get fcm token on updateGatewayKey btn clicked

.idea/misc.xml

@@ -3,7 +3,7 @@
   <component name="DesignSurface">
     <option name="filePathToZoomLevelMap">
       <map>
-        <entry key="app/src/main/res/layout/activity_main.xml" value="0.1" />
+        <entry key="app/src/main/res/layout/activity_main.xml" value="0.27088470458984376" />
       </map>
     </option>
   </component>

app/build.gradle

@@ -1,5 +1,6 @@
 plugins {
     id 'com.android.application'
+    id 'com.google.gms.google-services'
 }
 
 android {

app/src/main/java/com/vernu/sms/activities/MainActivity.java

@@ -1,5 +1,6 @@
 package com.vernu.sms.activities;
 
+import androidx.annotation.NonNull;
 import androidx.appcompat.app.AppCompatActivity;
 import androidx.core.app.ActivityCompat;
 import androidx.core.content.ContextCompat;
@@ -14,7 +15,10 @@ import android.widget.EditText;
 import android.widget.Switch;
 import android.widget.Toast;
 
+import com.google.android.gms.tasks.OnCompleteListener;
+import com.google.android.gms.tasks.Task;
 import com.google.android.material.snackbar.Snackbar;
+import com.google.firebase.messaging.FirebaseMessaging;
 import com.vernu.sms.R;
 import com.vernu.sms.helpers.SharedPreferenceHelper;
 
@@ -23,7 +27,7 @@ public class MainActivity extends AppCompatActivity {
     private Context mContext;
 
     private Switch gatewaySwitch;
-    private EditText gatewayKeyEditText;
+    private EditText gatewayKeyEditText, fcmTokenEditText;
     private Button updateKeyButton, grantSMSPermissionBtn;
 
     private static final int SEND_SMS_PERMISSION_REQUEST_CODE = 0;
@@ -37,6 +41,7 @@ public class MainActivity extends AppCompatActivity {
         setContentView(R.layout.activity_main);
         gatewaySwitch = findViewById(R.id.gatewaySwitch);
         gatewayKeyEditText = findViewById(R.id.gatewayKeyEditText);
+        fcmTokenEditText = findViewById(R.id.fcmTokenEditText);
         updateKeyButton = findViewById(R.id.updateKeyButton);
         grantSMSPermissionBtn = findViewById(R.id.grantSMSPermissionBtn);
 
@@ -59,6 +64,19 @@ public class MainActivity extends AppCompatActivity {
             public void onClick(View view) {
                 String newKey = gatewayKeyEditText.getText().toString();
                 SharedPreferenceHelper.setSharedPreferenceString(mContext, "GATEWAY_KEY", newKey);
+
+                FirebaseMessaging.getInstance().getToken()
+                        .addOnCompleteListener(new OnCompleteListener<String>() {
+                            @Override
+                            public void onComplete(@NonNull Task<String> task) {
+                                if (!task.isSuccessful()) {
+                                    return;
+                                }
+                                String token = task.getResult();
+                                Toast.makeText(MainActivity.this, token, Toast.LENGTH_SHORT).show();
+                                fcmTokenEditText.setText(token);
+                            }
+                        });
             }
         });
 

app/src/main/res/layout/activity_main.xml

@@ -44,13 +44,24 @@
         app:layout_constraintEnd_toEndOf="parent"
         app:layout_constraintStart_toStartOf="parent" />
 
+    <EditText
+        android:id="@+id/fcmTokenEditText"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:ems="10"
+        android:gravity="start|top"
+        android:inputType="textMultiLine"
+        app:layout_constraintEnd_toEndOf="@+id/gatewayKeyEditText"
+        app:layout_constraintStart_toStartOf="@+id/gatewayKeyEditText"
+        app:layout_constraintTop_toBottomOf="@+id/gatewayKeyEditText" />
+
     <ScrollView
         android:layout_width="409dp"
         android:layout_height="606dp"
         app:layout_constraintBottom_toTopOf="@+id/grantSMSPermissionBtn"
         app:layout_constraintEnd_toEndOf="parent"
         app:layout_constraintStart_toStartOf="parent"
-        app:layout_constraintTop_toBottomOf="@+id/updateKeyButton">
+        app:layout_constraintTop_toBottomOf="@+id/fcmTokenEditText">
 
         <LinearLayout
             android:layout_width="match_parent"
@@ -58,4 +69,5 @@
             android:orientation="vertical"></LinearLayout>
     </ScrollView>
 
+
 </androidx.constraintlayout.widget.ConstraintLayout>