Android example source code file (NotesList.java)

This example Android source code file (NotesList.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Android by Example" ^TM.

Java - Android tags/keywords

android, classcastexception, column_index_title, componentname, content, contextmenuinfo, cursor, intent, menuinflater, network, noteslist, override, projection, simplecursoradapter, string, tag, ui, uri, view, widget

The NotesList.java Android example source code

/*
 * Copyright (C) 2007 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.notepad;

import android.app.ListActivity;
import android.content.ComponentName;
import android.content.ContentUris;
import android.content.Intent;
import android.database.Cursor;
import android.net.Uri;
import android.os.Bundle;
import android.util.Log;
import android.view.ContextMenu;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.view.ContextMenu.ContextMenuInfo;
import android.widget.AdapterView;
import android.widget.ListView;
import android.widget.SimpleCursorAdapter;

import com.example.android.notepad.NotePad.NoteColumns;

/**
 * Displays a list of notes. Will display notes from the {@link Uri}
 * provided in the intent if there is one, otherwise defaults to displaying the
 * contents of the {@link NoteProvider}
 */
public class NotesList extends ListActivity {
    private static final String TAG = "NotesList";

    /**
     * The columns we are interested in from the database
     */
    private static final String[] PROJECTION = new String[] {
        NoteColumns._ID, // 0
        NoteColumns.TITLE, // 1
    };

    /** The index of the title column */
    private static final int COLUMN_INDEX_TITLE = 1;
    
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        setDefaultKeyMode(DEFAULT_KEYS_SHORTCUT);

        // If no data was given in the intent (because we were started
        // as a MAIN activity), then use our default content provider.
        Intent intent = getIntent();
        if (intent.getData() == null) {
            intent.setData(NoteColumns.CONTENT_URI);
        }

        // Inform the list we provide context menus for items
        getListView().setOnCreateContextMenuListener(this);
        
        // Perform a managed query. The Activity will handle closing and requerying the cursor
        // when needed.
        Cursor cursor = managedQuery(getIntent().getData(), PROJECTION, null, null,
                                        NoteColumns.DEFAULT_SORT_ORDER);

        // Used to map notes entries from the database to views
        SimpleCursorAdapter adapter = new SimpleCursorAdapter(this, R.layout.noteslist_item, cursor,
                new String[] { NoteColumns.TITLE }, new int[] { android.R.id.text1 });
        setListAdapter(adapter);
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate menu from XML resource
        MenuInflater inflater = getMenuInflater();
        inflater.inflate(R.menu.list_options_menu, menu);
        
        // Generate any additional actions that can be performed on the
        // overall list.  In a normal install, there are no additional
        // actions found here, but this allows other applications to extend
        // our menu with their own actions.
        Intent intent = new Intent(null, getIntent().getData());
        intent.addCategory(Intent.CATEGORY_ALTERNATIVE);
        menu.addIntentOptions(Menu.CATEGORY_ALTERNATIVE, 0, 0,
                new ComponentName(this, NotesList.class), null, intent, 0, null);

        return super.onCreateOptionsMenu(menu);
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {
        case R.id.menu_add:
            // Launch activity to insert a new item
            startActivity(new Intent(Intent.ACTION_INSERT, getIntent().getData()));
            return true;
        default:
            return super.onOptionsItemSelected(item);
        }
    }

    @Override
    public void onCreateContextMenu(ContextMenu menu, View view, ContextMenuInfo menuInfo) {
        AdapterView.AdapterContextMenuInfo info;
        try {
             info = (AdapterView.AdapterContextMenuInfo) menuInfo;
        } catch (ClassCastException e) {
            Log.e(TAG, "bad menuInfo", e);
            return;
        }

        Cursor cursor = (Cursor) getListAdapter().getItem(info.position);
        if (cursor == null) {
            // For some reason the requested item isn't available, do nothing
            return;
        }

        // Inflate menu from XML resource
        MenuInflater inflater = getMenuInflater();
        inflater.inflate(R.menu.list_context_menu, menu);
        
        // Set the context menu header
        menu.setHeaderTitle(cursor.getString(COLUMN_INDEX_TITLE));
        
        // Append to the
        // menu items for any other activities that can do stuff with it
        // as well.  This does a query on the system for any activities that
        // implement the ALTERNATIVE_ACTION for our data, adding a menu item
        // for each one that is found.
        Intent intent = new Intent(null, Uri.withAppendedPath(getIntent().getData(), 
                                        Integer.toString((int) info.id) ));
        intent.addCategory(Intent.CATEGORY_ALTERNATIVE);
        menu.addIntentOptions(Menu.CATEGORY_ALTERNATIVE, 0, 0,
                new ComponentName(this, NotesList.class), null, intent, 0, null);
    }
        
    @Override
    public boolean onContextItemSelected(MenuItem item) {
        AdapterView.AdapterContextMenuInfo info;
        try {
             info = (AdapterView.AdapterContextMenuInfo) item.getMenuInfo();
        } catch (ClassCastException e) {
            Log.e(TAG, "bad menuInfo", e);
            return false;
        }
        
        Uri noteUri = ContentUris.withAppendedId(getIntent().getData(), info.id);

        switch (item.getItemId()) {
        case R.id.context_open:
            // Launch activity to view/edit the currently selected item
            startActivity(new Intent(Intent.ACTION_EDIT, noteUri));
            return true;
        case R.id.context_delete:
            // Delete the note that the context menu is for
            getContentResolver().delete(noteUri, null, null);
            return true;
        default:
            return super.onContextItemSelected(item);
        }
    }

    @Override
    protected void onListItemClick(ListView l, View v, int position, long id) {
        Uri noteUri = ContentUris.withAppendedId(getIntent().getData(), id);
        
        String action = getIntent().getAction();
        if (Intent.ACTION_PICK.equals(action) || Intent.ACTION_GET_CONTENT.equals(action)) {
            // The caller is waiting for us to return a note selected by
            // the user.  The have clicked on one, so return it now.
            setResult(RESULT_OK, new Intent().setData(noteUri));
        } else {
            // Launch activity to view/edit the currently selected item
            startActivity(new Intent(Intent.ACTION_EDIT, noteUri));
        }
    }
}