Java tutorial
/** * SpeechRecognizer.java * Speech Recognition PhoneGap plugin (Android) * * @author Colin Turner * * Copyright (c) 2011, Colin Turner * * MIT Licensed */ package com.urbtek.phonegap; import java.util.ArrayList; import java.util.Iterator; import java.util.List; import org.json.JSONArray; import org.json.JSONObject; import com.phonegap.api.Plugin; import com.phonegap.api.PluginResult; import com.phonegap.api.PluginResult.Status; import android.util.Log; import android.app.Activity; import android.content.Intent; import android.content.pm.PackageManager; import android.speech.RecognizerIntent; /** * Style and such borrowed from the TTS and PhoneListener plugins */ public class SpeechRecognizer extends Plugin { private static final String LOG_TAG = SpeechRecognizer.class.getSimpleName(); public static final String ACTION_INIT = "init"; public static final String ACTION_SPEECH_RECOGNIZE = "startRecognize"; public static final String NOT_PRESENT_MESSAGE = "Speech recognition is not present or enabled"; private String speechRecognizerCallbackId = ""; private boolean recognizerPresent = false; /* (non-Javadoc) * @see com.phonegap.api.Plugin#execute(java.lang.String, org.json.JSONArray, java.lang.String) */ @Override public PluginResult execute(String action, JSONArray args, String callbackId) { // Dispatcher if (ACTION_INIT.equals(action)) { // init if (DoInit()) return new PluginResult(Status.OK); else return new PluginResult(Status.ERROR, NOT_PRESENT_MESSAGE); } else if (ACTION_SPEECH_RECOGNIZE.equals(action)) { // recognize speech if (!recognizerPresent) { return new PluginResult(PluginResult.Status.ERROR, NOT_PRESENT_MESSAGE); } if (!this.speechRecognizerCallbackId.isEmpty()) { return new PluginResult(PluginResult.Status.ERROR, "Speech recognition is in progress."); } this.speechRecognizerCallbackId = callbackId; startSpeechRecognitionActivity(args); PluginResult res = new PluginResult(Status.NO_RESULT); res.setKeepCallback(true); return res; } else { // Invalid action String res = "Unknown action: " + action; return new PluginResult(PluginResult.Status.INVALID_ACTION, res); } } /** * Initialize the speech recognizer by checking if one exists. */ private boolean DoInit() { this.recognizerPresent = IsSpeechRecognizerPresent(); return this.recognizerPresent; } /** * Checks if a recognizer is present on this device */ private boolean IsSpeechRecognizerPresent() { PackageManager pm = ctx.getPackageManager(); List activities = pm.queryIntentActivities(new Intent(RecognizerIntent.ACTION_RECOGNIZE_SPEECH), 0); return !activities.isEmpty(); } /** * Fire an intent to start the speech recognition activity. * * @param args Argument array with the following string args: [req code][number of matches][prompt string] */ private void startSpeechRecognitionActivity(JSONArray args) { int reqCode = 42; //Hitchhiker? int maxMatches = 0; String prompt = ""; try { if (args.length() > 0) { // Request code - passed back to the caller on a successful operation String temp = args.getString(0); reqCode = Integer.parseInt(temp); } if (args.length() > 1) { // Maximum number of matches, 0 means the recognizer decides String temp = args.getString(1); maxMatches = Integer.parseInt(temp); } if (args.length() > 2) { // Optional text prompt prompt = args.getString(2); } } catch (Exception e) { Log.e(LOG_TAG, String.format("startSpeechRecognitionActivity exception: %s", e.toString())); } Intent intent = new Intent(RecognizerIntent.ACTION_RECOGNIZE_SPEECH); intent.putExtra(RecognizerIntent.EXTRA_LANGUAGE_MODEL, RecognizerIntent.LANGUAGE_MODEL_FREE_FORM); if (maxMatches > 0) intent.putExtra(RecognizerIntent.EXTRA_MAX_RESULTS, maxMatches); if (!prompt.isEmpty()) intent.putExtra(RecognizerIntent.EXTRA_PROMPT, prompt); ctx.startActivityForResult(this, intent, reqCode); } /** * Handle the results from the recognition activity. */ @Override public void onActivityResult(int requestCode, int resultCode, Intent data) { if (resultCode == Activity.RESULT_OK) { // Fill the list view with the strings the recognizer thought it could have heard ArrayList<String> matches = data.getStringArrayListExtra(RecognizerIntent.EXTRA_RESULTS); ReturnSpeechResults(requestCode, matches); } else { // Failure - Let the caller know ReturnSpeechFailure(resultCode); } super.onActivityResult(requestCode, resultCode, data); } private void ReturnSpeechResults(int requestCode, ArrayList<String> matches) { boolean firstValue = true; StringBuilder sb = new StringBuilder(); sb.append("{\"speechMatches\": {"); sb.append("\"requestCode\": "); sb.append(Integer.toString(requestCode)); sb.append(", \"speechMatch\": ["); Iterator<String> iterator = matches.iterator(); while (iterator.hasNext()) { String match = iterator.next(); if (firstValue == false) sb.append(", "); firstValue = false; sb.append(JSONObject.quote(match)); } sb.append("]}}"); PluginResult result = new PluginResult(PluginResult.Status.OK, sb.toString()); result.setKeepCallback(false); this.success(result, this.speechRecognizerCallbackId); this.speechRecognizerCallbackId = ""; } private void ReturnSpeechFailure(int resultCode) { PluginResult result = new PluginResult(PluginResult.Status.ERROR, Integer.toString(resultCode)); result.setKeepCallback(false); this.error(result, this.speechRecognizerCallbackId); this.speechRecognizerCallbackId = ""; } }