Improve various aspects of mentions.

app/src/main/java/org/thoughtcrime/securesms/conversation/ConversationActivity.java

@@ -1902,7 +1902,12 @@ public class ConversationActivity extends PassphraseRequiredActivity
   private void initializeMentionsViewModel() {
     MentionsPickerViewModel mentionsViewModel = ViewModelProviders.of(this, new MentionsPickerViewModel.Factory()).get(MentionsPickerViewModel.class);
 
-    recipient.observe(this, mentionsViewModel::onRecipientChange);
+    recipient.observe(this, r -> {
+      if (r.isPushV2Group() && !mentionsSuggestions.resolved()) {
+        mentionsSuggestions.get();
+      }
+      mentionsViewModel.onRecipientChange(r);
+    });
 
     composeText.setMentionQueryChangedListener(query -> {
       if (getRecipient().isPushV2Group()) {

app/src/main/java/org/thoughtcrime/securesms/conversation/ui/mentions/MentionsPickerViewModel.java

@@ -15,6 +15,8 @@ import org.thoughtcrime.securesms.dependencies.ApplicationDependencies;
 import org.thoughtcrime.securesms.groups.GroupId;
 import org.thoughtcrime.securesms.groups.LiveGroup;
 import org.thoughtcrime.securesms.groups.ui.GroupMemberEntry.FullMember;
+import org.thoughtcrime.securesms.megaphone.MegaphoneRepository;
+import org.thoughtcrime.securesms.megaphone.Megaphones;
 import org.thoughtcrime.securesms.recipients.Recipient;
 import org.thoughtcrime.securesms.util.MappingModel;
 import org.thoughtcrime.securesms.util.SingleLiveEvent;
@@ -30,8 +32,11 @@ public class MentionsPickerViewModel extends ViewModel {
   private final MutableLiveData<LiveGroup>      group;
   private final MutableLiveData<Query>          liveQuery;
   private final MutableLiveData<Boolean>        isShowing;
+  private final MegaphoneRepository             megaphoneRepository;
+
+  MentionsPickerViewModel(@NonNull MentionsPickerRepository mentionsPickerRepository, @NonNull MegaphoneRepository megaphoneRepository) {
+    this.megaphoneRepository = megaphoneRepository;
 
-  MentionsPickerViewModel(@NonNull MentionsPickerRepository mentionsPickerRepository) {
     group             = new MutableLiveData<>();
     liveQuery         = new MutableLiveData<>(Query.NONE);
     selectedRecipient = new SingleLiveEvent<>();
@@ -50,6 +55,7 @@ public class MentionsPickerViewModel extends ViewModel {
 
   void onSelectionChange(@NonNull Recipient recipient) {
     selectedRecipient.setValue(recipient);
+    megaphoneRepository.markFinished(Megaphones.Event.MENTIONS);
   }
 
   void setIsShowing(boolean isShowing) {
@@ -116,7 +122,8 @@ public class MentionsPickerViewModel extends ViewModel {
     @Override
     public @NonNull <T extends ViewModel> T create(@NonNull Class<T> modelClass) {
       //noinspection ConstantConditions
-      return modelClass.cast(new MentionsPickerViewModel(new MentionsPickerRepository(ApplicationDependencies.getApplication())));
+      return modelClass.cast(new MentionsPickerViewModel(new MentionsPickerRepository(ApplicationDependencies.getApplication()),
+                                                         ApplicationDependencies.getMegaphoneRepository()));
     }
   }
 }

app/src/main/java/org/thoughtcrime/securesms/megaphone/MegaphoneRepository.java

@@ -101,6 +101,11 @@ public class MegaphoneRepository {
   @AnyThread
   public void markFinished(@NonNull Event event) {
     executor.execute(() -> {
+      MegaphoneRecord record = databaseCache.get(event);
+      if (record != null && record.isFinished()) {
+        return;
+      }
+
       database.markFinished(event);
       resetDatabaseCache();
     });

app/src/main/java/org/thoughtcrime/securesms/megaphone/Megaphones.java

@@ -211,7 +211,7 @@ public final class Megaphones {
   }
 
   private static boolean shouldShowMentionsMegaphone() {
-    return FeatureFlags.mentions() && FeatureFlags.groupsV2();
+    return FeatureFlags.mentions();
   }
 
   private static boolean shouldShowLinkPreviewsMegaphone(@NonNull Context context) {

app/src/main/java/org/thoughtcrime/securesms/util/FeatureFlags.java

@@ -233,7 +233,7 @@ public final class FeatureFlags {
 
   /** Whether or not we allow mentions send support in groups. */
   public static boolean mentions() {
-    return getBoolean(MENTIONS, false);
+    return groupsV2() && getBoolean(MENTIONS, false);
   }
 
   /** Whether or not to use the UUID in verification codes. */