Add error toasts to multiforward sheet.

app/src/main/java/org/thoughtcrime/securesms/contacts/paged/ContactSearchError.kt

@@ -0,0 +1,7 @@
+package org.thoughtcrime.securesms.contacts.paged
+
+enum class ContactSearchError {
+  CONTACT_NOT_SELECTABLE,
+  RECOMMENDED_LIMIT_REACHED,
+  HARD_LIMIT_REACHED
+}

app/src/main/java/org/thoughtcrime/securesms/contacts/paged/ContactSearchMediator.kt

@@ -7,6 +7,8 @@ import androidx.lifecycle.LiveData
 import androidx.lifecycle.ViewModelProvider
 import androidx.recyclerview.widget.RecyclerView
 import com.google.android.material.dialog.MaterialAlertDialogBuilder
+import io.reactivex.rxjava3.android.schedulers.AndroidSchedulers
+import io.reactivex.rxjava3.core.Observable
 import org.thoughtcrime.securesms.R
 import org.thoughtcrime.securesms.groups.SelectionLimits
 import org.thoughtcrime.securesms.keyvalue.SignalStore
@@ -82,6 +84,10 @@ class ContactSearchMediator(
     return viewModel.selectionState
   }
 
+  fun getErrorEvents(): Observable<ContactSearchError> {
+    return viewModel.errorEventsStream.observeOn(AndroidSchedulers.mainThread())
+  }
+
   fun addToVisibleGroupStories(groupStories: Set<ContactSearchKey.RecipientSearchKey.Story>) {
     viewModel.addToVisibleGroupStories(groupStories)
   }

app/src/main/java/org/thoughtcrime/securesms/contacts/paged/ContactSearchViewModel.kt

@@ -5,8 +5,10 @@ import androidx.lifecycle.MutableLiveData
 import androidx.lifecycle.Transformations
 import androidx.lifecycle.ViewModel
 import androidx.lifecycle.ViewModelProvider
+import io.reactivex.rxjava3.core.Observable
 import io.reactivex.rxjava3.disposables.CompositeDisposable
 import io.reactivex.rxjava3.kotlin.plusAssign
+import io.reactivex.rxjava3.subjects.PublishSubject
 import org.signal.paging.LivePagedData
 import org.signal.paging.PagedData
 import org.signal.paging.PagingConfig
@@ -38,11 +40,13 @@ class ContactSearchViewModel(
   private val pagedData = MutableLiveData<LivePagedData<ContactSearchKey, ContactSearchData>>()
   private val configurationStore = Store(ContactSearchState())
   private val selectionStore = Store<Set<ContactSearchKey>>(emptySet())
+  private val errorEvents = PublishSubject.create<ContactSearchError>()
 
   val controller: LiveData<PagingController<ContactSearchKey>> = Transformations.map(pagedData) { it.controller }
   val data: LiveData<List<ContactSearchData>> = Transformations.switchMap(pagedData) { it.data }
   val configurationState: LiveData<ContactSearchState> = configurationStore.stateLiveData
   val selectionState: LiveData<Set<ContactSearchKey>> = selectionStore.stateLiveData
+  val errorEventsStream: Observable<ContactSearchError> = errorEvents
 
   override fun onCleared() {
     disposables.clear()
@@ -64,7 +68,7 @@ class ContactSearchViewModel(
   fun setKeysSelected(contactSearchKeys: Set<ContactSearchKey>) {
     disposables += contactSearchRepository.filterOutUnselectableContactSearchKeys(contactSearchKeys).subscribe { results ->
       if (results.any { !it.isSelectable }) {
-        // TODO [alex] -- Pop an error.
+        errorEvents.onNext(ContactSearchError.CONTACT_NOT_SELECTABLE)
         return@subscribe
       }
 
@@ -72,9 +76,9 @@ class ContactSearchViewModel(
       val newSelectionSize = newSelectionEntries.size + getSelectedContacts().size
 
       if (selectionLimits.hasRecommendedLimit() && getSelectedContacts().size < selectionLimits.recommendedLimit && newSelectionSize >= selectionLimits.recommendedLimit) {
-        // Pop a warning
+        errorEvents.onNext(ContactSearchError.RECOMMENDED_LIMIT_REACHED)
       } else if (selectionLimits.hasHardLimit() && newSelectionSize > selectionLimits.hardLimit) {
-        // Pop an error
+        errorEvents.onNext(ContactSearchError.HARD_LIMIT_REACHED)
         return@subscribe
       }
 

app/src/main/java/org/thoughtcrime/securesms/conversation/mutiselect/forward/MultiselectForwardFragment.kt

@@ -34,6 +34,7 @@ import org.thoughtcrime.securesms.components.ContactFilterView
 import org.thoughtcrime.securesms.components.TooltipPopup
 import org.thoughtcrime.securesms.components.WrapperDialogFragment
 import org.thoughtcrime.securesms.contacts.paged.ContactSearchConfiguration
+import org.thoughtcrime.securesms.contacts.paged.ContactSearchError
 import org.thoughtcrime.securesms.contacts.paged.ContactSearchKey
 import org.thoughtcrime.securesms.contacts.paged.ContactSearchMediator
 import org.thoughtcrime.securesms.contacts.paged.ContactSearchState
@@ -197,6 +198,19 @@ class MultiselectForwardFragment :
       }
     }
 
+    disposables += contactSearchMediator
+      .getErrorEvents()
+      .subscribe {
+        @Suppress("WHEN_ENUM_CAN_BE_NULL_IN_JAVA")
+        val message: Int = when (it) {
+          ContactSearchError.CONTACT_NOT_SELECTABLE -> R.string.MultiselectForwardFragment__only_admins_can_send_messages_to_this_group
+          ContactSearchError.RECOMMENDED_LIMIT_REACHED -> R.string.ContactSelectionListFragment_recommended_member_limit_reached
+          ContactSearchError.HARD_LIMIT_REACHED -> R.string.MultiselectForwardFragment__limit_reached
+        }
+
+        Toast.makeText(requireContext(), message, Toast.LENGTH_SHORT).show()
+      }
+
     viewModel.state.observe(viewLifecycleOwner) {
       when (it.stage) {
         MultiselectForwardState.Stage.Selection -> {}

app/src/main/res/values/strings.xml

@@ -4190,6 +4190,8 @@
         <item quantity="one">Couldn\'t forward message because it\'s no longer available.</item>
         <item quantity="other">Couldn\'t forward messages because they\'re no longer available.</item>
     </plurals>
+    <!-- Error message shown when attempting to select a group to forward/share but it's announcement only and you are not an admin -->
+    <string name="MultiselectForwardFragment__only_admins_can_send_messages_to_this_group">Only admins can send messages to this group.</string>
     <string name="MultiselectForwardFragment__limit_reached">Limit reached</string>
 
     <!-- Media V2 -->