Fix voice service toast generation. (#872)

This service runs in a background thread now, so UI updates need to be
explicitly scheduled in the main thread.

Closes #866

Signed-off-by: Danny Baumann <[email protected]>

mobile/src/main/java/org/openhab/habdroid/core/OpenHABVoiceService.java

@@ -11,6 +11,8 @@
 
 import android.app.IntentService;
 import android.content.Intent;
+import android.os.Handler;
+import android.os.Looper;
 import android.speech.RecognizerIntent;
 import android.support.annotation.Nullable;
 import android.util.Log;
@@ -32,6 +34,7 @@
  */
 public class OpenHABVoiceService extends IntentService {
     private static final String TAG = OpenHABVoiceService.class.getSimpleName();
+    private Handler mHandler = new Handler(Looper.getMainLooper());
 
     public OpenHABVoiceService() {
         super("OpenHABVoiceService");
@@ -56,9 +59,7 @@ protected void onHandleIntent(@Nullable Intent intent) {
         if (connection != null) {
             sendVoiceCommand(connection.getSyncHttpClient(), voiceCommand);
         } else {
-            Toast.makeText(this,
-                    R.string.error_couldnt_determine_openhab_url, Toast.LENGTH_SHORT)
-                    .show();
+            showToast(getString(R.string.error_couldnt_determine_openhab_url));
         }
     }
 
@@ -69,8 +70,7 @@ private String extractVoiceCommand(Intent data) {
             voiceCommand = textMatchList.get(0);
         }
         Log.i(TAG, "Recognized text: " + voiceCommand);
-        final String message = getString(R.string.info_voice_recognized_text, voiceCommand);
-        Toast.makeText(this, message, Toast.LENGTH_LONG).show();
+        showToast(getString(R.string.info_voice_recognized_text, voiceCommand));
         return voiceCommand;
     }
 
@@ -90,4 +90,8 @@ private void sendVoiceCommand(final SyncHttpClient client, final String command)
             Log.e(TAG, "Sending voice command failed", result.error);
         }
     }
+
+    private void showToast(CharSequence text) {
+        mHandler.post(() -> Toast.makeText(this, text, Toast.LENGTH_SHORT).show());
+    }
 }