CommentListItemBackgroundFactory.java 文件源码

protected Drawable makeDefaultBackground() {
    PaintDrawable shadow = new PaintDrawable(bottomColor);
    PaintDrawable highlight = new PaintDrawable(topColor);
    PaintDrawable surface = new PaintDrawable(bgColor);
    LayerDrawable layers = new LayerDrawable(new Drawable[] {shadow, highlight, surface});

    layers.setLayerInset(0, 0, 0, 0, 0);
    layers.setLayerInset(1, 0, 0, 0, 1);
    layers.setLayerInset(2, 0, 1, 0, 1);

    return layers;
}