Android example source code file (WikiNotes.java)

This example Android source code file (WikiNotes.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, content, cursor, delete_id, edit_id, email_id, failed, home_id, list_id, override, string, textview, ui, uri, util, utils, view, wiki_word_matcher, wikiactivityhelper, wikinotes

The WikiNotes.java Android example source code

/*
 * Copyright (C) 2008 Google Inc.
 * 
 * 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.google.android.wikinotes;

import java.util.regex.Pattern;

import android.app.Activity;
import android.content.ContentUris;
import android.content.ContentValues;
import android.content.Intent;
import android.database.Cursor;
import android.net.Uri;
import android.os.Bundle;
import android.text.util.Linkify;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.TextView;

import com.google.android.wikinotes.db.WikiNote;

/**
 * The WikiNotes activity is the default handler for displaying individual
 * wiki notes. It takes the wiki note name to view from the intent data URL
 * and defaults to a page name defined in R.strings.start_page if no page name
 * is given. The lifecycle events store the current content URL being viewed.
 * It uses Linkify to turn wiki words in the body of the wiki note into
 * clickable links which in turn call back into the WikiNotes activity from
 * the Android operating system. If a URL is passed to the WikiNotes activity
 * for a page that does not yet exist, the WikiNoteEditor activity is
 * automatically started to place the user into edit mode for a new wiki note
 * with the given name.
 */
public class WikiNotes extends Activity {
    /**
     * The view URL which is prepended to a matching wikiword in order to fire
     * the WikiNotes activity again through Linkify
     */

    private static final String KEY_URL = "wikiNotesURL";

    public static final int EDIT_ID = Menu.FIRST;
    public static final int HOME_ID = Menu.FIRST + 1;
    public static final int LIST_ID = Menu.FIRST + 3;
    public static final int DELETE_ID = Menu.FIRST + 4;
    public static final int ABOUT_ID = Menu.FIRST + 5;
    public static final int EXPORT_ID = Menu.FIRST + 6;
    public static final int IMPORT_ID = Menu.FIRST + 7;
    public static final int EMAIL_ID = Menu.FIRST + 8;

    private TextView mNoteView;
    Cursor mCursor;
    private Uri mURI;
    String mNoteName;
    private static final Pattern WIKI_WORD_MATCHER;
    private WikiActivityHelper mHelper;

    static {
	// Compile the regular expression pattern that will be used to
	// match WikiWords in the body of the note
	WIKI_WORD_MATCHER = Pattern
	    .compile("\\b[A-Z]+[a-z0-9]+[A-Z][A-Za-z0-9]+\\b");
    }

    @Override
    public void onCreate(Bundle icicle) {
	super.onCreate(icicle);
	setContentView(R.layout.main);

	mNoteView = (TextView) findViewById(R.id.noteview);

	// get the URL we are being asked to view
	Uri uri = getIntent().getData();

	if ((uri == null) && (icicle != null)) {
	    // perhaps we have the URI in the icicle instead?
	    uri = Uri.parse(icicle.getString(KEY_URL));
	}

	// do we have a correct URI including the note name?
	if ((uri == null) || (uri.getPathSegments().size() < 2)) {
	    // if not, build one using the default StartPage name
	    uri = Uri.withAppendedPath(WikiNote.Notes.ALL_NOTES_URI,
				       getResources()
					   .getString(R.string.start_page));
	}

	// can we find a matching note?
	Cursor cursor = managedQuery(uri, WikiNote.WIKI_NOTES_PROJECTION,
				     null, null, null);

	boolean newNote = false;
	if ((cursor == null) || (cursor.getCount() == 0)) {
	    // no matching wikinote, so create it
	    uri = getContentResolver().insert(uri, null);
	    if (uri == null) {
		Log.e("WikiNotes", "Failed to insert new wikinote into " +
				   getIntent().getData());
		finish();
		return;
	    }
	    // make sure that the new note was created successfully, and
	    // select
	    // it
	    cursor = managedQuery(uri, WikiNote.WIKI_NOTES_PROJECTION, null,
				  null, null);
	    if ((cursor == null) || (cursor.getCount() == 0)) {
		Log.e("WikiNotes", "Failed to open new wikinote: " +
				   getIntent().getData());
		finish();
		return;
	    }
	    newNote = true;
	}

	mURI = uri;
	mCursor = cursor;
	cursor.moveToFirst();
	mHelper = new WikiActivityHelper(this);

	// get the note name
	String noteName = cursor.getString(cursor
	    .getColumnIndexOrThrow(WikiNote.Notes.TITLE));
	mNoteName = noteName;

	// set the title to the name of the page
	setTitle(getResources().getString(R.string.wiki_title, noteName));

	// If a new note was created, jump straight into editing it
	if (newNote) {
	    mHelper.editNote(noteName, null);
	} else if (!getSharedPreferences(Eula.PREFERENCES_EULA,
					 Activity.MODE_PRIVATE)
	    .getBoolean(Eula.PREFERENCE_EULA_ACCEPTED, false)) {
	    Eula.showEula(this);
	}

