Android设置全屏无效

package com.example.administrator.myapplication;

import android.content.pm.ActivityInfo;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.WindowManager;

public class MainActivity extends AppCompatActivity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        CustomView customView = new CustomView(this);
        setContentView(customView);
    }

    @Override
    protected void onResume() {
        super.onResume();
        if (getRequestedOrientation() != ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE) {
            setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
        }
    }

    public void setFullScreen(boolean isFullScreen) {
        setFullScreen(true);
        if (isFullScreen) {
            getWindow().addFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN);
            getWindow().clearFlags(WindowManager.LayoutParams.FLAG_FORCE_NOT_FULLSCREEN);
        } else {
            getWindow().addFlags(WindowManager.LayoutParams.FLAG_FORCE_NOT_FULLSCREEN);
        }
    }
}

无限递归？