What is the most efficient way to ensure content in cell are not re-used incorrectly

I am trying to add youtube videos to my UITableView via the following code. The trouble I had was the fact that the cell was being reused and the UIWebviews were also being reused causing the wrong videos to appear in the wrong cells.

I tried to resolve this issue by explicitly removing the UIWebview from superview before I set the video and also if the cell does not contain a youtube video.

But this seems rather expensive and inefficient. Can anyone advise me on a more efficient way of doing this so that the webview (containing the video) does not get reused in the wrong cells?

Code snippet from "cellforRowAtIndexPath":

//Re-create a UIWebview for youtube video everytime the cell is loaded
UIWebView *thisYouTubeVideo = [[UIWebView alloc]init];

//Check if this cell contains a youtube video
if (self.youtube_url !=nil) 
{
    //This is the first time I explicitly remove the UIWebview from cell's contentview
    for (UIView *subview in [self.contentView subviews]) {
        if ([subview isKindOfClass:[UIWebView class]]) {
            [subview removeFromSuperview];
        }
    }

    //This is just to set the frame of the UIWebview
    thisYouTubeVideo.frame = CGRectMake(CELL_TEXT_LEFT_MARGIN, currentYAxisValue, 240, 240);

    //Key for caching
    NSString *videokey=[NSString stringWithFormat:@"%@",self.answerForCell.youtube_url];

    //Check if webview has been created before, just load it from the dictionary (cache)
    if([self.youtubeVideoCache objectForKey:videokey]) {
        thisYouTubeVideo = [[self.youtubeVideoCache objectForKey:videokey]reta开发者_运维知识库in];                        
    }
    else
    {
        //If webview does not exist in cache, load the url to webview and store in cache
        NSString * videoHTML = [self embedYouTube:self.answerForCell.youtube_url frame:CGRectMake(CELL_TEXT_LEFT_MARGIN, currentYAxisValue, 240, 240)];
        [thisYouTubeVideo loadHTMLString:videoHTML baseURL:nil];

        [self.youtubeVideoCache setObject:thisYouTubeVideo forKey:videokey]; //Save webview in dictionary

    }

    //add the uiwebview to the cell's content view
    [self.contentView addSubview:thisYouTubeVideo];
    [thisYouTubeVideo release];

}
else
{
    //If the cell DOES not contain a youtube video, do the following
    thisYouTubeVideo.frame = CGRectZero;

    //This is the second time I am explicitly removing the webview from cell's content view
    for (UIView *subview in [self.contentView subviews]) {
        if ([subview isKindOfClass:[UIWebView class]]) {
            [subview removeFromSuperview];
        }
    }
}

Use your videoKey as the cell identifier

[tableView dequeueReusableCellWithIdentifier:videoKey],

but keep in mind that this will impact on memory usage, because you do not reuse the allocated cells any more.