wx_grid.cpp

Go to the documentation of this file.

/*
 * This program source code file is part of KiCad, a free EDA CAD application.
 *
 * Copyright (C) 2018-2023 KiCad Developers, see AUTHORS.txt for contributors.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 3
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, you may find one here:
 * http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
 * or you may search the http://www.gnu.org website for the version 2 license,
 * or you may write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
 */
 
#include <wx/colour.h>
#include <wx/tokenzr.h>
#include <wx/dc.h>
#include <wx/settings.h>
#include <wx/event.h> // Needed for textentry.h on MSW
#include <wx/textentry.h>
 
#include <widgets/wx_grid.h>
#include <widgets/ui_common.h>
#include <algorithm>
#include <core/kicad_algo.h>
#include <gal/color4d.h>
#include <kiplatform/ui.h>
 
#include <pgm_base.h>
#include <settings/common_settings.h>
 
 
wxGridCellAttr* WX_GRID_TABLE_BASE::enhanceAttr( wxGridCellAttr* aInputAttr, int aRow, int aCol,
 wxGridCellAttr::wxAttrKind aKind )
{
 wxGridCellAttr* attr = aInputAttr;
 
 if( wxGridCellAttrProvider* provider = GetAttrProvider() )
 {
 wxGridCellAttr* providerAttr = provider->GetAttr( aRow, aCol, aKind );
 
 if( providerAttr )
 {
 attr = new wxGridCellAttr;
 attr->SetKind( wxGridCellAttr::Merged );
 
 if( aInputAttr )
 {
 attr->MergeWith( aInputAttr );
 aInputAttr->DecRef();
 }
 
 attr->MergeWith( providerAttr );
 providerAttr->DecRef();
 }
 }
 
 return attr;
}
 
 
#define MIN_GRIDCELL_MARGIN FromDIP( 3 )
 
 
void WX_GRID::CellEditorSetMargins( wxTextEntryBase* aEntry )
{
 // This is consistent with wxGridCellTextEditor. But works differently across platforms or course.
 aEntry->SetMargins( 0, 0 );
}
 
 
void WX_GRID::CellEditorTransformSizeRect( wxRect& aRect )
{
#if defined( __WXMSW__ ) || defined( __WXGTK__ )
 aRect.Deflate( 2 );
#endif
}
 
 
wxColour getBorderColour()
{
 KIGFX::COLOR4D bg = wxSystemSettings::GetColour( wxSYS_COLOUR_FRAMEBK );
 KIGFX::COLOR4D fg = wxSystemSettings::GetColour( wxSYS_COLOUR_ACTIVEBORDER );
 KIGFX::COLOR4D border = fg.Mix( bg, 0.50 );
 return border.ToColour();
}
 
 
class WX_GRID_CORNER_HEADER_RENDERER : public wxGridCornerHeaderRendererDefault
{
public:
 void DrawBorder( const wxGrid& grid, wxDC& dc, wxRect& rect ) const override
 {
 wxDCBrushChanger SetBrush( dc, *wxTRANSPARENT_BRUSH );
 wxDCPenChanger SetPen( dc, wxPen( getBorderColour(), 1 ) );
 
 rect.SetTop( rect.GetTop() + 1 );
 rect.SetLeft( rect.GetLeft() + 1 );
 rect.SetBottom( rect.GetBottom() - 1 );
 rect.SetRight( rect.GetRight() - 1 );
 dc.DrawRectangle( rect );
 }
};
 
 
class WX_GRID_COLUMN_HEADER_RENDERER : public wxGridColumnHeaderRendererDefault
{
public:
 void DrawBorder( const wxGrid& grid, wxDC& dc, wxRect& rect ) const override
 {
 wxDCBrushChanger SetBrush( dc, *wxTRANSPARENT_BRUSH );
 wxDCPenChanger SetPen( dc, wxPen( getBorderColour(), 1 ) );
 
 rect.SetTop( rect.GetTop() + 1 );
 rect.SetLeft( rect.GetLeft() );
 rect.SetBottom( rect.GetBottom() - 1 );
 rect.SetRight( rect.GetRight() - 1 );
 dc.DrawRectangle( rect );
 }
};
 
