From dc4f639c61e1790677912a666cea324047212bfd Mon Sep 17 00:00:00 2001
From: Jeff Young <jeff@rokeby.ie>
Date: Mon, 14 Jul 2025 22:46:35 +0100
Subject: [PATCH] Make sure selected item is still valid before activating
 (KICAD-18S).

---
 kicad/project_tree.cpp      | 14 ++++++++++++++
 kicad/project_tree.h        |  2 ++
 kicad/project_tree_pane.cpp | 30 ++++++++++++++++++++----------
 3 files changed, 36 insertions(+), 10 deletions(-)

diff --git a/kicad/project_tree.cpp b/kicad/project_tree.cpp
index 8c5832a6b7..d53918a045 100644
--- a/kicad/project_tree.cpp
+++ b/kicad/project_tree.cpp
@@ -208,6 +208,20 @@ void PROJECT_TREE::LoadIcons()
 }
 
 
+void PROJECT_TREE::GetItemsRecursively( const wxTreeItemId& aParentId, std::vector<wxTreeItemId>& aItems )
+{
+    wxTreeItemIdValue cookie;
+    wxTreeItemId      child = GetFirstChild( aParentId, cookie );
+
+    while( child.IsOk() )
+    {
+        aItems.push_back( child );
+        GetItemsRecursively( child, aItems );
+        child = GetNextChild( aParentId, cookie );
+    }
+}
+
+
 int PROJECT_TREE::OnCompareItems( const wxTreeItemId& item1, const wxTreeItemId& item2 )
 {
     PROJECT_TREE_ITEM* myitem1 = (PROJECT_TREE_ITEM*) GetItemData( item1 );
diff --git a/kicad/project_tree.h b/kicad/project_tree.h
index f9174b3d78..dc0d469894 100644
--- a/kicad/project_tree.h
+++ b/kicad/project_tree.h
@@ -57,6 +57,8 @@ public:
 
     void LoadIcons();
 
+    void GetItemsRecursively( const wxTreeItemId& aParentId, std::vector<wxTreeItemId>& aItems );
+
     void SetGitRepo( git_repository* aRepo )    { m_gitCommon->SetRepo( aRepo ); }
     git_repository* GetGitRepo() const          { return m_gitCommon->GetRepo(); }
 
diff --git a/kicad/project_tree_pane.cpp b/kicad/project_tree_pane.cpp
index 93d393c2dd..8dd0d7e615 100644
--- a/kicad/project_tree_pane.cpp
+++ b/kicad/project_tree_pane.cpp
@@ -1177,12 +1177,23 @@ void PROJECT_TREE_PANE::onIdle( wxIdleEvent& aEvent )
 
     if( m_selectedItem != nullptr )
     {
-        // Activate launches a window which may run the event loop on top of us and cause OnIdle
-        // to get called again, so be sure to block off the activation condition first.
-        PROJECT_TREE_ITEM* item = m_selectedItem;
-        m_selectedItem          = nullptr;
+        // Make sure m_selectedItem still exists in the tree before activating it.
+        std::vector<wxTreeItemId> validItemIds;
+        m_TreeProject->GetItemsRecursively( m_TreeProject->GetRootItem(), validItemIds );
 
-        item->Activate( this );
+        for( wxTreeItemId id : validItemIds )
+        {
+            if( GetItemIdData( id ) == m_selectedItem )
+            {
+                // Activate launches a window which may run the event loop on top of us and cause
+                // onIdle to get called again, so be sure to null out m_selectedItem first.
+                PROJECT_TREE_ITEM* item = m_selectedItem;
+                m_selectedItem          = nullptr;
+
+                item->Activate( this );
+                break;
+            }
+        }
     }
 }
 
@@ -1254,19 +1265,18 @@ void PROJECT_TREE_PANE::onExpand( wxTreeEvent& Event )
 
 std::vector<PROJECT_TREE_ITEM*> PROJECT_TREE_PANE::GetSelectedData()
 {
-    wxArrayTreeItemIds             selection;
+    wxArrayTreeItemIds              selection;
     std::vector<PROJECT_TREE_ITEM*> data;
 
     m_TreeProject->GetSelections( selection );
 
-    for( auto it = selection.begin(); it != selection.end(); it++ )
+    for( const wxTreeItemId itemId : selection )
     {
-        PROJECT_TREE_ITEM* item = GetItemIdData( *it );
+        PROJECT_TREE_ITEM* item = GetItemIdData( itemId );
 
         if( !item )
         {
-            wxLogTrace( traceGit, wxS( "Null tree item returned for selection, dynamic_cast "
-                                       "failed?" ) );
+            wxLogTrace( traceGit, wxS( "Null tree item returned for selection, dynamic_cast failed?" ) );
             continue;
         }