make radial gradient image

gistfile1.m

-(UIImage*)makeGradientImage{
    UIGraphicsBeginImageContextWithOptions(self.bounds.size, NO, 1.0f);
    CGContextRef context=UIGraphicsGetCurrentContext();
    CGContextSaveGState(context);
    
    CGGradientRef myGradient;
    CGColorSpaceRef myColorspace;
    size_t num_locations = 2;
    CGFloat locations[2] = { 0.2, 0.9};
    CGFloat components[8] = { 0.0,0.0,0.0, 0.0,  // Start color
        0.0,0.0,0.0,1.0}; // End color
    myColorspace = CGColorSpaceCreateDeviceRGB();
    myGradient = CGGradientCreateWithColorComponents (myColorspace, components,
                                                      locations, num_locations);
    myGradient = CGGradientCreateWithColorComponents (myColorspace, components,
                                                      locations, num_locations);
    CGPoint myStartPoint={self.bounds.size.width/2,self.bounds.size.height/2};
    CGFloat myStartRadius=0, myEndRadius=self.bounds.size.width*1.5;
    CGContextDrawRadialGradient (context, myGradient, myStartPoint,
                                 myStartRadius, myStartPoint, myEndRadius,
                                 kCGGradientDrawsAfterEndLocation);
    
    UIImage* image=UIGraphicsGetImageFromCurrentImageContext();
    CGContextRestoreGState(context);
    CGColorSpaceRelease(myColorspace);
    CGGradientRelease(myGradient);
    UIGraphicsEndImageContext();
    NSLog(@"image size:%@",NSStringFromCGSize(image.size));
    return image;
}