ReactEditText.java 文件源码

private ReactViewBackgroundDrawable getOrCreateReactViewBackground() {
  if (mReactBackgroundDrawable == null) {
    mReactBackgroundDrawable = new ReactViewBackgroundDrawable();
    Drawable backgroundDrawable = getBackground();
    super.setBackground(null);  // required so that drawable callback is cleared before we add the
    // drawable back as a part of LayerDrawable
    if (backgroundDrawable == null) {
      super.setBackground(mReactBackgroundDrawable);
    } else {
      LayerDrawable layerDrawable =
          new LayerDrawable(new Drawable[]{mReactBackgroundDrawable, backgroundDrawable});
      super.setBackground(layerDrawable);
    }
  }
  return mReactBackgroundDrawable;
}