Add a hint that both parties need to add each other's links.

briar-android/src/main/java/org/briarproject/briar/android/contact/add/remote/LinkExchangeFragment.java

@@ -122,6 +122,9 @@ public class LinkExchangeFragment extends BaseFragment {
 						.startChooser());
 		shareButton.setEnabled(true);
 
+		TextView infoText = v.findViewById(R.id.info_text);
+		infoText.setText(R.string.info_both_must_enter_links);
+
 		Button continueButton = v.findViewById(R.id.addButton);
 		continueButton.setOnClickListener(view -> onContinueButtonClicked());
 		continueButton.setEnabled(true);

briar-android/src/main/res/layout/fragment_link_exchange.xml

@@ -30,8 +30,7 @@
 				app:layout_constraintBottom_toTopOf="@+id/stepOneText"
 				app:layout_constraintEnd_toStartOf="@+id/guideline"
 				app:layout_constraintStart_toStartOf="parent"
-				app:layout_constraintTop_toTopOf="parent"
-				app:layout_constraintVertical_bias="0.0" />
+				app:layout_constraintTop_toTopOf="parent" />
 
 			<TextView
 				android:id="@+id/stepOneText"
@@ -64,7 +63,6 @@
 				app:layout_constraintEnd_toEndOf="parent"
 				app:layout_constraintStart_toStartOf="@+id/guideline"
 				app:layout_constraintTop_toTopOf="@+id/stepOne"
-				app:layout_constraintVertical_bias="0.0"
 				app:layout_constraintVertical_chainStyle="packed" />
 
 			<TextView
@@ -162,7 +160,6 @@
 				app:drawableStartCompat="@drawable/social_share_blue"
 				app:layout_constraintBottom_toBottomOf="@id/copyButton"
 				app:layout_constraintEnd_toEndOf="parent"
-				app:layout_constraintHorizontal_bias="1.0"
 				app:layout_constraintStart_toEndOf="@id/copyButton"
 				app:layout_constraintTop_toTopOf="@id/copyButton" />
 
@@ -226,8 +223,18 @@
 				app:layout_constraintHorizontal_bias="1.0"
 				app:layout_constraintStart_toStartOf="parent"
 				app:layout_constraintTop_toBottomOf="@+id/linkInputLayout"
+				app:layout_constraintBottom_toTopOf="@+id/infoView"
 				app:layout_constraintVertical_bias="0.0" />
 
+			<org.briarproject.briar.android.view.InfoView
+				android:id="@+id/infoView"
+				android:layout_width="match_parent"
+				android:layout_height="wrap_content"
+				android:layout_marginTop="16dp"
+				app:layout_constraintEnd_toEndOf="parent"
+				app:layout_constraintStart_toStartOf="parent"
+				app:layout_constraintTop_toBottomOf="@+id/pasteButton" />
+
 		</androidx.constraintlayout.widget.ConstraintLayout>
 	</ScrollView>
 

briar-android/src/main/res/values/strings.xml

@@ -318,6 +318,7 @@
 	<string name="different_person_button">Different Person</string>
 	<string name="duplicate_link_dialog_text_3">%1$s and %2$s sent you the same link.\n\nOne of them may be trying to discover who your contacts are.\n\nDon\'t tell them you received the same link from someone else.</string>
 	<string name="pending_contact_updated_toast">Pending contact updated</string>
+	<string name="info_both_must_enter_links">You must both add each other\'s links</string>
 
 	<!-- Peer trust levels -->