	// Set the menu shortcut keys to be default keys for the activity as
	// well
	setDefaultKeyMode(DEFAULT_KEYS_SHORTCUT);
    }

    @Override
    protected void onSaveInstanceState(Bundle outState) {
	super.onSaveInstanceState(outState);
	// Put the URL currently being viewed into the icicle
	outState.putString(KEY_URL, mURI.toString());
    }

    @Override
    protected void onResume() {
	super.onResume();
	Cursor c = mCursor;
	if (c.getCount() < 1) {
	    // if the note can't be found, don't try to load it -- bail out
	    // (probably means it got deleted while we were frozen;
	    // thx to joe.bowbeer for the find)
	    finish();
	    return;
	}
	c.requery();
	c.moveToFirst();
	showWikiNote(c
	    .getString(c.getColumnIndexOrThrow(WikiNote.Notes.BODY)));
    }

    /**
     * Show the wiki note in the text edit view with both the default Linkify
     * options and the regular expression for WikiWords matched and turned
     * into live links.
     * 
     * @param body
     *            The plain text to linkify and put into the edit view.
     */
    private void showWikiNote(CharSequence body) {
	TextView noteView = mNoteView;
	noteView.setText(body);

	// Add default links first - phone numbers, URLs, etc.
	Linkify.addLinks(noteView, Linkify.ALL);

	// Now add in the custom linkify match for WikiWords
	Linkify.addLinks(noteView, WIKI_WORD_MATCHER,
			 WikiNote.Notes.ALL_NOTES_URI.toString() + "/");
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
	super.onCreateOptionsMenu(menu);
	menu.add(0, EDIT_ID, 0, R.string.menu_edit).setShortcut('1', 'e')
	    .setIcon(R.drawable.icon_delete);
	menu.add(0, HOME_ID, 0, R.string.menu_start).setShortcut('4', 'h')
	    .setIcon(R.drawable.icon_start);
	menu.add(0, LIST_ID, 0, R.string.menu_recent).setShortcut('3', 'r')
	    .setIcon(R.drawable.icon_recent);
	menu.add(0, DELETE_ID, 0, R.string.menu_delete).setShortcut('2', 'd')
	    .setIcon(R.drawable.icon_delete);
	menu.add(0, ABOUT_ID, 0, R.string.menu_about).setShortcut('5', 'a')
	    .setIcon(android.R.drawable.ic_dialog_info);
	menu.add(0, EXPORT_ID, 0, R.string.menu_export).setShortcut('7', 'x')
	    .setIcon(android.R.drawable.ic_dialog_info);
	menu.add(0, IMPORT_ID, 0, R.string.menu_import).setShortcut('8', 'm')
	    .setIcon(android.R.drawable.ic_dialog_info);	
	menu.add(0, EMAIL_ID, 0, R.string.menu_email).setShortcut('6', 'm')
	    .setIcon(android.R.drawable.ic_dialog_info);
	return true;
    }

    @Override
    public boolean onMenuItemSelected(int featureId, MenuItem item) {
	switch (item.getItemId()) {
	case EDIT_ID:
	    mHelper.editNote(mNoteName, mCursor);
	    return true;
	case HOME_ID:
	    mHelper.goHome();
	    return true;
	case DELETE_ID:
	    mHelper.deleteNote(mCursor);
	    return true;
	case LIST_ID:
	    mHelper.listNotes();
	    return true;
	case WikiNotes.ABOUT_ID:
	    Eula.showEula(this);
	    return true;
	case WikiNotes.EXPORT_ID:
	    mHelper.exportNotes();
	    return true;
	case WikiNotes.IMPORT_ID:
	    mHelper.importNotes();
	    return true;
	case WikiNotes.EMAIL_ID:
	    mHelper.mailNote(mCursor);
	    return true;
	default:
	    return false;
	}
    }

    /**
     * If the note was edited and not canceled, commit the update to the
     * database and then refresh the current view of the linkified note.
     */
    @Override
    protected void onActivityResult(int requestCode, int resultCode,
				    Intent result) {
	super.onActivityResult(requestCode, resultCode, result);
	if ((requestCode == WikiActivityHelper.ACTIVITY_EDIT) &&
	    (resultCode == RESULT_OK)) {
	    // edit was confirmed - store the update
	    Cursor c = mCursor;
	    c.requery();
	    c.moveToFirst();
	    Uri noteUri = ContentUris
		.withAppendedId(WikiNote.Notes.ALL_NOTES_URI, c.getInt(0));
	    ContentValues values = new ContentValues();
	    values.put(WikiNote.Notes.BODY, result
		.getStringExtra(WikiNoteEditor.ACTIVITY_RESULT));
	    values.put(WikiNote.Notes.MODIFIED_DATE, System
		.currentTimeMillis());
	    getContentResolver().update(noteUri, values,
					"_id = " + c.getInt(0), null);
	    showWikiNote(c.getString(c
		.getColumnIndexOrThrow(WikiNote.Notes.BODY)));
	}
    }
}