Speech-to-text/app/src/main/java/info/androidhive/speechtotext/MainActivity.java

package info.androidhive.speechtotext;

import java.io.DataOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.Reader;
import java.io.UnsupportedEncodingException;
import java.net.HttpURLConnection;
import java.net.URL;
import java.nio.charset.StandardCharsets;
import java.util.ArrayList;
import java.util.Locale;

import android.app.Activity;
import android.content.ActivityNotFoundException;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.os.AsyncTask;
import android.os.Bundle;
import android.preference.PreferenceManager;
import android.speech.RecognizerIntent;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.ImageButton;
import android.widget.TextView;
import android.widget.Toast;

public class MainActivity extends Activity {

	private TextView txtSpeechInput;
	private ImageButton btnSpeak;
	private final int REQ_CODE_SPEECH_INPUT = 100;
	private final int REQ_PREF				= 200;
	public static final String TAG = MainActivity.class.getSimpleName();
	public static final int MAX_ANSWER_LEN = 500;
	public static String Url;

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);

		txtSpeechInput = (TextView) findViewById(R.id.txtSpeechInput);
		btnSpeak = (ImageButton) findViewById(R.id.btnSpeak);

		// hide the action bar
		//getActionBar().hide();

		btnSpeak.setOnClickListener(new View.OnClickListener() {

			@Override
			public void onClick(View v) {
				promptSpeechInput();
			}
		});
		new SilentTalkToMeTask().execute("goodbye");
		SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(this);
		Url = preferences.getString(SettingsActivity.KEY_PREF_SERVER_URL, "");
		Log.d(TAG, "Server url is " + Url);
	}

	/**
	 * Showing google speech input dialog
	 * */
	private void promptSpeechInput() {
		Intent intent = new Intent(RecognizerIntent.ACTION_RECOGNIZE_SPEECH);
		intent.putExtra(RecognizerIntent.EXTRA_LANGUAGE_MODEL,
				RecognizerIntent.LANGUAGE_MODEL_FREE_FORM);
		intent.putExtra(RecognizerIntent.EXTRA_LANGUAGE, Locale.getDefault());
		intent.putExtra(RecognizerIntent.EXTRA_PROMPT,
				getString(R.string.speech_prompt));
		try {
			startActivityForResult(intent, REQ_CODE_SPEECH_INPUT);
		} catch (ActivityNotFoundException a) {
			Toast.makeText(getApplicationContext(),
					getString(R.string.speech_not_supported),
					Toast.LENGTH_SHORT).show();
		}
	}

	@Override
	protected void onActivityResult(int requestCode, int resultCode, Intent data) {
		super.onActivityResult(requestCode, resultCode, data);

		switch (requestCode) {
		case REQ_CODE_SPEECH_INPUT: {
			if (resultCode == RESULT_OK && null != data) {

				ArrayList<String> result = data
						.getStringArrayListExtra(RecognizerIntent.EXTRA_RESULTS);
				txtSpeechInput.setText(result.get(0));

				ConnectivityManager connMgr = (ConnectivityManager)
						getSystemService(Context.CONNECTIVITY_SERVICE);
				NetworkInfo networkInfo = connMgr.getActiveNetworkInfo();
				if (networkInfo != null && networkInfo.isConnected()) {
					new TalkToMeTask().execute(result.get(0));
				} else {
					txtSpeechInput.setText("No network connection available.");
				}
			}
			break;
		}
			case REQ_PREF:{
				SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(this);
				Url = preferences.getString(SettingsActivity.KEY_PREF_SERVER_URL, "");
			}
			break;

		}
	}

	@Override
	public boolean onCreateOptionsMenu(Menu menu) {
		// Inflate the menu; this adds items to the action bar if it is present.
		getMenuInflater().inflate(R.menu.main, menu);
		return true;
	}

	@Override
	public boolean onOptionsItemSelected(MenuItem item) {
		switch (item.getItemId()) {
			case R.id.action_settings:
				startActivityForResult(new Intent(getBaseContext(), SettingsActivity.class), REQ_PREF);
				return true;
		}
		return super.onOptionsItemSelected(item);
	}

	private class TalkToMeTask extends AsyncTask<String,Void, String>{

		@Override
		protected String doInBackground(String... question) {
			try {
				return talkToServer(question[0]);
			} catch (IOException e){
				Log.d(TAG, e.toString());
				return "Cannot connect to server";
			}
		}

		@Override
		protected void onPostExecute(String s) {
			txtSpeechInput.setText(s);
		}
	}

	private class SilentTalkToMeTask extends AsyncTask<String,Void, String>{

		@Override
		protected String doInBackground(String... question) {
			try {
				return talkToServer(question[0]);
			} catch (IOException e){
				Log.d(TAG, e.toString());
				return "Cannot connect to server";
			}
		}

		@Override
		protected void onPostExecute(String s) {
		}
	}

	private String talkToServer(String question) throws IOException {
		InputStream is = null;
		try {
			URL url = new URL(Url);
			String urlParameters  = "msg="+question;
			byte[] postData       = urlParameters.getBytes( StandardCharsets.UTF_8 );
			int    postDataLength = postData.length;
			HttpURLConnection conn = (HttpURLConnection) url.openConnection();
			conn.setDoOutput( true );
			conn.setInstanceFollowRedirects( false );
			conn.setRequestMethod("POST");
			conn.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
			conn.setRequestProperty("charset", "utf-8");
			conn.setRequestProperty( "Content-Length", Integer.toString( postData.length ));
			conn.setUseCaches(false);
			DataOutputStream wr = new DataOutputStream( conn.getOutputStream());
			wr.write(postData);

			conn.connect();
			int response = conn.getResponseCode();
			Log.d(TAG, "The response is: " + response);
			is = conn.getInputStream();


			String contentAsString = readIt(is, MAX_ANSWER_LEN);
			return contentAsString;

		} finally {
			if (is != null){
				is.close();
			}
		}
	}
	// Reads an InputStream and converts it to a String.
	public String readIt(InputStream stream, int len) throws IOException, UnsupportedEncodingException {
		Reader reader = null;
		reader = new InputStreamReader(stream, "UTF-8");
		char[] buffer = new char[len];
		reader.read(buffer);
		return new String(buffer);
	}


}