UITableViewCell背景视图/图像

Question

Where do I set backgroundImage of tableview cell in cellForRowAt.. And how do I do that ? This is how I did it and it kinda works, but I want to know is that right method for setting backgroundimage ( cell.backgroundView ) and is it right place inside if(cell==nil) or outside that "if".?

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {    
    static NSString *cellIdentifier = @"RootViewCellIdentifier";

    UITableViewCell *cell = [_tableView dequeueReusableCellWithIdentifier:cellIdentifier];
    if (cell == nil) {
        cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:cellIdentifier];

        cell.backgroundView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"image1.png"]];
    }

    return cell;
}

Answer 1

Used to do that, but nowadays I prefer willDisplayCell :

- (void)tableView:(UITableView *)tableView
  willDisplayCell:(UITableViewCell *)cell
  forRowAtIndexPath:(NSIndexPath *)indexPath
{
    cell.backgroundColor = [UIColor redColor];
}

Documentation says

A table view sends this message to its delegate just before it uses cell to draw a row, thereby permitting the delegate to customize the cell object before it is displayed . This method gives the delegate a chance to override state-based properties set earlier by the table view, such as selection and background color. After the delegate returns, the table view sets only the alpha and frame properties, and then only when animating rows as they slide in or out.

When using cellForRowAtIndexPath, there were some weird special cases, where cell customization just didn't work fully as I wanted. No such problems with willDisplayCell.

Answer 2

-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath  *)indexPath {  
[cell.imageview setImage:[UIImage imageNamed:@"image1.png"]];
   }
return cell;

}

Answer 3

try with this might be helpful...

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {    
    static NSString *cellIdentifier = @"RootViewCellIdentifier";

    UITableViewCell *cell = [_tableView dequeueReusableCellWithIdentifier:cellIdentifier];
    if (cell == nil) {
        cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:cellIdentifier];

         UIImageView *backimg = [[UIImageView alloc] init];
        backimg.frame = CGRectMake(0, 0, 320, 44);
        backimg.tag = 20;
        [cell.contentView addSubview:backimg];
    }
    UIImageView *imag = (UIImageView *)[cell.contentView viewWithTag:20];
    [imag setImage:[UIImage imageNamed:@"sky.png"]];
    return cell;
}

Answer 4

The best place to set a background view for a cell is the tableView:willDisplayCell:forRowAtIndexPath: method.

- (void)tableView:(UITableView *)tableView willDisplayCell:(UITableViewCell *)cell forRowAtIndexPath:(NSIndexPath *)indexPath
{
    cell.backgroundView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"image1.png"]];
}