destroy window when list nets dialog is closed

avoid potential performance issues when the dialog is still listening to
the board updates and refreshing its data and view structures.

it seems useful to keep the settings of the dialog across dialog
open-close cycles.

pcbnew/dialogs/dialog_select_net_from_list.cpp

@@ -119,7 +119,8 @@ struct DIALOG_SELECT_NET_FROM_LIST::ROW_DESC
 };
 
 
-DIALOG_SELECT_NET_FROM_LIST::DIALOG_SELECT_NET_FROM_LIST( PCB_EDIT_FRAME* aParent )
+DIALOG_SELECT_NET_FROM_LIST::DIALOG_SELECT_NET_FROM_LIST(
+        PCB_EDIT_FRAME* aParent, const SETTINGS& aSettings )
         : DIALOG_SELECT_NET_FROM_LIST_BASE( aParent ), m_frame( aParent )
 {
     m_brd = aParent->GetBoard();
@@ -144,6 +145,9 @@ DIALOG_SELECT_NET_FROM_LIST::DIALOG_SELECT_NET_FROM_LIST( PCB_EDIT_FRAME* aParen
     // expander buttons... but it doesn't.  Fix by forcing the indent to 0.
     m_netsList->SetIndent( 0 );
 
+    m_textCtrlFilter->SetValue( aSettings.filter_string );
+    m_cbShowZeroPad->SetValue( aSettings.show_zero_pad_nets );
+
     buildNetsList();
 
     adjustListColumns();
@@ -181,9 +185,14 @@ DIALOG_SELECT_NET_FROM_LIST::~DIALOG_SELECT_NET_FROM_LIST()
         m_brd->RemoveListener( this );
 }
 
+DIALOG_SELECT_NET_FROM_LIST::SETTINGS DIALOG_SELECT_NET_FROM_LIST::Settings() const
+{
+    return { m_textCtrlFilter->GetValue(), m_cbShowZeroPad->IsChecked() };
+}
 
 void DIALOG_SELECT_NET_FROM_LIST::onParentWindowClosed( wxCommandEvent& event )
 {
+    Close();
     event.Skip();
 }
 

pcbnew/dialogs/dialog_select_net_from_list.h

@@ -36,9 +36,17 @@ class CN_ITEM;
 class DIALOG_SELECT_NET_FROM_LIST : public DIALOG_SELECT_NET_FROM_LIST_BASE, public BOARD_LISTENER
 {
 public:
-    DIALOG_SELECT_NET_FROM_LIST( PCB_EDIT_FRAME* aParent );
+    struct SETTINGS
+    {
+        wxString filter_string;
+        bool     show_zero_pad_nets = true;
+    };
+
+    DIALOG_SELECT_NET_FROM_LIST( PCB_EDIT_FRAME* aParent, const SETTINGS& aSettings );
     ~DIALOG_SELECT_NET_FROM_LIST();
 
+    SETTINGS Settings() const;
+
     // returns true if a net was selected, and its name in aName
     bool GetNetName( wxString& aName ) const;
 

pcbnew/tools/pcb_inspection_tool.cpp

@@ -28,7 +28,6 @@
 #include <tools/edit_tool.h>
 #include <painter.h>
 #include <connectivity/connectivity_data.h>
-#include <dialogs/dialog_select_net_from_list.h>
 #include <profile.h>
 #include "pcb_inspection_tool.h"
 
@@ -448,13 +447,37 @@ void PCB_INSPECTION_TOOL::calculateSelectionRatsnest()
 int PCB_INSPECTION_TOOL::ListNets( const TOOL_EVENT& aEvent )
 {
     if( m_listNetsDialog == nullptr )
-        m_listNetsDialog = std::make_unique<DIALOG_SELECT_NET_FROM_LIST>( m_frame );
+    {
+        m_listNetsDialog =
+                std::make_unique<DIALOG_SELECT_NET_FROM_LIST>( m_frame, m_listNetsDialogSettings );
+
+        m_listNetsDialog->Connect( wxEVT_CLOSE_WINDOW,
+                wxCommandEventHandler( PCB_INSPECTION_TOOL::onListNetsDialogClosed ), nullptr,
+                this );
+
+        m_listNetsDialog->Connect( wxEVT_BUTTON,
+                wxCommandEventHandler( PCB_INSPECTION_TOOL::onListNetsDialogClosed ), nullptr,
+                this );
+    }
 
     m_listNetsDialog->Show( true );
-
     return 0;
 }
 
+void PCB_INSPECTION_TOOL::onListNetsDialogClosed( wxCommandEvent& event )
+{
+    m_listNetsDialogSettings = m_listNetsDialog->Settings();
+
+    m_listNetsDialog->Disconnect( wxEVT_CLOSE_WINDOW,
+            wxCommandEventHandler( PCB_INSPECTION_TOOL::onListNetsDialogClosed ), nullptr, this );
+
+    m_listNetsDialog->Disconnect( wxEVT_BUTTON,
+            wxCommandEventHandler( PCB_INSPECTION_TOOL::onListNetsDialogClosed ), nullptr, this );
+
+    m_listNetsDialog->Destroy();
+    m_listNetsDialog.release();
+}
+
 void PCB_INSPECTION_TOOL::setTransitions()
 {
     Go( &PCB_INSPECTION_TOOL::CrossProbePcbToSch,     EVENTS::SelectedEvent );

pcbnew/tools/pcb_inspection_tool.h

@@ -26,12 +26,11 @@
 
 
 #include <dialogs/dialog_board_statistics.h>
+#include <dialogs/dialog_select_net_from_list.h>
 #include <pcb_edit_frame.h>
 #include <tools/pcb_actions.h>
 #include <tools/pcb_tool_base.h>
 
-class DIALOG_SELECT_NET_FROM_LIST;
-
 /**
  * PCB_INSPECTION_TOOL
  *
@@ -95,6 +94,8 @@ private:
     ///> Bind handlers to corresponding TOOL_ACTIONs
     void setTransitions() override;
 
+    void onListNetsDialogClosed( wxCommandEvent& event );
+
 private:
     PCB_EDIT_FRAME* m_frame;    // Pointer to the currently used edit frame.
 
@@ -105,6 +106,7 @@ private:
     wxTimer m_ratsnestTimer;    // Timer to initiate lazy ratsnest calculation (ie: when slow)
 
     std::unique_ptr<DIALOG_SELECT_NET_FROM_LIST> m_listNetsDialog;
+    DIALOG_SELECT_NET_FROM_LIST::SETTINGS        m_listNetsDialogSettings;
 };
 
 #endif //__BOARD_STATISTICS_TOOL_H