Handle units switch in board stackup.

Fixes https://gitlab.com/kicad/code/kicad/-/issues/16361

common/eda_units.cpp

@@ -602,8 +602,8 @@ double EDA_UNIT_UTILS::UI::DoubleValueFromString( const EDA_IU_SCALE& aIuScale,
             || aUnits == EDA_UNITS::MILS
             || aUnits == EDA_UNITS::INCHES )
     {
-      //check for um, μm (µ is MICRO SIGN) and µm (µ is GREEK SMALL LETTER MU) for micrometre
+        //check for um, μm (µ is MICRO SIGN) and µm (µ is GREEK SMALL LETTER MU) for micrometre
-      if( unit == wxT( "um" ) || unit == wxT( "\u00B5m" ) || unit == wxT( "\u03BCm" ) )
+        if( unit == wxT( "um" ) || unit == wxT( "\u00B5m" ) || unit == wxT( "\u03BCm" ) )
         {
             aUnits = EDA_UNITS::MICROMETRES;
         }

pcbnew/board_stackup_manager/panel_board_stackup.cpp

@@ -77,11 +77,12 @@ PANEL_SETUP_BOARD_STACKUP::PANEL_SETUP_BOARD_STACKUP( wxWindow* aParentWindow,
         PANEL_SETUP_BOARD_STACKUP_BASE( aParentWindow ),
         m_delectricMatList( DIELECTRIC_SUBSTRATE_LIST::DL_MATERIAL_DIELECTRIC ),
         m_solderMaskMatList( DIELECTRIC_SUBSTRATE_LIST::DL_MATERIAL_SOLDERMASK ),
-        m_silkscreenMatList( DIELECTRIC_SUBSTRATE_LIST::DL_MATERIAL_SILKSCREEN )
+        m_silkscreenMatList( DIELECTRIC_SUBSTRATE_LIST::DL_MATERIAL_SILKSCREEN ),
+        m_board( aFrame->GetBoard() ),
+        m_frame( aFrame ),
+        m_lastUnits( aFrame->GetUserUnits() )
 {
-    m_frame = aFrame;
     m_panelLayers = aPanelLayers;
-    m_board = m_frame->GetBoard();
     m_brdSettings = &m_board->GetDesignSettings();
 
     m_panel1->SetBorders( false, false, true, true );
@@ -118,6 +119,8 @@ PANEL_SETUP_BOARD_STACKUP::PANEL_SETUP_BOARD_STACKUP( wxWindow* aParentWindow,
     buildLayerStackPanel( true );
     synchronizeWithBoard( true );
     computeBoardThickness();
+
+    m_frame->Bind( EDA_EVT_UNITS_CHANGED, &PANEL_SETUP_BOARD_STACKUP::onUnitsChanged, this );
 }
 
 
@@ -127,6 +130,39 @@ PANEL_SETUP_BOARD_STACKUP::~PANEL_SETUP_BOARD_STACKUP()
 }
 
 
+void PANEL_SETUP_BOARD_STACKUP::onUnitsChanged( wxCommandEvent& event )
+{
+    EDA_UNITS    newUnits = m_frame->GetUserUnits();
+    EDA_IU_SCALE scale = m_frame->GetIuScale();
+
+    auto convert =
+            [&]( wxTextCtrl* aTextCtrl )
+            {
+                wxString str = aTextCtrl->GetValue();
+                long long int temp = EDA_UNIT_UTILS::UI::ValueFromString( scale, m_lastUnits, str );
+                str = EDA_UNIT_UTILS::UI::StringFromValue( scale, newUnits, temp, true );
+
+                // Don't use SetValue(); we don't want a bunch of event propagation as the actual
+                // value hasn't changed, only its presentation.
+                aTextCtrl->ChangeValue( str );
+            };
+
+    for( BOARD_STACKUP_ROW_UI_ITEM& ui_item : m_rowUiItemsList )
+    {
+        BOARD_STACKUP_ITEM* item = ui_item.m_Item;
+
+        if( item->IsThicknessEditable() && item->IsEnabled() )
+            convert( static_cast<wxTextCtrl*>( ui_item.m_ThicknessCtrl ) );
+    }
+
+    convert( m_tcCTValue );
+
+    m_lastUnits = newUnits;
+
+    event.Skip();
+}
+
+
 void PANEL_SETUP_BOARD_STACKUP::onCopperLayersSelCount( wxCommandEvent& event )
 {
     int oldBoardWidth = static_cast<int>( m_frame->ValueFromString( m_tcCTValue->GetValue() ) );

pcbnew/board_stackup_manager/panel_board_stackup.h

@@ -219,6 +219,8 @@ private:
      */
     wxBitmapComboBox* createColorBox( BOARD_STACKUP_ITEM* aStackupItem, int aRow );
 
+    void onUnitsChanged( wxCommandEvent& event );
+
     /**
      * disconnect event handlers connected to wxControl items found in list m_controlItemsList
      */
@@ -244,6 +246,7 @@ private:
     BOARD*                  m_board;
     BOARD_DESIGN_SETTINGS*  m_brdSettings;
     PCB_EDIT_FRAME*         m_frame;
+    EDA_UNITS               m_lastUnits;
     wxSize                  m_numericTextCtrlSize;  // Best size for wxTextCtrls with units
     wxSize                  m_numericFieldsSize;    // Best size for wxTextCtrls without units
     wxArrayString           m_core_prepreg_choice;  // Used to display the option list in dialog