space switcher empty spaces (#6988)

changelog.d/6754.bugfix

@@ -0,0 +1 @@
+[App Layout] - space switcher now has empty state

library/ui-strings/src/main/res/values/strings.xml

@@ -442,6 +442,10 @@
     <string name="system_alerts_header">"System Alerts"</string>
     <string name="suggested_header">Suggested Rooms</string>
 
+    <!-- Space List fragment -->
+    <string name="space_list_empty_title">No spaces yet.</string>
+    <string name="space_list_empty_message">Spaces are a new way to group rooms and people. Create a space to get started.</string>
+
     <!-- Invites fragment -->
     <string name="invites_title">Invites</string>
 

vector/src/main/java/im/vector/app/features/spaces/SpaceListFragment.kt

@@ -21,6 +21,7 @@ import android.view.HapticFeedbackConstants
 import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
+import androidx.core.view.isVisible
 import com.airbnb.epoxy.EpoxyTouchHelper
 import com.airbnb.mvrx.Loading
 import com.airbnb.mvrx.Success
@@ -28,6 +29,7 @@ import com.airbnb.mvrx.Uninitialized
 import com.airbnb.mvrx.fragmentViewModel
 import com.airbnb.mvrx.withState
 import dagger.hilt.android.AndroidEntryPoint
+import im.vector.app.core.epoxy.onClick
 import im.vector.app.core.extensions.cleanup
 import im.vector.app.core.extensions.configureWith
 import im.vector.app.core.platform.StateView
@@ -71,6 +73,7 @@ class SpaceListFragment :
         homeActivitySharedActionViewModel = activityViewModelProvider[HomeSharedActionViewModel::class.java]
         roomListSharedActionViewModel = activityViewModelProvider[RoomListSharedActionViewModel::class.java]
         views.stateView.contentView = views.groupListView
+        views.spacesEmptyButton.onClick { onAddSpaceSelected() }
         setupSpaceController()
         observeViewEvents()
     }
@@ -147,13 +150,22 @@ class SpaceListFragment :
     }
 
     override fun invalidate() = withState(viewModel) { state ->
-        when (state.asyncSpaces) {
+        when (val spaces = state.asyncSpaces) {
             Uninitialized,
             is Loading -> {
                 views.stateView.state = StateView.State.Loading
                 return@withState
             }
-            is Success -> views.stateView.state = StateView.State.Content
+            is Success -> {
+                views.stateView.state = StateView.State.Content
+                if (spaces.invoke().isEmpty()) {
+                    views.spacesEmptyGroup.isVisible = true
+                    views.groupListView.isVisible = false
+                } else {
+                    views.spacesEmptyGroup.isVisible = false
+                    views.groupListView.isVisible = true
+                }
+            }
             else -> Unit
         }
 

vector/src/main/res/layout/fragment_space_list.xml

@@ -12,4 +12,48 @@
         android:overScrollMode="always"
         tools:listitem="@layout/item_space" />
 
+
+    <LinearLayout
+        android:id="@+id/spaces_empty_group"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_gravity="center"
+        android:orientation="vertical"
+        android:padding="@dimen/layout_horizontal_margin"
+        android:visibility="gone"
+        tools:visibility="visible">
+
+        <TextView
+            android:id="@+id/spaces_empty_title"
+            style="@style/Widget.Vector.TextView.Subtitle"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_gravity="center_horizontal"
+            android:gravity="center"
+            android:text="@string/space_list_empty_title"
+            android:textColor="?vctr_content_primary"
+            android:textStyle="bold" />
+
+        <TextView
+            android:id="@+id/spaces_empty_message"
+            style="@style/Widget.Vector.TextView.Body"
+            android:layout_width="220dp"
+            android:layout_height="wrap_content"
+            android:layout_gravity="center"
+            android:layout_marginTop="20dp"
+            android:gravity="center"
+            android:text="@string/space_list_empty_message"
+            android:textColor="?vctr_content_secondary" />
+
+        <Button
+            android:id="@+id/spaces_empty_button"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_gravity="center"
+            android:layout_marginTop="8dp"
+            android:minWidth="190dp"
+            android:text="@string/create_space" />
+
+    </LinearLayout>
+
 </im.vector.app.core.platform.StateView>