Properly handle media validation errors.

app/src/main/java/org/thoughtcrime/securesms/mediasend/v2/MediaSelectionActivity.kt

@@ -99,6 +99,14 @@ class MediaSelectionActivity :
     overridePendingTransition(R.anim.stationary, R.anim.camera_slide_to_bottom)
   }
 
+  override fun onNoMediaSelected() {
+    Log.w(TAG, "No media selected. Exiting.")
+
+    setResult(RESULT_CANCELED)
+    finish()
+    overridePendingTransition(R.anim.stationary, R.anim.camera_slide_to_bottom)
+  }
+
   override fun onPopFromReview() {
     if (isCameraFirst()) {
       viewModel.removeCameraFirstCapture()

app/src/main/java/org/thoughtcrime/securesms/mediasend/v2/MediaSelectionViewModel.kt

@@ -20,6 +20,7 @@ import org.thoughtcrime.securesms.mms.SentMediaQuality
 import org.thoughtcrime.securesms.recipients.Recipient
 import org.thoughtcrime.securesms.recipients.RecipientId
 import org.thoughtcrime.securesms.scribbles.ImageEditorFragment
+import org.thoughtcrime.securesms.util.SingleLiveEvent
 import org.thoughtcrime.securesms.util.Util
 import org.thoughtcrime.securesms.util.livedata.Store
 import java.util.Collections
@@ -48,8 +49,8 @@ class MediaSelectionViewModel(
   val state: LiveData<MediaSelectionState> = store.stateLiveData
 
   private val internalHudCommands = PublishSubject.create<HudCommand>()
-  private val internalFilterErrors = PublishSubject.create<MediaValidator.FilterError>()
 
+  val mediaErrors: SingleLiveEvent<MediaValidator.FilterError> = SingleLiveEvent()
   val hudCommands: Observable<HudCommand> = internalHudCommands
 
   private val disposables = CompositeDisposable()
@@ -125,7 +126,7 @@ class MediaSelectionViewModel(
           }
 
           if (filterResult.filterError != null) {
-            internalFilterErrors.onNext(filterResult.filterError)
+            mediaErrors.postValue(filterResult.filterError)
           }
         }
     )
@@ -197,7 +198,7 @@ class MediaSelectionViewModel(
     }
 
     if (newMediaList.isEmpty()) {
-      internalFilterErrors.onNext(MediaValidator.FilterError.NO_ITEMS)
+      mediaErrors.postValue(MediaValidator.FilterError.NO_ITEMS)
     }
 
     repository.deleteBlobs(listOf(media))

app/src/main/java/org/thoughtcrime/securesms/mediasend/v2/gallery/MediaSelectionGalleryFragment.kt

@@ -2,15 +2,18 @@ package org.thoughtcrime.securesms.mediasend.v2.gallery
 
 import android.os.Bundle
 import android.view.View
+import android.widget.Toast
 import androidx.activity.OnBackPressedCallback
 import androidx.fragment.app.Fragment
 import androidx.fragment.app.viewModels
 import androidx.recyclerview.widget.ItemTouchHelper
+import app.cash.exhaustive.Exhaustive
 import org.thoughtcrime.securesms.R
 import org.thoughtcrime.securesms.mediasend.Media
 import org.thoughtcrime.securesms.mediasend.v2.MediaSelectionNavigator
 import org.thoughtcrime.securesms.mediasend.v2.MediaSelectionNavigator.Companion.requestPermissionsForCamera
 import org.thoughtcrime.securesms.mediasend.v2.MediaSelectionViewModel
+import org.thoughtcrime.securesms.mediasend.v2.MediaValidator
 import org.thoughtcrime.securesms.mediasend.v2.review.MediaSelectionItemTouchHelper
 import org.thoughtcrime.securesms.permissions.Permissions
 
@@ -47,6 +50,16 @@ class MediaSelectionGalleryFragment : Fragment(R.layout.fragment_container), Med
         }
       )
     }
+
+    sharedViewModel.mediaErrors.observe(viewLifecycleOwner) { error: MediaValidator.FilterError ->
+      @Exhaustive
+      when (error) {
+        MediaValidator.FilterError.ITEM_TOO_LARGE -> Toast.makeText(requireContext(), R.string.MediaReviewFragment__one_or_more_items_were_too_large, Toast.LENGTH_SHORT).show()
+        MediaValidator.FilterError.ITEM_INVALID_TYPE -> Toast.makeText(requireContext(), R.string.MediaReviewFragment__one_or_more_items_were_invalid, Toast.LENGTH_SHORT).show()
+        MediaValidator.FilterError.TOO_MANY_ITEMS -> Toast.makeText(requireContext(), R.string.MediaReviewFragment__too_many_items_selected, Toast.LENGTH_SHORT).show()
+        MediaValidator.FilterError.NO_ITEMS -> {}
+      }
+    }
   }
 
   private fun ensureMediaGalleryFragment(): MediaGalleryFragment {

app/src/main/java/org/thoughtcrime/securesms/mediasend/v2/review/MediaReviewFragment.kt

