Android activity中单击返回键或home键彻底退出应用

    @Override
    public boolean onKeyDown(int keyCode, KeyEvent event) {
        if(keyCode == KeyEvent.KEYCODE_BACK||keyCode == KeyEvent.KEYCODE_HOME){
            finish();
        }
        return super.onKeyDown(keyCode, event);
    }
    @Override
    protected void onDestroy() {

        System.exit(0);
        super.onDestroy();
    }