你可以通过使用Shader实现你的目标
ShapeDrawable.ShaderFactory sf = new ShapeDrawable.ShaderFactory() {
@Override
public Shader resize(int width, int height) {
return new LinearGradient(width/2, 0, width/2, height,
new int[]{0xff000000, 0xff42f448, 0xff000000},
new float[]{0, 0.3f, 1}, // start, center and end position
Shader.TileMode.CLAMP);
}
};
PaintDrawable pd = new PaintDrawable();
pd.setShape(new RectShape());
pd.setShaderFactory(sf);
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN) {
layout.setBackground(pd);
} else
layout.setBackgroundDrawable(pd);