 
class WX_GRID_ROW_HEADER_RENDERER : public wxGridRowHeaderRendererDefault
{
public:
 void DrawBorder( const wxGrid& grid, wxDC& dc, wxRect& rect ) const override
 {
 wxDCBrushChanger SetBrush( dc, *wxTRANSPARENT_BRUSH );
 wxDCPenChanger SetPen( dc, wxPen( getBorderColour(), 1 ) );
 
 rect.SetTop( rect.GetTop() + 1 );
 rect.SetLeft( rect.GetLeft() + 1 );
 rect.SetBottom( rect.GetBottom() - 1 );
 rect.SetRight( rect.GetRight() );
 dc.DrawRectangle( rect );
 }
};
 
 
class WX_GRID_ALT_ROW_COLOR_PROVIDER : public wxGridCellAttrProvider
{
public:
 WX_GRID_ALT_ROW_COLOR_PROVIDER( const wxColor& aBaseColor ) : wxGridCellAttrProvider(),
 m_attrOdd( new wxGridCellAttr() )
 {
 UpdateColors( aBaseColor );
 }
 
 
 void UpdateColors( const wxColor& aBaseColor )
 {
 // Choose the default color, taking into account if the dark mode theme is enabled
 wxColor rowColor = aBaseColor.ChangeLightness( KIPLATFORM::UI::IsDarkTheme() ? 105 : 95 );
 
 m_attrOdd->SetBackgroundColour( rowColor );
 }
 
 
 wxGridCellAttr* GetAttr( int row, int col,
 wxGridCellAttr::wxAttrKind kind ) const override
 {
 wxGridCellAttrPtr cellAttr( wxGridCellAttrProvider::GetAttr( row, col, kind ) );
 
 // Just pass through the cell attribute on even rows
 if( row % 2 )
 return cellAttr.release();
 
 if( !cellAttr )
 {
 cellAttr = m_attrOdd;
 }
 else
 {
 if( !cellAttr->HasBackgroundColour() )
 {
 cellAttr = cellAttr->Clone();
 cellAttr->SetBackgroundColour( m_attrOdd->GetBackgroundColour() );
 }
 }
 
 return cellAttr.release();
 }
 
private:
 wxGridCellAttrPtr m_attrOdd;
};
 
 
WX_GRID::WX_GRID( wxWindow *parent, wxWindowID id, const wxPoint& pos, const wxSize& size,
 long style, const wxString& name ) :
 wxGrid( parent, id, pos, size, style, name ),
 m_weOwnTable( false )
{
 SetDefaultCellOverflow( false );
 
 // Make sure the GUI font scales properly
 SetDefaultCellFont( KIUI::GetControlFont( this ) );
 SetLabelFont( KIUI::GetControlFont( this ) );
 
 if( GetColLabelSize() > 0 )
 SetColLabelSize( GetColLabelSize() + FromDIP( 4 ) );
 
 Connect( wxEVT_DPI_CHANGED, wxDPIChangedEventHandler( WX_GRID::onDPIChanged ), nullptr, this );
 Connect( wxEVT_GRID_EDITOR_SHOWN, wxGridEventHandler( WX_GRID::onCellEditorShown ), nullptr, this );
 Connect( wxEVT_GRID_EDITOR_HIDDEN, wxGridEventHandler( WX_GRID::onCellEditorHidden ), nullptr, this );
}
 
 
WX_GRID::~WX_GRID()
{
 if( m_weOwnTable )
 DestroyTable( GetTable() );
 
