Question

以下方法在我的iPhone 3S上运行时会导致滚动问题。我知道我们可以提高滚动的性能，但即使在网上搜索了很多东西并尝试了几件事之后也不知道怎么做。

我遇到过使单元格不透明和/或将表视图作为子视图来大大提高滚动性能，如果有人可以修改下面的代码或只是指出需要在下面的代码中更改的内容。我的代码如下。

// cell is created for each row of track.
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath 
{
    NSLog(@"tableView cellForRowAtIndexPath");


    static NSString *CellIdentifier = @"Cell";
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
    [CellIdentifier release];
    cell.accessoryView = nil;

    if (cell == nil)
    {
         cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle 
                                                        reuseIdentifier:CellIdentifier];
    }

     /** saving the data in Book structure.**/
     Book *aBook = [appDelegate.books objectAtIndex:indexPath.row];

     [cell.textLabel setText: aBook.name];

    // indexrow refers to each cell 
    temp =[appDelegate.tracklocation intValue];
    requesttemp =[appDelegate.requestlocation intValue];        

    // Coloring Code starts
    // indexPath starts from 0th cell that is why it is incremented by 1
    if(temp==(indexPath.row+1))
    { 
        NSLog(@"value of temp inside if is = %d",temp);
        NSLog(@"value of indexrow inside if is=%d",(indexPath.row+1));
        UIImageView *imageView1 = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"speaker.png"]];
        imageView1.backgroundColor = [ UIColor greenColor ];
        cell.contentView.backgroundColor = [ UIColor greenColor ];
        [cell.textLabel setBackgroundColor:[UIColor greenColor]];
        [cell.textLabel setTextColor:[UIColor blackColor]];
        [cell.detailTextLabel setBackgroundColor:[UIColor greenColor] ];
        [cell.detailTextLabel setTextColor:[UIColor blackColor] ];
        cell.accessoryView = imageView1;
        [imageView1 release];
    }
    else 
    {
        cell.contentView.backgroundColor = [ UIColor whiteColor ];
        [cell.textLabel setBackgroundColor:[UIColor whiteColor] ];
        [cell.textLabel setTextColor:[UIColor blackColor ]];
        [cell.detailTextLabel setBackgroundColor:[UIColor whiteColor]];
        [cell.detailTextLabel setTextColor:[UIColor grayColor] ];
    }

        while(requesttemp>temp)
        { 
            if (requesttemp==(indexPath.row+1))
            {
                if (colorflag==1)
                {
                    NSLog(@"value of request temp inside while is = %d",requesttemp);
                    NSLog(@"value of indexrow inside while is=%d",(indexPath.row+1));
                    cell.contentView.backgroundColor = [ UIColor blueColor ];
                    [cell.textLabel setBackgroundColor:[UIColor blueColor ]];
                    [cell.textLabel setTextColor:[UIColor whiteColor ]];
                    [cell.detailTextLabel setBackgroundColor:[UIColor blueColor] ];
                    [cell.detailTextLabel setTextColor:[UIColor whiteColor] ];
                }
            }
            requesttemp=requesttemp-1;
        }
    }    

    cell.detailTextLabel.text = abook.artist;

    cell.detailTextLabel.numberOfLines = 1;

     cell.detailTextLabel.lineBreakMode = UILineBreakModeWordWrap;
     NSLog(@"RootViewController cellForRowAtIndexPath %@ ",cell);

     return cell;
}

Answer 1

[cellIdentifier release] ?? 你不释放静电!! 您的单元重用可能因此失败。

UITableViewCell分配也没有自动释放。这应该会造成大量泄漏并最终减慢/崩溃应用程序。

这是泄漏+细胞重复使用失败的致命组合

希望这有帮助

在3GS上运行的iPhone应用程序中的滚动问题

1 个答案: