add icon, still needs color-correction for dark theme

Signed-off-by: Jonas Mayer <jonas.a.mayer@gmx.net>

app/src/main/java/com/owncloud/android/ui/adapter/UploadListAdapter.java

@@ -102,7 +102,14 @@ public class UploadListAdapter extends SectionedRecyclerViewAdapter<SectionedVie
                           group.getGroupName(), group.getGroupItemCount()));
         viewThemeUtils.platform.colorPrimaryTextViewElement(headerViewHolder.binding.uploadListTitle);
 
-        headerViewHolder.binding.uploadListTitle.setOnClickListener(v -> toggleSectionExpanded(section));
+        headerViewHolder.binding.uploadListTitle.setOnClickListener(v -> {
+            if(isSectionExpanded(section)){
+                headerViewHolder.binding.uploadListState.setImageResource(R.drawable.ic_expand_less);
+            } else {
+                headerViewHolder.binding.uploadListState.setImageResource(R.drawable.ic_expand_more);
+            }
+            toggleSectionExpanded(section);
+        });
 
         switch (group.type) {
             case CURRENT, FINISHED -> headerViewHolder.binding.uploadListAction.setImageResource(R.drawable.ic_close);

app/src/main/res/layout/upload_list_header.xml

@@ -14,12 +14,24 @@
     android:layout_height="wrap_content"
     android:orientation="horizontal">
 
+    <ImageView
+        android:id="@+id/upload_list_state"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_alignParentStart="true"
+        android:contentDescription="@string/delete_entries"
+        android:paddingStart="@dimen/zero"
+        android:paddingTop="@dimen/standard_half_padding"
+        android:paddingEnd="@dimen/standard_half_padding"
+        android:paddingBottom="@dimen/standard_half_padding"
+        android:src="@drawable/ic_expand_less" />
+
     <TextView
         android:id="@+id/upload_list_title"
         style="@style/TextAppearance.AppCompat.Body2"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
-        android:layout_alignParentStart="true"
+        android:layout_toEndOf="@id/upload_list_state"
         android:layout_toStartOf="@id/upload_list_action"
         android:ellipsize="middle"
         android:padding="@dimen/standard_half_padding"