Question

我在单个UITableView中制作两个自定义单元格并显示奇数偶数顺序，但是当我滚动UITableView时，所有图像和计划数据颜色将随机变化，并且将显示重复数据，但名称，exp。，pri-zone和rate在字符串中它们都显示正确，只有日程文本的图像和颜色会改变。

    - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:  (NSIndexPath *)indexPath
   {

if (indexPath.row % 2 == 0) {

    static NSString *cellIdentifier=@"MyCustomCell";
 TableViewCell *cell=[tblResponseData dequeueReusableCellWithIdentifier:cellIdentifier];

    if (cell == nil)
    {
        cell = [[TableViewCell alloc] initWithStyle:UITableViewCellStyleValue1      
     reuseIdentifier:cellIdentifier];
    }
    NSString *imgPath=[[arrData objectAtIndex:indexPath.row]valueForKey:@"Pic"];
    // NSString *imgPath=[[appDelegate.arrData  
    objectAtIndex:indexPath.row]valueForKey:@"image"];
    NSURL *url = [NSURL URLWithString:[imgPath 
     stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding]];
        NSString *schedule =[[arrData objectAtIndex:indexPath.row]valueForKey:@"Schedule"];

        NSArray *strings = [schedule componentsSeparatedByString:@","];


    //NSURL *url = [NSURL URLWithString:url];
    [NSURLConnection sendAsynchronousRequest:[NSURLRequest requestWithURL:url]
                                       queue:[NSOperationQueue currentQueue]
                           completionHandler:^(NSURLResponse * resp, NSData * data, NSError  
       * error)
     {
         if(error == NULL){
             // here is our image
             UIImage *image = [UIImage imageWithData:data];
             cell.imgThumbnail.image=image;
         }
         else{
             cell.imgThumbnail.image=[UIImage imageNamed:@"no preview 2.jpeg"];
         }
     }];



    for (NSString *item in strings)
    {
        if ([item isEqualToString:@"Su"]) {
            cell.lblsu.textColor = [UIColor greenColor];
        }else if ([item isEqualToString:@"Tu"]){
            cell.lblt.textColor = [UIColor greenColor];
        }else if ([item isEqualToString:@"Th"]){
            cell.lblth.textColor = [UIColor greenColor];
        }
        else if ([item isEqualToString:@"M"]){
            cell.lblm.textColor = [UIColor greenColor];
        }
        else if ([item isEqualToString:@"F"]){
            cell.lblf.textColor = [UIColor greenColor];
        }
        else if ([item isEqualToString:@"S"]){
            cell.lbls.textColor = [UIColor greenColor];
        }
        else if ([item isEqualToString:@"W"]){
            cell.lblw.textColor = [UIColor greenColor];
        }
    }
    cell.lblname.text = [[arrData objectAtIndex:indexPath.row] valueForKey:@"Worker Name"];
    cell.lblexperience.text=[[arrData o
   bjectAtIndex:indexPath.row]valueForKey:@"Experience"];
    cell.lblprizone.text=[[arrData objectAtIndex:indexPath.row]valueForKey:@"Primary 
     Zone"];
        cell.lblrate.text=[[arrData objectAtIndex:indexPath.row]valueForKey:@"Rate"];

    return cell;

   } else {
    static NSString *cellIdentifier1=@"MyCustomCell1";


    TableViewCell *cell1=[tblResponseData d
     equeueReusableCellWithIdentifier:cellIdentifier1];
    if (cell1 == nil)
    {
        cell1 = [[TableViewCell alloc] initWithStyle:UITableViewCellStyleValue1 
     reuseIdentifier:cellIdentifier1];
    }

    NSString *imgPath=[[arrData objectAtIndex:indexPath.row]valueForKey:@"Pic"];
    // NSString *imgPath=[[appDelegate.arrData 
   objectAtIndex:indexPath.row]valueForKey:@"image"];
    NSURL *url = [NSURL URLWithString:[imgPath      
    stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding]];


