Add gradient color on every ca shapelayer

Question

I am trying to add gradient on ca shape layer its only giving gradient effect on current view frame if i am using it by adding masklayer it is not effecting on every layer seperately

here is my code:

 CAShapeLayer *gradientMask = [CAShapeLayer layer];
    gradientMask.fillColor = [[UIColor clearColor] CGColor];
    gradientMask.strokeColor = [[UIColor blackColor] CGColor];
    gradientMask.lineWidth = _borderStrokeWidth;
    gradientMask.frame = CGRectMake(0, 0, self.bounds.size.width, self.bounds.size.height);

    gradientMask.path = maskLayer.path;


    CAGradientLayer *gradientLayer = [CAGradientLayer layer];
    gradientLayer.locations = [NSArray arrayWithObjects:
                               [NSNumber numberWithFloat:0.8f],
                               [NSNumber numberWithFloat:1.0f],
                               nil];
    gradientLayer.startPoint = CGPointMake(0.5,1.0);
    gradientLayer.endPoint = CGPointMake(1.0,0.5);
    gradientLayer.frame = CGRectMake(0, 0, self.bounds.size.width, self.bounds.size.height);
     NSArray *colors = [NSArray arrayWithObjects:(id)[UIColor redColor].CGColor, (id)[UIColor greenColor].CGColor,(id)[UIColor blueColor].CGColor,(id)[UIColor yellowColor].CGColor, nil];
    gradientLayer.colors = colors;

    [gradientLayer setMask:gradientMask];
   // [gradientLayer setMask:shapeLayer];
    [self.layer addSublayer:gradientLayer];

kindly give suggestions