Erase The Image

- (void)viewDidLoad
{
   [super viewDidLoad];
 drawImage = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"Picture 1.png"]];
 frontImage = [[UIImageView alloc] initWithFrame:CGRectMake(0.0f, 0.0f, 240.0f, 240.0f)];
 frontImage.image = [UIImage imageNamed:@"P1Mother0091.1.png"];
 frontImage.opaque = NO;
 [self.view addSubview:drawImage];
 [drawImage addSubview:frontImage];
 self.view.backgroundColor = [UIColor lightGrayColor];
 mouseMoved = 0;
 mouseSwiped = YES;
}

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
 
 
 UITouch *touch = [touches anyObject];
 
 if ([touch tapCount] == 2) {
  
  return;
 }

 lastPoint = [touch locationInView:frontImage];
 lastPoint.y -= 20;

}


- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
 
 
 UITouch *touch = [touches anyObject]; 
 CGPoint currentPoint = [touch locationInView:frontImage];
 currentPoint.y -= 20;
 
//erase part
 if(mouseSwiped)
 {
 
 //**************Working Code*************// 
  
 
 UIGraphicsBeginImageContext(frontImage.frame.size);
 [frontImage.image drawInRect:CGRectMake(0, 0, frontImage.frame.size.width, frontImage.frame.size.height)];
 CGContextSetLineCap(UIGraphicsGetCurrentContext(),kCGImageAlphaNone); //kCGImageAlphaPremultipliedLast);
 CGContextSetLineWidth(UIGraphicsGetCurrentContext(), 10);
 CGContextSetRGBStrokeColor(UIGraphicsGetCurrentContext(), 1, 0, 0, 10);
 CGContextBeginPath(UIGraphicsGetCurrentContext());
 CGContextMoveToPoint(UIGraphicsGetCurrentContext(), lastPoint.x, lastPoint.y);
 CGContextClearRect (UIGraphicsGetCurrentContext(), CGRectMake(lastPoint.x, lastPoint.y, 10, 10));
 CGContextStrokePath(UIGraphicsGetCurrentContext());
 frontImage.image = UIGraphicsGetImageFromCurrentImageContext();
 UIGraphicsEndImageContext();
 
   
 lastPoint = currentPoint;
  
 mouseMoved++;
 
 if (mouseMoved == 10)
 {
  mouseMoved = 0;
 }
 }

//Unerase part
 if(!mouseSwiped)
  
 {
  
  //UIGraphicsBeginImageContext(self.view.frame.size);
  UIGraphicsBeginImageContext(frontImage.frame.size);
  [frontImage.image drawInRect:CGRectMake(0, 0, frontImage.frame.size.width, frontImage.frame.size.height)];
  //brushContext = CGBitmapContextCreate(brushData, width, width, 8, width * 4, CGImageGetColorSpace(brushImage), kCGImageAlphaPremultipliedLast);
  CGContextSetLineCap(UIGraphicsGetCurrentContext(),kCGImageAlphaNone); //kCGImageAlphaPremultipliedLast);
  //kCGImageAlphaPremultipliedLast
  CGContextSetLineWidth(UIGraphicsGetCurrentContext(), 10);
  //CGContextSetRGBStrokeColor(UIGraphicsGetCurrentContext(), 0.0, 1.0, 0.0, 1.0);
  CGContextSetRGBStrokeColor(UIGraphicsGetCurrentContext(), 1, 0, 0, 10);
  CGContextBeginPath(UIGraphicsGetCurrentContext());
  CGContextMoveToPoint(UIGraphicsGetCurrentContext(), lastPoint.x, lastPoint.y);
  //CGContextRestoreGState(UIGraphicsGetCurrentContext());
  CGContextRetain(UIGraphicsGetCurrentContext());
  //CGContextStrokePath(UIGraphicsGetCurrentContext());
  frontImage.image = UIGraphicsGetImageFromCurrentImageContext();
  UIGraphicsEndImageContext();
  
 }
}

- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
 
 UITouch *touch = [touches anyObject];
 
 if ([touch tapCount] == 2) {
  //drawImage.image = nil;
  return;
 }
 
 // Unerase part
 if(!mouseSwiped)
 
 {

  //UIGraphicsBeginImageContext(self.view.frame.size);
  UIGraphicsBeginImageContext(frontImage.frame.size);
  [frontImage.image drawInRect:CGRectMake(0, 0, frontImage.frame.size.width, frontImage.frame.size.height)];
  //brushContext = CGBitmapContextCreate(brushData, width, width, 8, width * 4, CGImageGetColorSpace(brushImage), kCGImageAlphaPremultipliedLast);
  CGContextSetLineCap(UIGraphicsGetCurrentContext(),kCGImageAlphaNone); //kCGImageAlphaPremultipliedLast);
  //kCGImageAlphaPremultipliedLast
  CGContextSetLineWidth(UIGraphicsGetCurrentContext(), 10);
  //CGContextSetRGBStrokeColor(UIGraphicsGetCurrentContext(), 0.0, 1.0, 0.0, 1.0);
  CGContextSetRGBStrokeColor(UIGraphicsGetCurrentContext(), 1, 0, 0, 10);
  CGContextBeginPath(UIGraphicsGetCurrentContext());
  CGContextMoveToPoint(UIGraphicsGetCurrentContext(), lastPoint.x, lastPoint.y);
  //CGContextStrokePath(UIGraphicsGetCurrentContext());
  frontImage.image = UIGraphicsGetImageFromCurrentImageContext();
  UIGraphicsEndImageContext();
  
 }
}