Launch tools from Idle in the kicad manager.

Launching on a control event can allow that control to steal focus from the new windows as more events may exist intended for the control.

Fix #4479

kicad/tree_project_frame.cpp

@@ -131,6 +131,7 @@ BEGIN_EVENT_TABLE( TREE_PROJECT_FRAME, wxSashLayoutWindow )
     EVT_MENU( ID_PROJECT_DELETE, TREE_PROJECT_FRAME::OnDeleteFile )
     EVT_MENU( ID_PROJECT_PRINT, TREE_PROJECT_FRAME::OnPrintFile )
     EVT_MENU( ID_PROJECT_RENAME, TREE_PROJECT_FRAME::OnRenameFile )
+    EVT_IDLE( TREE_PROJECT_FRAME::OnIdle )
 END_EVENT_TABLE()
 
 
@@ -141,6 +142,7 @@ TREE_PROJECT_FRAME::TREE_PROJECT_FRAME( KICAD_MANAGER_FRAME* parent ) :
     m_Parent = parent;
     m_TreeProject = NULL;
     m_isRenaming = false;
+    m_selectedItem = nullptr;
 
     m_watcher = NULL;
     Connect( wxEVT_FSWATCHER,
@@ -905,7 +907,22 @@ void TREE_PROJECT_FRAME::OnSelect( wxTreeEvent& Event )
     if( tree_data.size() != 1 )
         return;
 
-    tree_data[0]->Activate( this );
+    // Bookmark the selected item but don't try and activate it until later
+    // if we do it now, there will be more events at least on Windows in this frame
+    // that will steal focus from any newly launched windows
+    m_selectedItem = tree_data[0];
+}
+
+
+void TREE_PROJECT_FRAME::OnIdle( wxIdleEvent& aEvent )
+{
+    // Idle executes once all other events finished processing
+    // This makes it ideal to launch a new window without starting Focus wars.
+    if( m_selectedItem != nullptr )
+    {
+        m_selectedItem->Activate( this );
+        m_selectedItem = nullptr;
+    }
 }
 
 

kicad/tree_project_frame.h

@@ -57,6 +57,7 @@ private:
     wxTreeItemId            m_root;
     std::vector<wxString>   m_filters;
     wxFileSystemWatcher*    m_watcher; // file system watcher
+    TREEPROJECT_ITEM*       m_selectedItem;
 
 public:
     TREE_PROJECT_FRAME( KICAD_MANAGER_FRAME* parent );
@@ -158,6 +159,12 @@ private:
      */
     void OnSwitchToSelectedProject( wxCommandEvent& event );
 
+    /**
+     * Idle event handler, used process the selected items at a point in time
+     * when all other events have been consumed
+     */
+    void OnIdle( wxIdleEvent &aEvent );
+
     /**
      * Function AddItemToTreeProject
      * @brief  Add the file or directory aName to the project tree