Android：更改方向后强制刷新屏幕

Question

I have an app utilizing Action Bar with Tab navigation which displays a listview via custom cursor adapter and then displays detail data when a listview item is clicked. I have implemented the logic to display dual pane when in landscape mode and parent/child views while in portrait mode.

My issue is that when I change orientation, my fragments stay the same until I select an item or change to a different tab.

IE: when I change from landscape to portrait, the dual pane displays in portrait mode.

My question is how do I force the fragment to reload? I have experimented with onStop() and onResume(), but I'm not sure what method to call from there?

Any help or suggestions would be greatly appreciated.

Here is my ListFragment:

public class ItemListFragment extends ListFragment {

// initialize variables
private boolean mDualPane;
private int mCurCheckPosition = 0;
private DataAdapter db;
private Cursor cursor;
private MyListAdapter items;

// methods  
@Override
public View onCreateView(LayoutInflater inflater, 
        ViewGroup container, Bundle savedInstanceState) { 
    return inflater.inflate(R.layout.fragment_layout, container, false);
}

@Override
public void onActivityCreated(Bundle savedState) {
    super.onActivityCreated(savedState);

    // create a database connection
    db = new DataAdapter(getActivity());
    db.open();
    cursor = db.getAllRecords();

    // get the filter EditText view
    filterText = (EditText) getActivity().findViewById(R.id.search_box);
    filterText.addTextChangedListener(filterTextWatcher);

    // set the parameters for the ListAdapter
    String[] from = new String[] { DataAdapter.KEY_TITLE };
    int[] to = new int[] {R.id.item_title }; 

    // Now create an array adapter and set it to display using our row
    items = new MyListAdapter(getActivity(), R.layout.item_cell, cursor, from, to);

    // get the listview
    ListView listview = getListView();
    listview.setAdapter(items);

    // check if we need dual pane
    mDualPane = isLandscape();

    if (savedState != null) {
        // Restore last state for checked position.
        mCurCheckPosition = savedState.getInt("curChoice", 0);
    }

    if (mDualPane) {
        // getListView().setChoiceMode(ListView.CHOICE_MODE_SINGLE);
        items.setSelectedPosition(mCurCheckPosition, cursor);
    }       
}

\\layout\\Fragment_layout.xml:

<?xml version="1.0" encoding="utf-8"?>

<ListView
    android:id="@android:id/list"
    android:layout_width="match_parent"
    android:layout_height="0dip"
    android:layout_weight="1" />

\\layout-land\\fragment_layout.xml:

<?xml version="1.0" encoding="utf-8"?>

<ListView
    android:id="@android:id/list"
    android:layout_width="match_parent"
    android:layout_height="0dip"
    android:layout_weight="1" />

<FrameLayout
    android:id="@+id/details"
    android:layout_width="0px"
    android:layout_height="match_parent"
    android:layout_weight="1" />

Answer 1

First of all you need some configurations on your manifest;

    <activity
        android:name="yourActivity"
        android:configChanges="orientation|screenSize"       
        android:screenOrientation="sensor" >
    </activity>

actually this congfiguration handles landscape and portrait mode automatically. But if you want to specific changes in your fragments, you can trigger fragment's methods from onConfigurationChanged method in your activity.

    public void onConfigurationChanged(Configuration newConfig) {
    super.onConfigurationChanged(newConfig);

    // Checks the orientation of the screen
    if (newConfig.orientation == Configuration.ORIENTATION_LANDSCAPE) {
        //TODO with Landscape
    } else if (newConfig.orientation == Configuration.ORIENTATION_PORTRAIT) {
        //TODO with Portrait
    }
}