 Disconnect( wxEVT_GRID_EDITOR_SHOWN, wxGridEventHandler( WX_GRID::onCellEditorShown ), nullptr, this );
 Disconnect( wxEVT_GRID_EDITOR_HIDDEN, wxGridEventHandler( WX_GRID::onCellEditorHidden ), nullptr, this );
 Disconnect( wxEVT_DPI_CHANGED, wxDPIChangedEventHandler( WX_GRID::onDPIChanged ), nullptr, this );
}
 
 
void WX_GRID::onDPIChanged(wxDPIChangedEvent& aEvt)
{
#ifndef __WXMAC__
 aEvt.Skip();
#endif
}
 
 
void WX_GRID::SetColLabelSize( int aHeight )
{
 if( aHeight == 0 )
 {
 wxGrid::SetColLabelSize( 0 );
 return;
 }
 
 // Correct wxFormBuilder height for large fonts
 int minHeight = GetLabelFont().GetPixelSize().y + 2 * MIN_GRIDCELL_MARGIN;
 wxGrid::SetColLabelSize( std::max( aHeight, minHeight ) );
}
 
 
void WX_GRID::SetLabelFont( const wxFont& aFont )
{
 wxGrid::SetLabelFont( KIUI::GetControlFont( this ) );
}
 
 
void WX_GRID::SetTable( wxGridTableBase* aTable, bool aTakeOwnership )
{
 // wxGrid::SetTable() messes up the column widths from wxFormBuilder so we have to save
 // and restore them.
 int numberCols = GetNumberCols();
 int* formBuilderColWidths = new int[numberCols];
 
 for( int i = 0; i < numberCols; ++i )
 formBuilderColWidths[ i ] = GetColSize( i );
 
 wxGrid::SetTable( aTable );
 
 // wxGrid::SetTable() may change the number of columns, so prevent out-of-bounds access
 // to formBuilderColWidths
 numberCols = std::min( numberCols, GetNumberCols() );
 
 for( int i = 0; i < numberCols; ++i )
 {
 // correct wxFormBuilder width for large fonts and/or long translations
 int headingWidth = GetTextExtent( GetColLabelValue( i ) ).x + 2 * MIN_GRIDCELL_MARGIN;
 
 SetColSize( i, std::max( formBuilderColWidths[ i ], headingWidth ) );
 }
 
 delete[] formBuilderColWidths;
 
 EnableAlternateRowColors( Pgm().GetCommonSettings()->m_Appearance.grid_striping );
 
 Connect( wxEVT_GRID_COL_MOVE, wxGridEventHandler( WX_GRID::onGridColMove ), nullptr, this );
 Connect( wxEVT_GRID_SELECT_CELL, wxGridEventHandler( WX_GRID::onGridCellSelect ), nullptr, this );
 
 m_weOwnTable = aTakeOwnership;
}
 
 
void WX_GRID::EnableAlternateRowColors( bool aEnable )
{
 wxGridTableBase* table = wxGrid::GetTable();
 
 wxCHECK_MSG( table, /* void */,
 "Tried to enable alternate row colors without a table assigned to the grid" );
 
 if( aEnable )
 {
 wxColor color = wxGrid::GetDefaultCellBackgroundColour();
 table->SetAttrProvider( new WX_GRID_ALT_ROW_COLOR_PROVIDER( color ) );
 }
 else
 {
 table->SetAttrProvider( nullptr );
 }
}
 
 
void WX_GRID::onGridCellSelect( wxGridEvent& aEvent )
{
 // Highlight the selected cell.
 // Calling SelectBlock() allows a visual effect when cells are selected by tab or arrow keys.
 // Otherwise, one cannot really know what actual cell is selected.
 int row = aEvent.GetRow();
 int col = aEvent.GetCol();
 
 if( row >= 0 && row < GetNumberRows() && col >= 0 && col < GetNumberCols() )
 {
 if( GetSelectionMode() == wxGrid::wxGridSelectCells )
 {
 SelectBlock( row, col, row, col, false );
 }
 else if( GetSelectionMode() == wxGrid::wxGridSelectRows
 || GetSelectionMode() == wxGrid::wxGridSelectRowsOrColumns )
 {
 SelectBlock( row, 0, row, GetNumberCols() - 1, false );
 }
 else if( GetSelectionMode() == wxGrid::wxGridSelectColumns )
 {
 SelectBlock( 0, col, GetNumberRows() - 1, col, false );
 }
 }
}
 
