为 iphone 应用程序的 UILabel 设置透明背景

我在 UITableView 中有一个 UILabel.这是我在 cellForRowAtIndexPath 中编写的代码

I have a UILabel in UITableView. Here is the code i have written in cellForRowAtIndexPath

    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
    if (cell == nil) {
        cell = [[[UITableViewCell alloc] initWithFrame:CGRectMake(30.0, 5.0, 250.0, 35.0) reuseIdentifier:CellIdentifier] autorelease];
    }   


    CGRect rect = CGRectMake(30.0, 5.0, 250.0, 35.0);
    UILabel *label = [[UILabel alloc] initWithFrame:rect];

    label.opaque = NO;  
    label.font = [UIFont systemFontOfSize:14];
    label.numberOfLines = 2;
    label.textAlignment = UITextAlignmentCenter;            
    label.textColor = [UIColor darkGrayColor];
    label.backgroundColor = [UIColor colorWithRed:0.0 green:0.0 blue:0.0 alpha:0.0];
    [label setText:@"Test Message"];    

    [cell addSubview:label];
    [label release];
    cell.backgroundColor = [UIColor colorWithRed:0.0 green:0.0 blue:0.0 alpha:0.0];
    cell.selectionStyle = UITableViewCellSelectionStyleNone;    

我的目的是将单元格和 UILabel 的背景设置为透明.

My intention was to set the background of cell and UILabel as transparent.

但是它不起作用.谁能告诉我我在这里缺少什么

But it is not working. can any one tell me what i am missing here

谢谢

桑迪普