最简单的沉浸式

getWindow().setStatusBarColor(Color.TRANSPARENT);
        getWindow().getDecorView().setSystemUiVisibility(View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN);

在Activity的setContentView之前调用这两句代码 apiLevel >= 21


//或者在setContentView之前调用
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,WindowManager.LayoutParams.FLAG_LAYOUT_IN_SCREEN);