#5568: Streamline the resource tree view filter functions a bit.

This way the code to hide empty folders can also take effect when overriding the IsTreeModelRowVisible method.

libs/wxutil/dataview/ResourceTreeView.cpp

@@ -102,10 +102,8 @@ void ResourceTreeView::SetupTreeModelFilter()
     // Set up the filter
     _treeModelFilter.reset(new TreeModelFilter(_treeStore));
 
-    _treeModelFilter->SetVisibleFunc([this](TreeModel::Row& row)
-    {
-        return IsTreeModelRowVisible(row);
-    });
+    _treeModelFilter->SetVisibleFunc(
+        std::bind(&ResourceTreeView::IsTreeModelRowOrAnyChildVisible, this, std::placeholders::_1));
 
     AssociateModel(_treeModelFilter.get());
 
@@ -596,73 +594,56 @@ bool ResourceTreeView::IsFavouriteSelected()
     return row[_columns.isFavourite].getBool();
 }
 
-bool ResourceTreeView::IsTreeModelRowVisible(wxutil::TreeModel::Row& row)
-{
-    if (!IsTreeModelRowVisibleByViewMode(row))
-    {
-        return false; // done here
-    }
-
-    // Check for a text filter we might need to apply
-    if (_filterText.empty())
-    {
-        return true; // done here
-    }
-
-    return !IsTreeModelRowFilteredRecursively(row);
-}
-
-bool ResourceTreeView::IsTreeModelRowFilteredRecursively(wxutil::TreeModel::Row& row)
+bool ResourceTreeView::IsTreeModelRowOrAnyChildVisible(TreeModel::Row& row)
 {
-    if (TreeModel::RowContainsString(row, _filterText, _colsToSearch, true))
+    // Test the node itself
+    if (IsTreeModelRowVisible(row))
     {
-        return false;
+        return true; // node is visible
     }
 
-    // This node might also be visible if a single child node is visible, dive into it
+    // The node itself is invisible, but it might still be visible
+    // if any of the child nodes is visible, dive into it
     wxDataViewItemArray children;
     _treeStore->GetChildren(row.getItem(), children);
 
     for (const wxDataViewItem& child : children)
     {
         wxutil::TreeModel::Row childRow(child, *_treeStore);
 
-        if (!IsTreeModelRowFilteredRecursively(childRow))
+        // Check the child node (recursively)
+        if (IsTreeModelRowOrAnyChildVisible(childRow))
         {
-            return false; // unfiltered node, break the loop
+            return true; // found a visible child, this is enough
         }
     }
 
     // Either we don't have any children, or 
-    // all child nodes are filtered, so this node is filtered too
-    return true;
+    // all child nodes are invisible, so this node is invisible too
+    return false;
 }
 
-bool ResourceTreeView::IsTreeModelRowVisibleByViewMode(wxutil::TreeModel::Row& row)
+bool ResourceTreeView::IsTreeModelRowVisible(wxutil::TreeModel::Row& row)
 {
-    if (_mode == TreeMode::ShowAll) return true; // everything is visible
-
-    // Favourites mode, check if this item or any descendant is visible
-    if (row[_columns.isFavourite].getBool())
+    // Check view mode
+    if (!IsTreeModelRowVisibleByViewMode(row))
     {
-        return true;
+        return false; // done here
     }
 
-    wxDataViewItemArray children;
-    _treeStore->GetChildren(row.getItem(), children);
-
-    // Enter the recursion for each of the children and bail out on the first visible one
-    for (const wxDataViewItem& child : children)
-    {
-        wxutil::TreeModel::Row childRow(child, *_treeStore);
+    // Check filter, otherwise the node is visible
+    return !IsTreeModelRowFiltered(row);
+}
 
-        if (IsTreeModelRowVisibleByViewMode(childRow))
-        {
-            return true;
-        }
-    }
+bool ResourceTreeView::IsTreeModelRowFiltered(wxutil::TreeModel::Row& row)
+{
+    return !_filterText.empty() && !TreeModel::RowContainsString(row, _filterText, _colsToSearch, true);
+}
 
-    return false;
+bool ResourceTreeView::IsTreeModelRowVisibleByViewMode(wxutil::TreeModel::Row& row)
+{
+    // In favourites mode, check if this item is marked as favourite
+    return _mode == TreeMode::ShowAll || row[_columns.isFavourite].getBool();
 }
 
 }

libs/wxutil/dataview/ResourceTreeView.h

@@ -173,12 +173,15 @@ class ResourceTreeView :
     virtual std::string GetResourcePathOfSelection();
 
 private:
+    // Recursive visibility test used by the TreeModelFilterFunction
+    bool IsTreeModelRowOrAnyChildVisible(TreeModel::Row& row);
+
     // Returns true if the given row is visible according 
     // to the current view mode (show favourites vs. show all)
     bool IsTreeModelRowVisibleByViewMode(TreeModel::Row& row);
 
-    // Returns true if the given row is filtered (i.e. node and all child nodes are invisible)
-    bool IsTreeModelRowFilteredRecursively(wxutil::TreeModel::Row& row);
+    // Returns true if the given row is filtered by an active filter text
+    bool IsTreeModelRowFiltered(wxutil::TreeModel::Row& row);
 
     void _onContextMenu(wxDataViewEvent& ev);
     void _onTreeStorePopulationProgress(TreeModel::PopulationProgressEvent& ev);