如何在 Xamarin.Android C# 中将文本更改为语音语言

Question

I wanted to make a text to speech application for a project and I used this as a reference: https://github.com/xamarin/monodroid-samples/tree/main/PlatformFeatures/TextToSpeech

However, whenever i open the app it always opens up the google tts service and I cannot change the language, and the spinner does not show any languages only "Default" is there a way to make this program not open up google tts service each time and making the language options available on the spinner? thanks so much!

using Android.App;
using Android.Content;
using Android.OS;
using Android.Runtime;
using Android.Views;
using Android.Widget;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Android.Support.V7.App;
using Android.Speech.Tts;
using Java.Util;
using Android.Graphics;

namespace DND_Connect
{
    [Activity(Label = "Deaf")]
    public class DeafPage : Activity, TextToSpeech.IOnInitListener
    {
        TextToSpeech textToSpeech;
        Context context;
        private readonly int MyCheckCode = 101, NeedLang = 103;
        Java.Util.Locale lang;

        protected override void OnCreate(Bundle bundle)
        {
            base.OnCreate(bundle);
            SetContentView(Resource.Layout.deaf);

            var btnSayIt = FindViewById<Button>(Resource.Id.buttonSpeak);
            var editWhatToSay = FindViewById<EditText>(Resource.Id.edtSpch);
            var spinLanguages = FindViewById<Spinner>(Resource.Id.spnLng);
            var txtSpeedVal = FindViewById<TextView>(Resource.Id.txtSpeed);
            var txtPitchVal = FindViewById<TextView>(Resource.Id.txtPitch);
            var seekSpeed = FindViewById<SeekBar>(Resource.Id.skSpeed);
            var seekPitch = FindViewById<SeekBar>(Resource.Id.skPitch);

            var txtView = FindViewById<TextView>(Resource.Id.deaftitle);
            var txtView1 = FindViewById<TextView>(Resource.Id.deafdesc);
            Typeface tf = Typeface.CreateFromAsset(Assets, "Roboto-Condensed.ttf");
            txtView.SetTypeface(tf, Android.Graphics.TypefaceStyle.Normal);
            txtView1.SetTypeface(tf, Android.Graphics.TypefaceStyle.Normal);

            seekSpeed.Progress = seekPitch.Progress = 127;
            txtSpeedVal.Text = txtPitchVal.Text = "0.5";

            context = btnSayIt.Context;

            textToSpeech = new TextToSpeech(this, this, "com.google.android.tts");

            var langAvailable = new List<string> { "Default" };

            var localesAvailable = Java.Util.Locale.GetAvailableLocales().ToList();
            foreach (var locale in localesAvailable)
            {
                LanguageAvailableResult res = textToSpeech.IsLanguageAvailable(locale);
                switch (res)
                {
                    case LanguageAvailableResult.Available:
                        langAvailable.Add(locale.DisplayLanguage);
                        break;
                    case LanguageAvailableResult.CountryAvailable:
                        langAvailable.Add(locale.DisplayLanguage);
                        break;
                    case LanguageAvailableResult.CountryVarAvailable:
                        langAvailable.Add(locale.DisplayLanguage);
                        break;
                }

            }
            langAvailable = langAvailable.OrderBy(t => t).Distinct().ToList();

            var adapter = new ArrayAdapter<string>(this, Android.Resource.Layout.SimpleSpinnerDropDownItem, langAvailable);
            spinLanguages.Adapter = adapter;

            lang = Java.Util.Locale.Default;
            textToSpeech.SetLanguage(lang);

            textToSpeech.SetPitch(.5f);
            textToSpeech.SetSpeechRate(.5f);

            btnSayIt.Click += delegate
            {
                if (!string.IsNullOrEmpty(editWhatToSay.Text))
                    textToSpeech.Speak(editWhatToSay.Text, QueueMode.Flush, null);
            };

            seekPitch.StopTrackingTouch += (object sender, SeekBar.StopTrackingTouchEventArgs e) =>
            {
                var seek = sender as SeekBar;
                var progress = seek.Progress / 255f;
                textToSpeech.SetPitch(progress);
                txtPitchVal.Text = progress.ToString("F2");
            };
            seekSpeed.StopTrackingTouch += (object sender, SeekBar.StopTrackingTouchEventArgs e) =>
            {
                var seek = sender as SeekBar;
                var progress = seek.Progress / 255f;
                textToSpeech.SetSpeechRate(progress);
                txtSpeedVal.Text = progress.ToString("F2");
            };

            spinLanguages.ItemSelected += (object sender, AdapterView.ItemSelectedEventArgs e) =>
            {
                lang = Java.Util.Locale.GetAvailableLocales().FirstOrDefault(t => t.DisplayLanguage == langAvailable[(int)e.Id]);
                var checkTTSIntent = new Intent();
                checkTTSIntent.SetAction(TextToSpeech.Engine.ActionCheckTtsData);
                StartActivityForResult(checkTTSIntent, NeedLang);
            };
        }
        void TextToSpeech.IOnInitListener.OnInit(OperationResult status)
        {
            if (status == OperationResult.Error)
                textToSpeech.SetLanguage(Java.Util.Locale.Default);
            if (status == OperationResult.Success)
                textToSpeech.SetLanguage(lang);
        }
        protected override void OnActivityResult(int req, Result res, Intent data)
        {
            if (req == NeedLang)
            {
                var installTTS = new Intent();
                installTTS.SetAction(TextToSpeech.Engine.ActionInstallTtsData);
                StartActivity(installTTS);
            }
        }
    }
}

Answer 1

[assembly: Xamarin.Forms.Dependency(typeof(TextToSpeechImplementation))] namespace ShopFloor_Automation.Droid.Implementations { public class TextToSpeechImplementation : Java.Lang.Object, ITextToSpeech, TextToSpeech.IOnInitListener { TextToSpeech speaker; string toSpeak;

    public TextToSpeechImplementation() { }
    public void OnInit([GeneratedEnum] OperationResult status)
    {
        if (status.Equals(OperationResult.Success))
        {
            var p = new Dictionary<string, string>();
            speaker.Speak(toSpeak, QueueMode.Flush, p);
        }
    }

    public void Speak(string text)
    {
        var ctx = Forms.Context; // useful for many Android SDK features
        toSpeak = text;
        if (speaker == null)
        {
            speaker = new TextToSpeech(ctx, this);
        }
        else
        {
            var p = new Dictionary<string, string>();
            speaker.Speak(toSpeak, QueueMode.Flush, p);
        }
    }
}

}