@@ -8,6 +8,7 @@ import android.view.View
 import android.widget.ImageView
 import android.widget.ProgressBar
 import android.widget.TextView
+import android.widget.Toast
 import android.widget.ViewSwitcher
 import androidx.activity.OnBackPressedCallback
 import androidx.constraintlayout.widget.ConstraintLayout
@@ -18,6 +19,7 @@ import androidx.fragment.app.viewModels
 import androidx.recyclerview.widget.ItemTouchHelper
 import androidx.recyclerview.widget.RecyclerView
 import androidx.viewpager2.widget.ViewPager2
+import app.cash.exhaustive.Exhaustive
 import io.reactivex.rxjava3.disposables.CompositeDisposable
 import org.thoughtcrime.securesms.R
 import org.thoughtcrime.securesms.conversation.mutiselect.forward.MultiselectForwardFragment
@@ -30,6 +32,7 @@ import org.thoughtcrime.securesms.mediasend.v2.MediaSelectionNavigator
 import org.thoughtcrime.securesms.mediasend.v2.MediaSelectionNavigator.Companion.requestPermissionsForGallery
 import org.thoughtcrime.securesms.mediasend.v2.MediaSelectionState
 import org.thoughtcrime.securesms.mediasend.v2.MediaSelectionViewModel
+import org.thoughtcrime.securesms.mediasend.v2.MediaValidator
 import org.thoughtcrime.securesms.mms.SentMediaQuality
 import org.thoughtcrime.securesms.permissions.Permissions
 import org.thoughtcrime.securesms.recipients.RecipientId
@@ -201,6 +204,19 @@ class MediaReviewFragment : Fragment(R.layout.v2_media_review_fragment) {
       computeViewStateAndAnimate(state)
     }
 
+    sharedViewModel.mediaErrors.observe(viewLifecycleOwner) { error: MediaValidator.FilterError ->
+      @Exhaustive
+      when (error) {
+        MediaValidator.FilterError.ITEM_TOO_LARGE -> Toast.makeText(requireContext(), R.string.MediaReviewFragment__one_or_more_items_were_too_large, Toast.LENGTH_SHORT).show()
+        MediaValidator.FilterError.ITEM_INVALID_TYPE -> Toast.makeText(requireContext(), R.string.MediaReviewFragment__one_or_more_items_were_invalid, Toast.LENGTH_SHORT).show()
+        MediaValidator.FilterError.TOO_MANY_ITEMS -> Toast.makeText(requireContext(), R.string.MediaReviewFragment__too_many_items_selected, Toast.LENGTH_SHORT).show()
+        MediaValidator.FilterError.NO_ITEMS -> {
+          Toast.makeText(requireContext(), R.string.MediaReviewFragment__one_or_more_items_were_invalid, Toast.LENGTH_SHORT).show()
+          callback.onNoMediaSelected()
+        }
+      }
+    }
+
     requireActivity().onBackPressedDispatcher.addCallback(
       viewLifecycleOwner,
       object : OnBackPressedCallback(true) {
@@ -449,6 +465,7 @@ class MediaReviewFragment : Fragment(R.layout.v2_media_review_fragment) {
     fun onSentWithResult(mediaSendActivityResult: MediaSendActivityResult)
     fun onSentWithoutResult()
     fun onSendError(error: Throwable)
+    fun onNoMediaSelected()
     fun onPopFromReview()
   }
 }

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

@@ -3822,6 +3822,9 @@
     <string name="MediaReviewFragment__add_a_reply">Add a reply</string>
     <string name="MediaReviewFragment__send_to">Send to</string>
     <string name="MediaReviewFragment__view_once_message">View once message</string>
+    <string name="MediaReviewFragment__one_or_more_items_were_too_large">One or more items were too large</string>
+    <string name="MediaReviewFragment__one_or_more_items_were_invalid">One or more items were invalid</string>
+    <string name="MediaReviewFragment__too_many_items_selected">Too many items selected</string>
 
     <string name="ImageEditorHud__cancel">Cancel</string>
     <string name="ImageEditorHud__draw">Draw</string>