解决导航栏变黑色

Window window = getWindow();
    window.getDecorView()
            .setSystemUiVisibility(View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
                    | View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
                    | View.SYSTEM_UI_FLAG_LAYOUT_STABLE);
    window.setNavigationBarColor(Color.TRANSPARENT);

代码要在super.onCreate(savedInstanceState)执行之前调用

protected void onCreate(Bundle savedInstanceState) {
    Window window = getWindow();
    window.getDecorView()
            .setSystemUiVisibility(View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
                    | View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
                    | View.SYSTEM_UI_FLAG_LAYOUT_STABLE);
    window.setNavigationBarColor(Color.TRANSPARENT);
    
    super.onCreate(savedInstanceState);
}