samples/ApiDemos/src/com/example/android/apis/app/LoaderRetained.java - platform/development - Git at Google

 /*
  * Copyright (C) 2012 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 package com.example.android.apis.app;

 import com.example.android.apis.app.LoaderCursor.CursorLoaderListFragment.MySearchView;

 import android.app.Activity;
 import android.app.FragmentManager;
 import android.app.ListFragment;
 import android.app.LoaderManager;
 import android.content.Context;
 import android.content.CursorLoader;
 import android.content.Loader;
 import android.database.Cursor;
 import android.net.Uri;
 import android.os.Bundle;
 import android.provider.ContactsContract.Contacts;
 import android.text.TextUtils;
 import android.util.Log;
 import android.view.Menu;
 import android.view.MenuInflater;
 import android.view.MenuItem;
 import android.view.View;
 import android.widget.ListView;
 import android.widget.SearchView;
 import android.widget.SimpleCursorAdapter;
 import android.widget.SearchView.OnCloseListener;
 import android.widget.SearchView.OnQueryTextListener;

 /**
  * Demonstration of the use of a CursorLoader to load and display contacts
  * data in a fragment.
  */
 public class LoaderRetained extends Activity {

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

         FragmentManager fm = getFragmentManager();

         // Create the list fragment and add it as our sole content.
         if (fm.findFragmentById(android.R.id.content) == null) {
             CursorLoaderListFragment list = new CursorLoaderListFragment();
             fm.beginTransaction().add(android.R.id.content, list).commit();
         }
     }

 //BEGIN_INCLUDE(fragment_cursor)
     public static class CursorLoaderListFragment extends ListFragment
             implements OnQueryTextListener, OnCloseListener,
             LoaderManager.LoaderCallbacks<Cursor> {

         // This is the Adapter being used to display the list's data.
         SimpleCursorAdapter mAdapter;

         // The SearchView for doing filtering.
         SearchView mSearchView;

         // If non-null, this is the current filter the user has provided.
         String mCurFilter;

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

             // In this sample we are going to use a retained fragment.
             setRetainInstance(true);

             // Give some text to display if there is no data.  In a real
             // application this would come from a resource.
             setEmptyText("No phone numbers");

             // We have a menu item to show in action bar.
             setHasOptionsMenu(true);

             // Create an empty adapter we will use to display the loaded data.
             mAdapter = new SimpleCursorAdapter(getActivity(),
                     android.R.layout.simple_list_item_2, null,
                     new String[] { Contacts.DISPLAY_NAME, Contacts.CONTACT_STATUS },
                     new int[] { android.R.id.text1, android.R.id.text2 }, 0);
             setListAdapter(mAdapter);

             // Start out with a progress indicator.
             setListShown(false);

             // Prepare the loader.  Either re-connect with an existing one,
             // or start a new one.
             getLoaderManager().initLoader(0, null, this);
         }

         public static class MySearchView extends SearchView {
             public MySearchView(Context context) {
                 super(context);
             }

             // The normal SearchView doesn't clear its search text when
             // collapsed, so we will do this for it.
             @Override
             public void onActionViewCollapsed() {
                 setQuery("", false);
                 super.onActionViewCollapsed();
             }
         }

         @Override public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
             // Place an action bar item for searching.
             MenuItem item = menu.add("Search");
             item.setIcon(android.R.drawable.ic_menu_search);
             item.setShowAsAction(MenuItem.SHOW_AS_ACTION_IF_ROOM
                     | MenuItem.SHOW_AS_ACTION_COLLAPSE_ACTION_VIEW);
             mSearchView = new MySearchView(getActivity());
             mSearchView.setOnQueryTextListener(this);
             mSearchView.setOnCloseListener(this);
             mSearchView.setIconifiedByDefault(true);
             item.setActionView(mSearchView);
         }

         public boolean onQueryTextChange(String newText) {
             // Called when the action bar search text has changed.  Update
             // the search filter, and restart the loader to do a new query
             // with this filter.
             String newFilter = !TextUtils.isEmpty(newText) ? newText : null;
             // Don't do anything if the filter hasn't actually changed.
             // Prevents restarting the loader when restoring state.
             if (mCurFilter == null && newFilter == null) {
                 return true;
             }
             if (mCurFilter != null && mCurFilter.equals(newFilter)) {
                 return true;
             }
             mCurFilter = newFilter;
             getLoaderManager().restartLoader(0, null, this);
             return true;
         }

         @Override public boolean onQueryTextSubmit(String query) {
             // Don't care about this.
             return true;
         }

         @Override
         public boolean onClose() {
             if (!TextUtils.isEmpty(mSearchView.getQuery())) {
                 mSearchView.setQuery(null, true);
             }
             return true;
         }

