Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
461 views
in Technique[技术] by (71.8m points)

android - Implementing action bar tabs with fragments

So recently I needed to implement action bar tabs that would swap out the current fragment with a new fragment. Despite hours of intensive searching I was unable to find a clear solution, so I thought I would present how I solved the problem here. Two of the fragments contained list views, which turned out to be a major complicating factor.

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Reply

0 votes
by (71.8m points)

First create an Activity to which you want to attach the fragments. In the XML file for that Activity add a linear layout like so:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context=".WoodenSideProject" >
<LinearLayout
    android:id="@+id/fragment_placeholder"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >
</LinearLayout>   

Do not add anything else to the XML file. Not even the tab host that is preloaded with Eclipse.

Next create your fragments. First build the UI for your fragment how you want it using the fragment's XML file. I will show how to create a fragment with a List View:

public class Fragment1Name extends Fragment
{
public static String TAG="DirectionsFragment";
private String[] list_items = {"Put the list of Strings you want here"};
ListView lView1;
/*@Override
public void onActivityCreated(Bundle savedInstanceState)
{
    super.onActivityCreated(savedInstanceState);
    ArrayAdapter<String> adapter = new ArrayAdapter<String>(getActivity(),
            android.R.layout.simple_list_item_1, list_items);
        setListAdapter(adapter);
}*/

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    View view = inflater.inflate(R.layout.fragment_XML_title, container, false);
    createListView(view);
    // Inflate the layout for this fragment
    return view;
}

private void createListView(View view)
{
    lView1 = (ListView) view.findViewById(R.id.ListViewID);
    //Set option as Multiple Choice. So that user can able to select more the one option from list
    lView1.setAdapter(new ArrayAdapter<String>(getActivity(),
    android.R.layout.simple_list_item_1, list_items));
}
}

Some people suggest extending ListFragment for a fragment that uses a List View. My experience has been that is more trouble than it's worth.

Set up the Activity's java file as follows:

public class ActivityName extends FragmentActivity {
public static Context appContext;

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

ActionBar actionBar = getActionBar();
actionBar.setDisplayHomeAsUpEnabled(true);
actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
setTitle("WoodenSideProject");

ActionBar.Tab tab1 = actionBar.newTab().setText("Tab1");
ActionBar.Tab tab2 = actionBar.newTab().setText("Tab2");
ActionBar.Tab tab3 = actionBar.newTab().setText("Tab3");

Fragment Fragment1Name = new Fragment1Name();
Fragment Fragment2Name = new Fragment2Name();
Fragment Fragment3Name = new Fragment3Name();

tab1.setTabListener(new MyTabsListener(Fragment1Name));
tab2.setTabListener(new MyTabsListener(Fragment2Name));
tab3.setTabListener(new MyTabsListener(Fragment3Name));

actionBar.addTab(tab1);
actionBar.addTab(tab2);
actionBar.addTab(tab3);
}

Within the same Activity create the following class:

class MyTabsListener implements ActionBar.TabListener {
public Fragment fragment;

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

@Override
public void onTabReselected(Tab tab, FragmentTransaction ft) {
    //do what you want when tab is reselected, I do nothing
}

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

@Override
public void onTabUnselected(Tab tab, FragmentTransaction ft) {
    ft.remove(fragment);
}
}

I don't know if others have had as much trouble as I implementing action bar tabs with fragments, but if they are I hope this helps. Any suggestions for better implementations would be greatly appreciated.


与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
OGeek|极客中国-欢迎来到极客的世界,一个免费开放的程序员编程交流平台!开放,进步,分享!让技术改变生活,让极客改变未来! Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...