android 轻松实现语音识别

苹果的iphone 有语音识别用的是Google 的技术，做为Google 力推的Android 自然会将其核心技术往Android 系统里面植入，并结合google 的云端技术将其发扬光大。
所以Google Voice Recognition在Android 的实现就变得极其轻松。

语音识别，借助于云端技术可以识别用户的语音输入，包括语音控制等技术，下面我们将利用Google 提供的Api 实现这一功能。
功能点为：通过用户语音将用户输入的语音识别出来，并打印在列表上。
功能界面如下：


用户通过点击speak按钮显示界面：

用户说完话后，将提交到云端搜索：

在云端搜索完成后，返回打印数据：


完整代码如下：
/*
* Copyright (C) 2008 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.R;

import android.app.Activity;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.content.pm.ResolveInfo;
import android.os.Bundle;
import android.speech.RecognizerIntent;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.ListView;

import java.util.ArrayList;
import java.util.List;

/**
* Sample code that invokes the speech recognition intent API.
*/
public
class VoiceRecognition extends Activity implements OnClickListener {
  
    private
static
final
int VOICE_RECOGNITION_REQUEST_CODE =
1234;
  
    private ListView mList;

    /**
     * Called with the activity is first created.
     */
    @Override
    public
void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        // Inflate our UI from its XML layout description.
        setContentView(R.layout.voice_recognition);

        // Get display items for later interaction
        Button speakButton = (Button) findViewById(R.id.btn_speak);
       
        mList = (ListView) findViewById(R.id.list);

        // Check to see if a recognition activity is present
        PackageManager pm = getPackageManager();
        List<ResolveInfo> activities = pm.queryIntentActivities(
                new Intent(RecognizerIntent.ACTION_RECOGNIZE_SPEECH), 0);
        if (activities.size() !=
0) {
            speakButton.setOnClickListener(this);
        } else {
            speakButton.setEnabled(false);
            speakButton.setText("Recognizer not present");
        }
    }

    /**
     * Handle the click on the start recognition button.
     */
public
void onClick(View v) {
        if (v.getId() == R.id.btn_speak) {
            startVoiceRecognitionActivity();
        }
    }

    /**
     * Fire an intent to start the speech recognition activity.
     */
private
void startVoiceRecognitionActivity() {
        Intent intent =
new Intent(RecognizerIntent.ACTION_RECOGNIZE_SPEECH);
        intent.putExtra(RecognizerIntent.EXTRA_LANGUAGE_MODEL,
                RecognizerIntent.LANGUAGE_MODEL_FREE_FORM);
        intent.putExtra(RecognizerIntent.EXTRA_PROMPT, "Speech recognition demo");
        startActivityForResult(intent, VOICE_RECOGNITION_REQUEST_CODE);
    }

    /**
     * Handle the results from the recognition activity.
     */
    @Override
    protected
void onActivityResult(int requestCode, int resultCode, Intent data) {
        if (requestCode == VOICE_RECOGNITION_REQUEST_CODE && resultCode == RESULT_OK) {
            // Fill the list view with the strings the recognizer thought it could have heard
            ArrayList<String> matches = data.getStringArrayListExtra(
                    RecognizerIntent.EXTRA_RESULTS);
            mList.setAdapter(new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1,
                    matches));
        }

        super.onActivityResult(requestCode, resultCode, data);
    }
}