    //NSURL *url = [NSURL URLWithString:url];
    [NSURLConnection sendAsynchronousRequest:[NSURLRequest requestWithURL:url]
                                       queue:[NSOperationQueue currentQueue]
                           completionHandler:^(NSURLResponse * resp, NSData * data, NSError 
     * error)
     {
         if(error == NULL){
             // here is our image
             UIImage *image = [UIImage imageWithData:data];
             cell1.imgThumbnail.image=image;
         }
         else{
             cell1.imgThumbnail.image=[UIImage imageNamed:@"no preview 2.jpeg"];
         }
     }];
    // NSURL *imageUrl = [NSURL URLWithString:imgPath];
    //   NSData *imageData = [NSData dataWithContentsOfURL:url];
    //   UIImage *image=[[UIImage alloc]initWithData:imageData];
    // cell.imgThumbnail.image=image;

    NSString *schedule =[[arrData objectAtIndex:indexPath.row]valueForKey:@"Schedule"];

    NSArray *strings = [schedule componentsSeparatedByString:@","];
    for (NSString *item in strings)
    {
        if ([item isEqualToString:@"Su"]) {
            cell1.lblsu.textColor = [UIColor greenColor];
        }else if ([item isEqualToString:@"Tu"]){
            cell1.lblt.textColor = [UIColor greenColor];
        }else if ([item isEqualToString:@"Th"]){
            cell1.lblth.textColor = [UIColor greenColor];
        }
        else if ([item isEqualToString:@"M"]){
            cell1.lblm.textColor = [UIColor greenColor];
        }
        else if ([item isEqualToString:@"F"]){
            cell1.lblf.textColor = [UIColor greenColor];
        }
        else if ([item isEqualToString:@"S"]){
            cell1.lbls.textColor = [UIColor greenColor];
        }
        else if ([item isEqualToString:@"W"]){
            cell1.lblw.textColor = [UIColor greenColor];
        }
    }

    cell1.lblname.text = [[arrData objectAtIndex:indexPath.row] valueForKey:@"Worker N
     ame"];
    cell1.lblexperience.text=[[arrData    
      objectAtIndex:indexPath.row]valueForKey:@"Experience"];
    cell1.lblprizone.text=[[arrData objectAtIndex:indexPath.row]valueForKey:@"Primary 
    Zone"];


    cell1.lblrate.text=[[arrData objectAtIndex:indexPath.row]valueForKey:@"Rate"];
    return cell1;
  }

       }

Answer 1

我认为可能是因为您按NSURLConnection sendAsynchronousRequest加载了图片。因为completitionhandler不是立即调用的，而是在将数据返回给请求时。因此，在加载单元格之后，图像将被设置为。尝试替换

[NSURLConnection sendAsynchronousRequest:[NSURLRequest requestWithURL:url] queue:[NSOperationQueue currentQueue] completionHandler:^(NSURLResponse * resp, NSData * data, NSError * error) { if(error == NULL){ // here is our image UIImage *image = [UIImage imageWithData:data]; cell1.imgThumbnail.image=image; } else{ cell1.imgThumbnail.image=[UIImage imageNamed:@"no preview 2.jpeg"]; } }];

使用代码将imgThumbnail.image设置为项目中的图像，并查看是否仍然可以更改单元格。

Answer 2

问题：您正在使用dequeueReusableCellWithIdentifier，因此在滚动tableview时会重复使用相同的单元格，并且您在该单元格中发送AsynchronousRequest，以便我们在另一个单元格上接收先前发送的单元格响应，以便它显示出不同的结果。

例如：您发送请求的单元格2，然后您滚动表格视图，以便在单元格10重新使用相同的单元格时，您将收到单元格2发送请求的响应该图像（响应数据）显示在单元格10中。

解决方案：以单独的方法发送请求并将图像保存在数组或字典中，然后根据收到的响应重新加载相应的单元格。

例如： EGOImageView正在异步发送请求并保存在缓存中并在收到响应后显示请检查一次

Answer 3

尝试这个，用于从webservices加载图像。

 NSString *imgUrl = [[arrCategoryDetails objectAtIndex:indexPath.row]valueForKey:@"Image"];

dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
    NSData *imgData = [NSData dataWithContentsOfURL:[NSURL URLWithString:imgUrl]];
    if (imgData) {
        UIImage *image = [UIImage imageWithData:imgData];
        if (image) {
            dispatch_async(dispatch_get_main_queue(), ^{
                CategoryDetailsTableCell *updateCell = (id)[tableView cellForRowAtIndexPath:indexPath];
                if (updateCell)
                    updateCell.imgForCategoryDetailCell.image = image;
            });
        }
    }
});

滚动tableview时ios tableview图像加载重复

3 个答案: