Ask for confirmation if the user quit the screen before creating the room

vector/src/main/java/im/vector/app/features/roomdirectory/createroom/CreateRoomFragment.kt

@@ -19,6 +19,7 @@ package im.vector.app.features.roomdirectory.createroom
 import android.net.Uri
 import android.os.Bundle
 import android.view.View
+import androidx.appcompat.app.AlertDialog
 import com.airbnb.mvrx.Success
 import com.airbnb.mvrx.activityViewModel
 import com.airbnb.mvrx.withState
@@ -26,18 +27,20 @@ import im.vector.app.R
 import im.vector.app.core.dialogs.GalleryOrCameraDialogHelper
 import im.vector.app.core.extensions.cleanup
 import im.vector.app.core.extensions.configureWith
+import im.vector.app.core.extensions.exhaustive
 import im.vector.app.core.platform.OnBackPressed
 import im.vector.app.core.platform.VectorBaseFragment
 import im.vector.app.core.resources.ColorProvider
 import im.vector.app.features.roomdirectory.RoomDirectorySharedAction
 import im.vector.app.features.roomdirectory.RoomDirectorySharedActionViewModel
+import im.vector.app.features.roomprofile.settings.RoomSettingsAction
 import kotlinx.android.synthetic.main.fragment_create_room.*
 import timber.log.Timber
 import javax.inject.Inject
 
 class CreateRoomFragment @Inject constructor(
         private val createRoomController: CreateRoomController,
-        private val colorProvider: ColorProvider
+        colorProvider: ColorProvider
 ) : VectorBaseFragment(),
         CreateRoomController.Listener,
         GalleryOrCameraDialogHelper.Listener,
@@ -58,6 +61,11 @@ class CreateRoomFragment @Inject constructor(
         createRoomClose.debouncedClicks {
             sharedActionViewModel.post(RoomDirectorySharedAction.Back)
         }
+        viewModel.observeViewEvents {
+            when (it) {
+                CreateRoomViewEvents.Quit -> vectorBaseActivity.onBackPressed()
+            }.exhaustive
+        }
     }
 
     override fun onDestroyView() {
@@ -113,9 +121,21 @@ class CreateRoomFragment @Inject constructor(
     }
 
     override fun onBackPressed(toolbarButton: Boolean): Boolean {
-        // TODO BMA, as per the other PR, ask the user if he has started to input elements before leaving the screen
+        return withState(viewModel) {
-        viewModel.handle(CreateRoomAction.Reset)
+            return@withState if (!it.isEmpty()) {
-        return false
+                AlertDialog.Builder(requireContext())
+                        .setTitle(R.string.dialog_title_warning)
+                        .setMessage(R.string.warning_room_not_created_yet)
+                        .setPositiveButton(R.string.yes) { _, _ ->
+                            viewModel.handle(CreateRoomAction.Reset)
+                        }
+                        .setNegativeButton(R.string.no, null)
+                        .show()
+                true
+            } else {
+                false
+            }
+        }
     }
 
     override fun invalidate() = withState(viewModel) { state ->

vector/src/main/java/im/vector/app/features/roomdirectory/createroom/CreateRoomViewEvents.kt

@@ -0,0 +1,26 @@
+/*
+ * Copyright (c) 2020 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package im.vector.app.features.roomdirectory.createroom
+
+import im.vector.app.core.platform.VectorViewEvents
+
+/**
+ * Transient events for room creation screen
+ */
+sealed class CreateRoomViewEvents : VectorViewEvents {
+    object Quit : CreateRoomViewEvents()
+}

vector/src/main/java/im/vector/app/features/roomdirectory/createroom/CreateRoomViewModel.kt

@@ -28,7 +28,6 @@ import com.airbnb.mvrx.ViewModelContext
 import com.squareup.inject.assisted.Assisted
 import com.squareup.inject.assisted.AssistedInject
 import im.vector.app.core.extensions.exhaustive
-import im.vector.app.core.platform.EmptyViewEvents
 import im.vector.app.core.platform.VectorViewModel
 import im.vector.app.features.raw.wellknown.getElementWellknown
 import im.vector.app.features.raw.wellknown.isE2EByDefault
@@ -46,7 +45,7 @@ import org.matrix.android.sdk.api.session.room.model.create.CreateRoomPreset
 class CreateRoomViewModel @AssistedInject constructor(@Assisted initialState: CreateRoomViewState,
                                                       private val session: Session,
                                                       private val rawService: RawService
-) : VectorViewModel<CreateRoomViewState, CreateRoomAction, EmptyViewEvents>(initialState) {
+) : VectorViewModel<CreateRoomViewState, CreateRoomAction, CreateRoomViewEvents>(initialState) {
 
     @AssistedInject.Factory
     interface Factory {
@@ -113,6 +112,8 @@ class CreateRoomViewModel @AssistedInject constructor(@Assisted initialState: Cr
                     hsAdminHasDisabledE2E = !adminE2EByDefault
             )
         }
+
+        _viewEvents.post(CreateRoomViewEvents.Quit)
     }
 
     private fun setAvatar(action: CreateRoomAction.SetAvatar) = setState { copy(avatarUri = action.imageUri) }

vector/src/main/java/im/vector/app/features/roomdirectory/createroom/CreateRoomViewState.kt

@@ -30,4 +30,10 @@ data class CreateRoomViewState(
         val isEncrypted: Boolean = false,
         val hsAdminHasDisabledE2E: Boolean = false,
         val asyncCreateRoomRequest: Async<String> = Uninitialized
-) : MvRxState
+) : MvRxState {
+
+    /**
+     * Return true if there is not important input from user
+     */
+    fun isEmpty() = avatarUri == null && roomName.isEmpty() && roomTopic.isEmpty()
+}

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

@@ -2632,6 +2632,7 @@
 
     <!-- Universal link -->
     <string name="universal_link_malformed">The link was malformed</string>
+    <string name="warning_room_not_created_yet">The room is not yet created. Cancel the room creation?</string>
     <string name="warning_unsaved_change">There are unsaved changes. Discard the changes?</string>
     <string name="warning_unsaved_change_discard">Discard changes</string>
 </resources>