@SuppressWarnings("deprecation")
    public void setNavigationBarTintDrawable(Drawable drawable) {
        if (mNavBarAvailable) {
            mNavBarTintView.setBackgroundDrawable(drawable);
        }
    }
Apply the specified drawable to the system navigation bar.

@param drawable The drawable to use as the background, or null to remove it.
app/src/main/java/com/zhao/myreader/util/SystemBarTintManager.java