android的新手，如何为片段内的元素初始化事件处理程序

Question

(Disclaimer: pretty new to android) So I am trying to make a tabbed application using Android Studio, and following examples online I have been able to use the actionbar to setup 2 tabs and fragments like so:

in MainActivity.java

    ActionBar bar = getActionBar();
    bar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
    bar.setTitle("My App Test");

    Tab tabSearch = bar.newTab().setText("Search").setIcon(android.R.drawable.ic_menu_search);
    Tab tabReport = bar.newTab().setText("Report").setIcon(android.R.drawable.ic_menu_report_image);

    Fragment stfrag = new SearchTabFragment();
    Fragment rptfrag = new ReportFragment();

    tabSearch.setTabListener(new MyTabsListener(stfrag));
    tabReport.setTabListener(new MyTabsListener(rptfrag));


    bar.addTab(tabSearch);
    bar.addTab(tabReport);

in ReportFragment/SearchTabFragment .java

public class SearchTabFragment extends Fragment {
    public View onCreateView(LayoutInflater inflater,ViewGroup container, Bundle savedInstanceState){

         return inflater.inflate(R.layout.fragment_1,container,false);

    }
 }

I basically just copied the example for the ActionBar listener directly from the tutorial I found:

class MyTabsListener implements ActionBar.TabListener {
    public Fragment fragment;

    public MyTabsListener(Fragment fragment){
        this.fragment = fragment;
    };

    @Override
    public void onTabSelected(Tab tab, FragmentTransaction ft){
        ft.replace(R.id.wrap,fragment);
    }

    @Override
    public void onTabUnselected(Tab tab, FragmentTransaction ft){

    }

    @Override
    public void onTabReselected(Tab tab, FragmentTransaction ft){

    }


}

Now my question is, how do I attach eventHandlers to the elements defined in my fragments.xml? Previously in a "Single Activity" application I played with I just put it in the main java file right after the onCreate event. Eg:

    @Override
    protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    (TextView) tv = (TextView) findViewByid(R.id.textviewidhere);
    //now I attach the handlers as I need

Thanks in advance! (edited for clarity)

Answer 1

You should probably read a little bit about fragments . You need to override onViewCreated and "catch" views there:

 public class MyFragment extends Fragment {
    View rootView;
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        rootView = inflater.inflate(R.layout.my_fragment, container,
                false);
        return rootView;

    }

//and you use rootView to call findViewById
    @Override
    public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {
        super.onViewCreated(view, savedInstanceState);
        Button myButton = (Button) rootView.findViewById(R.id.mybutton);
        //or you can set some other listener, or "catch" some different view -checkbox,          //textview etc
        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                //do something you want
            }
        });
    }

Answer 2

Example :

public class SearchTabFragment extends Fragment {
public View onCreateView(LayoutInflater inflater,ViewGroup container, Bundle savedInstanceState){

     View root = inflater.inflate(R.layout.fragment_1,container,false);
     TextView text = (TextView)root.findViewById(R.id.mybutton);

    return root;
 }

}

this will let use the TextView inside the fragment.

Answer 3

Modifed code lifted straight from the docs :

Scenario:

Let us say you have a Fragment with a button inside it. You would like to attach the activity as the event listener to that button inside fragment. Then,

public static class ButtonFragment extends Fragment implements OnClickListener {

    private OnClickListener mListener;

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

        // inflate the corresponding fragment XML
        View v = inflater.inflate(R.layout.example_fragment, container, false);

        // grab the button and attach this fragment as its listener
        ((Button)v.findViewById(R.id.btn)).setOnClickListener(this);

        return v;
    }

    @Override
    public void onAttach(Activity activity) {
        super.onAttach(activity);

        try {

            // once this fragment is attached to its activity, check to see
            // if it implements OnClickListener
            mListener = (OnClickListener) activity;

        } catch (ClassCastException e) {
            throw new ClassCastException(activity.toString() + " doesn't implement OnClickListener");
        }
    }

    ...
    public void onClick(View v) {
        if(mListener){
            // once the button inside fragment is clicked,
            // notify the activity about the same
            mListener.onClickListener(v);
        }
    }


}