 
void WX_GRID::onCellEditorShown( wxGridEvent& aEvent )
{
 if( alg::contains( m_autoEvalCols, aEvent.GetCol() ) )
 {
 int row = aEvent.GetRow();
 int col = aEvent.GetCol();
 
 const std::pair<wxString, wxString>& beforeAfter = m_evalBeforeAfter[ { row, col } ];
 
 if( GetCellValue( row, col ) == beforeAfter.second )
 SetCellValue( row, col, beforeAfter.first );
 }
}
 
 
void WX_GRID::onCellEditorHidden( wxGridEvent& aEvent )
{
 if( alg::contains( m_autoEvalCols, aEvent.GetCol() ) )
 {
 UNITS_PROVIDER* unitsProvider = m_unitsProviders[ aEvent.GetCol() ];
 
 if( !unitsProvider )
 unitsProvider = m_unitsProviders.begin()->second;
 
 m_eval->SetDefaultUnits( unitsProvider->GetUserUnits() );
 
 int row = aEvent.GetRow();
 int col = aEvent.GetCol();
 
 CallAfter(
 [this, row, col, unitsProvider]()
 {
 wxString stringValue = GetCellValue( row, col );
 
 if( m_eval->Process( stringValue ) )
 {
 int val = unitsProvider->ValueFromString( m_eval->Result() );
 wxString evalValue = unitsProvider->StringFromValue( val, true );
 
 if( stringValue != evalValue )
 {
 SetCellValue( row, col, evalValue );
 m_evalBeforeAfter[ { row, col } ] = { stringValue, evalValue };
 }
 }
 } );
 }
 
 aEvent.Skip();
}
 
 
void WX_GRID::DestroyTable( wxGridTableBase* aTable )
{
 // wxGrid's destructor will crash trying to look up the cell attr if the edit control
 // is left open. Normally it's closed in Validate(), but not if the user hit Cancel.
 CommitPendingChanges( true /* quiet mode */ );
 
 Disconnect( wxEVT_GRID_COL_MOVE, wxGridEventHandler( WX_GRID::onGridColMove ), nullptr, this );
 Disconnect( wxEVT_GRID_SELECT_CELL, wxGridEventHandler( WX_GRID::onGridCellSelect ), nullptr, this );
 
 wxGrid::SetTable( nullptr );
 delete aTable;
}
 
 
wxString WX_GRID::GetShownColumnsAsString()
{
 wxString shownColumns;
 
 for( int i = 0; i < GetNumberCols(); ++i )
 {
 if( IsColShown( i ) )
 {
 if( shownColumns.Length() )
 shownColumns << wxT( " " );
 
 shownColumns << i;
 }
 }
 
 return shownColumns;
}
 
 
std::bitset<64> WX_GRID::GetShownColumns()
{
 std::bitset<64> shownColumns;
 
 for( int ii = 0; ii < GetNumberCols(); ++ii )
 shownColumns[ii] = IsColShown( ii );
 
 return shownColumns;
}
 
 
void WX_GRID::ShowHideColumns( const wxString& shownColumns )
{
 for( int i = 0; i < GetNumberCols(); ++i )
 HideCol( i );
 
 wxStringTokenizer shownTokens( shownColumns );
 
 while( shownTokens.HasMoreTokens() )
 {
 long colNumber;
 shownTokens.GetNextToken().ToLong( &colNumber );
 
 if( colNumber >= 0 && colNumber < GetNumberCols() )
 ShowCol( (int) colNumber );
 }
}
 
 
void WX_GRID::ShowHideColumns( const std::bitset<64>& aShownColumns )
{
 for( int ii = 0; ii < GetNumberCols(); ++ ii )
 {
 if( aShownColumns[ii] )
 ShowCol( ii );
 else
 HideCol( ii );
 }
}
 
 
void WX_GRID::DrawCornerLabel( wxDC& dc )
{
 if( m_nativeColumnLabels )
 wxGrid::DrawCornerLabel( dc );
 
 wxRect rect( wxSize( m_rowLabelWidth, m_colLabelHeight ) );
 
 static WX_GRID_CORNER_HEADER_RENDERER rend;
 