         @Override public void onListItemClick(ListView l, View v, int position, long id) {
             // Insert desired behavior here.
             Log.i("FragmentComplexList", "Item clicked: " + id);
         }

         // These are the Contacts rows that we will retrieve.
         static final String[] CONTACTS_SUMMARY_PROJECTION = new String[] {
             Contacts._ID,
             Contacts.DISPLAY_NAME,
             Contacts.CONTACT_STATUS,
             Contacts.CONTACT_PRESENCE,
             Contacts.PHOTO_ID,
             Contacts.LOOKUP_KEY,
         };

         public Loader<Cursor> onCreateLoader(int id, Bundle args) {
             // This is called when a new Loader needs to be created.  This
             // sample only has one Loader, so we don't care about the ID.
             // First, pick the base URI to use depending on whether we are
             // currently filtering.
             Uri baseUri;
             if (mCurFilter != null) {
                 baseUri = Uri.withAppendedPath(Contacts.CONTENT_FILTER_URI,
                         Uri.encode(mCurFilter));
             } else {
                 baseUri = Contacts.CONTENT_URI;
             }

             // Now create and return a CursorLoader that will take care of
             // creating a Cursor for the data being displayed.
             String select = "((" + Contacts.DISPLAY_NAME + " NOTNULL) AND ("
                     + Contacts.HAS_PHONE_NUMBER + "=1) AND ("
                     + Contacts.DISPLAY_NAME + " != '' ))";
             return new CursorLoader(getActivity(), baseUri,
                     CONTACTS_SUMMARY_PROJECTION, select, null,
                     Contacts.DISPLAY_NAME + " COLLATE LOCALIZED ASC");
         }

         public void onLoadFinished(Loader<Cursor> loader, Cursor data) {
             // Swap the new cursor in.  (The framework will take care of closing the
             // old cursor once we return.)
             mAdapter.swapCursor(data);

             // The list should now be shown.
             if (isResumed()) {
                 setListShown(true);
             } else {
                 setListShownNoAnimation(true);
             }
         }

         public void onLoaderReset(Loader<Cursor> loader) {
             // This is called when the last Cursor provided to onLoadFinished()
             // above is about to be closed.  We need to make sure we are no
             // longer using it.
             mAdapter.swapCursor(null);
         }
     }
 //END_INCLUDE(fragment_cursor)
 }
	/*
	* Copyright (C) 2012 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	package com.example.android.apis.app;

	import com.example.android.apis.app.LoaderCursor.CursorLoaderListFragment.MySearchView;

	import android.app.Activity;
	import android.app.FragmentManager;
	import android.app.ListFragment;
	import android.app.LoaderManager;
	import android.content.Context;
	import android.content.CursorLoader;
	import android.content.Loader;
	import android.database.Cursor;
	import android.net.Uri;
	import android.os.Bundle;
	import android.provider.ContactsContract.Contacts;
	import android.text.TextUtils;
	import android.util.Log;
	import android.view.Menu;
	import android.view.MenuInflater;
	import android.view.MenuItem;
	import android.view.View;
	import android.widget.ListView;
	import android.widget.SearchView;
	import android.widget.SimpleCursorAdapter;
	import android.widget.SearchView.OnCloseListener;
	import android.widget.SearchView.OnQueryTextListener;

	/**
	* Demonstration of the use of a CursorLoader to load and display contacts
	* data in a fragment.
	*/
	public class LoaderRetained extends Activity {

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

	FragmentManager fm = getFragmentManager();

	// Create the list fragment and add it as our sole content.
	if (fm.findFragmentById(android.R.id.content) == null) {
	CursorLoaderListFragment list = new CursorLoaderListFragment();
	fm.beginTransaction().add(android.R.id.content, list).commit();
	}
	}

	//BEGIN_INCLUDE(fragment_cursor)
	public static class CursorLoaderListFragment extends ListFragment
	implements OnQueryTextListener, OnCloseListener,
	LoaderManager.LoaderCallbacks<Cursor> {

	// This is the Adapter being used to display the list's data.
	SimpleCursorAdapter mAdapter;

	// The SearchView for doing filtering.
	SearchView mSearchView;

	// If non-null, this is the current filter the user has provided.
	String mCurFilter;

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

	// In this sample we are going to use a retained fragment.
	setRetainInstance(true);

	// Give some text to display if there is no data. In a real
	// application this would come from a resource.
	setEmptyText("No phone numbers");

	// We have a menu item to show in action bar.
	setHasOptionsMenu(true);

