Fix crash on attachment preview screen (#1088)

CHANGES.md

@@ -8,7 +8,7 @@ Improvements 🙌:
  -
 
 Bugfix 🐛:
- -
+ - Fix crash on attachment preview screen (#1088)
 
 Translations 🗣:
  -

vector/src/main/java/im/vector/riotx/features/attachments/preview/AttachmentsPreviewFragment.kt

@@ -39,6 +39,7 @@ import com.airbnb.mvrx.fragmentViewModel
 import com.airbnb.mvrx.withState
 import com.yalantis.ucrop.UCrop
 import com.yalantis.ucrop.UCropActivity
+import im.vector.matrix.android.api.extensions.orFalse
 import im.vector.matrix.android.api.session.content.ContentAttachmentData
 import im.vector.riotx.R
 import im.vector.riotx.core.extensions.cleanup
@@ -115,7 +116,7 @@ class AttachmentsPreviewFragment @Inject constructor(
     override fun onPrepareOptionsMenu(menu: Menu) {
         withState(viewModel) { state ->
             val editMenuItem = menu.findItem(R.id.attachmentsPreviewEditAction)
-            val showEditMenuItem = state.attachments[state.currentAttachmentIndex].isEditable()
+            val showEditMenuItem = state.attachments.getOrNull(state.currentAttachmentIndex)?.isEditable().orFalse()
             editMenuItem.setVisible(showEditMenuItem)
         }