自定义UITableviewcell,选择单元格时仍显示CGGradient?

我正在使用一个自定义的tableview单元格(就像Tweetie的快速滚动) 我在上下文中添加了一个渐变,看起来很不错,但是当我选择单元格时,渐变仍然可见。我不知道如何删除梯度时,细胞被选中?有什么想法吗?

干杯

尼克

 - (void)drawContentView:(CGRect)r
{
 CGContextRef context = UIGraphicsGetCurrentContext();

 UIColor *backgroundColor = [UIColor whiteColor];
 UIColor *textColor = [UIColor blackColor];
 UIColor *dateColor = [UIColor colorWithRed:77.f/255.f green:103.f/255.f blue:155.f/255.f alpha:1];

 if(self.selected)
 {


  backgroundColor = [UIColor clearColor];
  textColor = [UIColor whiteColor];


 }
 [backgroundColor set];
 CGContextFillRect(context, r);

 //add gradient
 CGGradientRef myGradient;
 CGColorSpaceRef myColorspace;

 size_t num_locations = 2;
 CGFloat locations[2] = {0.0, 1.0};
 CGFloat components[8] = {0.9f, 0.9f, 0.9f, 0.7f, // Bottom Colour: Red, Green, Blue, Alpha.
  1.0f, 1.0f, 1.0f, 1.0}; // Top Colour: Red, Green, Blue, Alpha.

 myColorspace = CGColorSpaceCreateDeviceRGB();
 myGradient = CGGradientCreateWithColorComponents (myColorspace, components,
               locations, num_locations);

 CGColorSpaceRelease(myColorspace);

 CGPoint startPoint, endPoint;
 startPoint.x = 0;
 startPoint.y = self.frame.size.height;
 endPoint.x = 0;
 endPoint.y = self.frame.size.height-15; // just keep the gradient static size, never mind how big the cell is
 CGContextDrawLinearGradient (context, myGradient, startPoint, endPoint, 0); 
 CGGradientRelease(myGradient);

 //gradient end

    //rest of custom drawing goes here....

    }

我应该在if单元格中选择代码吗?