	// Create an empty adapter we will use to display the loaded data.
	mAdapter = new SimpleCursorAdapter(getActivity(),
	android.R.layout.simple_list_item_2, null,
	new String[] { Contacts.DISPLAY_NAME, Contacts.CONTACT_STATUS },
	new int[] { android.R.id.text1, android.R.id.text2 }, 0);
	setListAdapter(mAdapter);

	// Start out with a progress indicator.
	setListShown(false);

	// Prepare the loader. Either re-connect with an existing one,
	// or start a new one.
	getLoaderManager().initLoader(0, null, this);
	}

	public static class MySearchView extends SearchView {
	public MySearchView(Context context) {
	super(context);
	}

	// The normal SearchView doesn't clear its search text when
	// collapsed, so we will do this for it.
	@Override
	public void onActionViewCollapsed() {
	setQuery("", false);
	super.onActionViewCollapsed();
	}
	}

	@Override public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
	// Place an action bar item for searching.
	MenuItem item = menu.add("Search");
	item.setIcon(android.R.drawable.ic_menu_search);
	item.setShowAsAction(MenuItem.SHOW_AS_ACTION_IF_ROOM
	\| MenuItem.SHOW_AS_ACTION_COLLAPSE_ACTION_VIEW);
	mSearchView = new MySearchView(getActivity());
	mSearchView.setOnQueryTextListener(this);
	mSearchView.setOnCloseListener(this);
	mSearchView.setIconifiedByDefault(true);
	item.setActionView(mSearchView);
	}

	public boolean onQueryTextChange(String newText) {
	// Called when the action bar search text has changed. Update
	// the search filter, and restart the loader to do a new query
	// with this filter.
	String newFilter = !TextUtils.isEmpty(newText) ? newText : null;
	// Don't do anything if the filter hasn't actually changed.
	// Prevents restarting the loader when restoring state.
	if (mCurFilter == null && newFilter == null) {
	return true;
	}
	if (mCurFilter != null && mCurFilter.equals(newFilter)) {
	return true;
	}
	mCurFilter = newFilter;
	getLoaderManager().restartLoader(0, null, this);
	return true;
	}

	@Override public boolean onQueryTextSubmit(String query) {
	// Don't care about this.
	return true;
	}

	@Override
	public boolean onClose() {
	if (!TextUtils.isEmpty(mSearchView.getQuery())) {
	mSearchView.setQuery(null, true);
	}
	return true;
	}

	@Override public void onListItemClick(ListView l, View v, int position, long id) {
	// Insert desired behavior here.
	Log.i("FragmentComplexList", "Item clicked: " + id);
	}

	// These are the Contacts rows that we will retrieve.
	static final String[] CONTACTS_SUMMARY_PROJECTION = new String[] {
	Contacts._ID,
	Contacts.DISPLAY_NAME,
	Contacts.CONTACT_STATUS,
	Contacts.CONTACT_PRESENCE,
	Contacts.PHOTO_ID,
	Contacts.LOOKUP_KEY,
	};

	public Loader<Cursor> onCreateLoader(int id, Bundle args) {
	// This is called when a new Loader needs to be created. This
	// sample only has one Loader, so we don't care about the ID.
	// First, pick the base URI to use depending on whether we are
	// currently filtering.
	Uri baseUri;
	if (mCurFilter != null) {
	baseUri = Uri.withAppendedPath(Contacts.CONTENT_FILTER_URI,
	Uri.encode(mCurFilter));
	} else {
	baseUri = Contacts.CONTENT_URI;
	}

	// Now create and return a CursorLoader that will take care of
	// creating a Cursor for the data being displayed.
	String select = "((" + Contacts.DISPLAY_NAME + " NOTNULL) AND ("
	+ Contacts.HAS_PHONE_NUMBER + "=1) AND ("
	+ Contacts.DISPLAY_NAME + " != '' ))";
	return new CursorLoader(getActivity(), baseUri,
	CONTACTS_SUMMARY_PROJECTION, select, null,
	Contacts.DISPLAY_NAME + " COLLATE LOCALIZED ASC");
	}

	public void onLoadFinished(Loader<Cursor> loader, Cursor data) {
	// Swap the new cursor in. (The framework will take care of closing the
	// old cursor once we return.)
	mAdapter.swapCursor(data);

	// The list should now be shown.
	if (isResumed()) {
	setListShown(true);
	} else {
	setListShownNoAnimation(true);
	}
	}

	public void onLoaderReset(Loader<Cursor> loader) {
	// This is called when the last Cursor provided to onLoadFinished()
	// above is about to be closed. We need to make sure we are no
	// longer using it.
	mAdapter.swapCursor(null);
	}
	}
	//END_INCLUDE(fragment_cursor)
	}