如何在android中将渐变效果放置在图像之上？

GradientDrawable gradientDrawable = new GradientDrawable(
    GradientDrawable.Orientation.LEFT_RIGHT,
    new int[]{Color.RED, Color.BLUE}
);

ImageView imageView = new ImageView(context);
imageView.setBackground(gradientDrawable);

ImageView overlayImageView = new ImageView(context);
overlayImageView.setImageResource(R.drawable.your_image);

FrameLayout frameLayout = new FrameLayout(context);
frameLayout.addView(imageView);
frameLayout.addView(overlayImageView);

yourLayout.addView(frameLayout);