Android教程之Android自带的语音识别例子初探
主题:Android教程之Android自带的语音识别例子初探
版权申明:http://yarin.javaeye.com/blog/453262
语音识别技术是在Android SDK1.5中才加入的(RecognizerIntent),这里我们简单的分析一下自带的api例子,其实它就是通过一个Intent的Action动作来完成的。主要有以下两种模式:
ACTION_RECOGNIZE_SPEECH:一般语音识别,在这种模式下我们可以捕捉到语音的处理后的文字列。
ACTION_WEB_SEARCH:网络搜索
该例子同样是使用ACTION_RECOGNIZE_SPEECH模式,我们需要实现onActivityResult方法,当语音识别结束之后的回调函数。
好了,废话不多说,看下面的代码,我加入了注释,重要的本来就不多几行。
- package com.example.android.apis.app;
- 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;
- 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);
- setContentView(R.layout.voice_recognition);
- 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");
- }
- }
- public void onClick(View v)
- {
- if (v.getId() == R.id.btn_speak)
- {
- startVoiceRecognitionActivity();
- }
- }
- private void startVoiceRecognitionActivity()
- {
- //通过Intent传递语音识别的模式
- Intent intent = new Intent(RecognizerIntent.ACTION_RECOGNIZE_SPEECH);
- //语言模式和自由形式的语音识别
- intent.putExtra(RecognizerIntent.EXTRA_LANGUAGE_MODEL, RecognizerIntent.LANGUAGE_MODEL_FREE_FORM);
- //提示语音开始
- intent.putExtra(RecognizerIntent.EXTRA_PROMPT, "Speech recognition demo");
- //开始执行我们的Intent、语音识别
- startActivityForResult(intent, VOICE_RECOGNITION_REQUEST_CODE);
- }
- //当语音结束时的回调函数onActivityResult
- @Override
- protected void onActivityResult(int requestCode, int resultCode, Intent data)
- {
- if (requestCode == VOICE_RECOGNITION_REQUEST_CODE && resultCode == RESULT_OK)
- {
- // 取得语音的字符
- 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);
- }
- }
当然这里需要设备的支持,所以模拟器是没有效果的!
实际上在没有设备时会跑出ActivityNotFoundException异常。
这个例子很简单,到此为止,谢谢!