无法调用Android Studio中的TextToSpeech /无法正常工作

Question

The below simple code which makes an intent and calls another view group, is all from the basic first app tutorial.

https://developer.android.com/training/basics/firstapp/starting-activity.html

I used this question as a guide to getting TTS, and the app runs the toast and the view but skips the text to speech: Text to speech(TTS)-Android

I then tried to add a TTS call/ class. I am quite new to Android, so was wondering if someone could explain to me, or point me in the right direction about how to use the classes and build around them to help my general understanding, but overall a solution to this problem would be great, many thanks!

package com.example.ollie.myapplication3;

    import android.content.Context;
    import android.content.Intent;
    import android.net.Uri;
    import android.os.Build;
    import android.speech.tts.TextToSpeech;
    import android.support.annotation.RequiresApi;
    import android.support.v7.app.AppCompatActivity;
    import android.os.Bundle;
    import android.view.View;
    import android.widget.EditText;
    import android.widget.Toast;

    import com.google.android.gms.appindexing.Action;
    import com.google.android.gms.appindexing.AppIndex;
    import com.google.android.gms.appindexing.Thing;
    import com.google.android.gms.common.api.GoogleApiClient;

    import java.util.Locale;

    public class MainActivity extends AppCompatActivity implements TextToSpeech.OnInitListener {

        public static final String EXTRA_MESSAGE = "com.example.myapplication.MESSAGE";
        /**
         * ATTENTION: This was auto-generated to implement the App Indexing API.
         * See https://g.co/AppIndexing/AndroidStudio for more information.
         */
        private GoogleApiClient client;

        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);
            // ATTENTION: This was auto-generated to implement the App Indexing API.
            // See https://g.co/AppIndexing/AndroidStudio for more information.
            client = new GoogleApiClient.Builder(this).addApi(AppIndex.API).build();
        }

        /**
         * Called when user clicks send button
         */
        public void sendMessage(View view) {

            TextToSpeech tts = new TextToSpeech(this, this);
            tts.setLanguage(Locale.US);
            tts.speak("Text to say aloud", TextToSpeech.QUEUE_ADD, null, null);

            Context context = getApplicationContext();
            CharSequence text = "Hello toast!";
            int duration = Toast.LENGTH_LONG;

            Toast toast = Toast.makeText(context, text, duration);
            toast.show();

            Intent intent = new Intent(this, DisplayMessageActivity.class);
            EditText editText = (EditText) findViewById(R.id.edit_message);
            String message = editText.getText().toString();
            intent.putExtra(EXTRA_MESSAGE, message);
            startActivity(intent);
        }

        @Override
        public void onInit(int status) {
            TextToSpeech tts = new TextToSpeech(this, this);
            tts.setLanguage(Locale.US);
            tts.speak("Text to say aloud", TextToSpeech.QUEUE_ADD, null, null);
        }
    }

Answer 1

Try to make your 'tts' variable a local one (in the activity) so you make sure you are using the same instance you have instantiated instead of creating a new one everytime you press the button.

Like this:

public class MainActivity extends AppCompatActivity {

private TextToSpeech tts;


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

    tts = new TextToSpeech(getApplicationContext(), new TextToSpeech.OnInitListener() {
        @Override
        public void onInit(int status) {
            if(status != TextToSpeech.ERROR) {
                tts.setLanguage(Locale.US);
            }
        }
    });

}


public void sendMessage(View view) {
    tts.speak("Text to say aloud", TextToSpeech.QUEUE_ADD, null, null);

    ...
}

}