Android去掉默认的标题栏

去掉默认的标题栏：在onCreate方法里添加supportRequestWindowFeature(Window.FEATURE_NO_TITLE);

@Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        supportRequestWindowFeature(Window.FEATURE_NO_TITLE);
        setContentView(R.layout.activity_main);
    }