Android:getArguments()始终获取null值

时间:2014-06-06 01:13:28

标签: android null android-activity fragment

我是android的新手,我已经被困在这个问题中2天了。我的片段无法从我的活动中得到论据。这是我的活动代码。

private void CountUnreadNotifications() {
        Cursor unread = db.getUnread();
        Bundle bundle = new Bundle();
        String number = Integer.toString(unread.getCount());
        bundle.putString("noOfNotif", number);
        BottomFragment fragment = new BottomFragment();
        fragment.setArguments(bundle);
    }

我确信变量号不为空。这是片段中的代码。

@Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {

        String i = null;
        Bundle bundle = this.getArguments();
        if(bundle != null){
            i = bundle.getString("noOfNotif");
        }
        else {
             i = "0";
        }

        View view = inflater.inflate(R.layout.fragment_menu_page, container,
                false);

        txtnoNotif = (TextView) view.findViewById(R.id.txtnoNotif);     
        txtnoNotif.setText(i);

请有人帮我回答这个问题。谢谢。 这是我在Activity Oncreate中的代码

@Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.menu_page);

        mDB.Open();
        CountUnreadNotifications();
        viewFragment();

    }

查看片段方法。

private void viewFragment() {
        FragmentManager fm = getFragmentManager();
        FragmentTransaction ft = fm.beginTransaction();

        BottomFragment myFragment = new BottomFragment();
        ft.add(R.id.linearLayout, myFragment);
        ft.commit();
    }

1 个答案:

答案 0 :(得分:2)

您的CountUnreadNotifications()方法尚未完成 将其更改为如下并注释掉viewFragment()

private void CountUnreadNotifications() {
    Cursor unread = db.getUnread();
    Bundle bundle = new Bundle();
    String number = Integer.toString(unread.getCount());
    bundle.putString("noOfNotif", number);
    BottomFragment fragment = new BottomFragment();
    fragment.setArguments(bundle);
    FragmentTransaction trans = mManager.beginTransaction();
    trans.replace(R.id.fragment_container, fragment ); // change fragment_container to your container
    trans.commit(); 

    }

我的猜测是你试图在你的方法viewFragment()中转换到BottomFragment,你必须初始化BottomFragment fragment = new BottomFragment();因此失去了你的论点 请发布viewFragment();