Android requestFeature() must be called before adding content报错

在Activity设置窗口没标题时用下面代码时报错：requestFeature() must be called before adding content

 protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,WindowManager.LayoutParams.FLAG_FULLSCREEN);
        setContentView(R.layout.activity_main);
        
    }

这是由于初始化时执行requestWindowFeature(Window.FEATURE_NO_TITLE)时需要在添加内容之前，网上的一些解决方案如下：

 protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        setContentView(R.layout.activity_main); //setContentView必须放在requestWindowFeature和getWindow().setFlags()中间
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,WindowManager.LayoutParams.FLAG_FULLSCREEN);
   
    }

OK，点击调试运行....结果依然报这个错，试一下把requestWindowFeature(Window.FEATURE_NO_TITLE)放在super.onCreate前面，问题解决，最终代码是这样的：

 protected void onCreate(Bundle savedInstanceState) {
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,WindowManager.LayoutParams.FLAG_FULLSCREEN);

    }