basic qr scan, get returned qr code

res/layout/activity_registration_qr.xml

@@ -1,13 +1,54 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
-    android:orientation="vertical">
+    android:orientation="vertical"
+    android:gravity="center_horizontal"
+    tools:context=".WelcomeActivity">
 
-    <com.journeyapps.barcodescanner.CompoundBarcodeView
-        android:id="@+id/zxing_barcode_scanner"
+    <androidx.legacy.widget.Space
+        android:layout_weight="1"
         android:layout_width="match_parent"
-        android:layout_height="match_parent"
-        android:layout_alignParentBottom="true" />
+        android:layout_height="0dp"/>
 
-</RelativeLayout>
+    <ImageView
+        android:id="@+id/welcome_icon"
+        android:layout_width="128dp"
+        android:layout_height="128dp"
+        android:src="@drawable/intro1"
+        android:padding="8dp"
+        tools:ignore="contentDescription"/>
+
+    <TextView
+        android:id="@+id/welcome_header"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:gravity="center"
+        android:padding="16dp"
+        android:text="@string/qrscan_title"
+        android:textSize="22sp"
+        android:textStyle="bold"/>
+
+    <RelativeLayout
+        android:layout_width="match_parent"
+        android:layout_height="0dp"
+        android:layout_weight="6"
+        android:layout_marginStart="24dp"
+        android:layout_marginEnd="24dp"
+        android:orientation="vertical">
+
+        <com.journeyapps.barcodescanner.CompoundBarcodeView
+            android:id="@+id/zxing_barcode_scanner"
+            android:layout_width="match_parent"
+            android:layout_height="match_parent"
+            android:layout_alignParentBottom="true" />
+
+    </RelativeLayout>
+
+    <androidx.legacy.widget.Space
+        android:layout_weight="1"
+        android:layout_width="match_parent"
+        android:layout_height="0dp"/>
+
+</LinearLayout>

res/layout/welcome_activity.xml

@@ -26,7 +26,7 @@
         android:layout_height="wrap_content"
         android:gravity="center"
         android:padding="16dp"
-        android:text="@string/app_name"
+        android:text="@string/welcome_desktop"
         android:textSize="22sp"
         android:textStyle="bold"/>
 

src/org/thoughtcrime/securesms/WelcomeActivity.java

@@ -9,6 +9,7 @@ import androidx.annotation.NonNull;
 import androidx.appcompat.app.AlertDialog;
 import android.view.View;
 import android.widget.Button;
+import android.widget.Toast;
 
 import com.b44t.messenger.DcContext;
 import com.b44t.messenger.DcEventCenter;
@@ -152,4 +153,12 @@ public class WelcomeActivity extends BaseActionBarActivity implements DcEventCen
             }
         }
     }
+
+    @Override
+    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
+        super.onActivityResult(requestCode, resultCode, data);
+        if (requestCode==IntentIntegrator.REQUEST_CODE) {
+            Toast.makeText(this, "The scanned QR code cannot be used to set up a new account.", Toast.LENGTH_LONG).show();
+        }
+    }
 }

src/org/thoughtcrime/securesms/qr/RegistrationQrActivity.java

@@ -36,10 +36,6 @@ public class RegistrationQrActivity extends BaseActionBarActivity {
 
         setContentView(R.layout.activity_registration_qr);
 
-        /*assert getSupportActionBar() != null;
-        getSupportActionBar().setTitle(R.string.qrscan_title);
-        getSupportActionBar().setDisplayHomeAsUpEnabled(true);*/
-
         barcodeScannerView = findViewById(R.id.zxing_barcode_scanner);
         barcodeScannerView.setStatusText(getString(R.string.qrscan_hint) + "\n ");