化code
            myImageView = [[UIImageView的页头]初始化];
    [self.contentView addSubview：myImageView];
}
返回自我;
}
 - （无效）{viewDidUnload
myImageView =零;
primaryLabel =零;
secondaryLabel =零;
}
 

解决方案

实施的UITableViewCell的子类中，为ImageView的属性。只要它得到从能见度远，它将被释放。描述只是概述，你可以自己根据需要滚动查看用法。

I'm testing an RSS on my iPhone. It uses 0 nib files. I'll try to describe it as best as I can, and will post code if its required, but I bet its a common phenomena with a common solution. The issue is in a tableviewcontroller, and the solution probably needs to be implemented in the CellForRowAtIndexPath method. If I scroll down, preview images stay in their respective spots until the async queue loads the correct image for that cell. So if I have an image for array item 1, and I scroll down to array item 20, the image for array item 1 will still be there until my queue catches up and loads that image. How can I release the images from cells that I am not viewing? Thank you for your time.

Here is my CellForRow...

-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = @"Cell";
CustomCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
    cell = [[CustomCell alloc] initWithFrame:CGRectZero reuseIdentifier:CellIdentifier];
}
ArticleItem *object = _objects[indexPath.row];
cell.primaryLabel.text = object.title;
cell.secondaryLabel.text = object.strippedDescription;
cell.primaryLabel.lineBreakMode = NSLineBreakByWordWrapping;
    cell.primaryLabel.numberOfLines = 0;
    cell.primaryLabel.lineBreakMode = NSLineBreakByWordWrapping;
    cell.secondaryLabel.numberOfLines = 0;

//Async dispatch queue for image preview loading...
dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0ul);
dispatch_async(queue, ^{ 

    UIImage *preview = nil;
    if (object.iG = nil)
    {
        preview = [UIImage imageNamed:@"CellLogo.png"];
    }
    else
    {
        preview = [UIImage imageWithData:object.iG];
    } 
    dispatch_sync(dispatch_get_main_queue(), ^{

        [[cell myImageView] setImage:preview];
        [cell setNeedsLayout];
    });
});
return cell;   
}

If you gather, I have an ArticleItem class which pulls the image URLS and turns them into data , and I have a CustomCell class which does what its called. CustomCell.h @interface CustomCell : UITableViewCell { UIImageView *myImageView; } @property(nonatomic,strong)UIImageView *myImageView; @end ===================================================== CustomCell.m

- (id)initWithFrame:(CGRect)frame reuseIdentifier:(NSString *)reuseIdentifier {
if (self = [super initWithFrame:frame reuseIdentifier:reuseIdentifier]) {
    // Initialization code
            myImageView = [[UIImageView alloc]init];


    [self.contentView addSubview:myImageView];       
}
return self;
}
-(void)viewDidUnload {
myImageView = nil;
primaryLabel = nil;
secondaryLabel = nil;
}

解决方案

Implement a subclass of UITableViewcell, make a property for imageview. As soon as it gets away from visibility, it will be released. Describing just the overview as you may yourself need to see the usage upon scrolling.

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