 // It is reported that we need to erase the background to avoid display
 // artifacts, see #12055.
 {
 wxDCBrushChanger setBrush( dc, m_colLabelWin->GetBackgroundColour() );
 wxDCPenChanger setPen( dc, m_colLabelWin->GetBackgroundColour() );
 dc.DrawRectangle( rect.Inflate( 1 ) );
 }
 
 rend.DrawBorder( *this, dc, rect );
}
 
 
void WX_GRID::DrawColLabel( wxDC& dc, int col )
{
 if( m_nativeColumnLabels )
 wxGrid::DrawColLabel( dc, col );
 
 if( GetColWidth( col ) <= 0 || m_colLabelHeight <= 0 )
 return;
 
 wxRect rect( GetColLeft( col ), 0, GetColWidth( col ), m_colLabelHeight );
 
 static WX_GRID_COLUMN_HEADER_RENDERER rend;
 
 // It is reported that we need to erase the background to avoid display
 // artifacts, see #12055.
 {
 wxDCBrushChanger setBrush( dc, m_colLabelWin->GetBackgroundColour() );
 wxDCPenChanger setPen( dc, m_colLabelWin->GetBackgroundColour() );
 dc.DrawRectangle( rect.Inflate( 1 ) );
 }
 
 rend.DrawBorder( *this, dc, rect );
 
 // Make sure fonts get scaled correctly on GTK HiDPI monitors
 dc.SetFont( GetLabelFont() );
 
 int hAlign, vAlign;
 GetColLabelAlignment( &hAlign, &vAlign );
 const int orient = GetColLabelTextOrientation();
 
 if( col == 0 )
 hAlign = wxALIGN_LEFT;
 
 if( hAlign == wxALIGN_LEFT )
 rect.SetLeft( rect.GetLeft() + MIN_GRIDCELL_MARGIN );
 
 rend.DrawLabel( *this, dc, GetColLabelValue( col ), rect, hAlign, vAlign, orient );
}
 
 
void WX_GRID::DrawRowLabel( wxDC& dc, int row )
{
 if ( GetRowHeight( row ) <= 0 || m_rowLabelWidth <= 0 )
 return;
 
 wxRect rect( 0, GetRowTop( row ), m_rowLabelWidth, GetRowHeight( row ) );
 
 static WX_GRID_ROW_HEADER_RENDERER rend;
 
 // It is reported that we need to erase the background to avoid display
 // artifacts, see #12055.
 {
 wxDCBrushChanger setBrush( dc, m_colLabelWin->GetBackgroundColour() );
 wxDCPenChanger setPen( dc, m_colLabelWin->GetBackgroundColour() );
 dc.DrawRectangle( rect.Inflate( 1 ) );
 }
 
 rend.DrawBorder( *this, dc, rect );
 
 // Make sure fonts get scaled correctly on GTK HiDPI monitors
 dc.SetFont( GetLabelFont() );
 
 int hAlign, vAlign;
 GetRowLabelAlignment(&hAlign, &vAlign);
 
 if( hAlign == wxALIGN_LEFT )
 rect.SetLeft( rect.GetLeft() + MIN_GRIDCELL_MARGIN );
 
 rend.DrawLabel( *this, dc, GetRowLabelValue( row ), rect, hAlign, vAlign, wxHORIZONTAL );
}
 
 
bool WX_GRID::CancelPendingChanges()
{
 if( !IsCellEditControlEnabled() )
 return true;
 
 HideCellEditControl();
 
 // do it after HideCellEditControl()
 m_cellEditCtrlEnabled = false;
 
 int row = m_currentCellCoords.GetRow();
 int col = m_currentCellCoords.GetCol();
 
 wxString oldval = GetCellValue( row, col );
 wxString newval;
 
 wxGridCellAttr* attr = GetCellAttr( row, col );
 wxGridCellEditor* editor = attr->GetEditor( this, row, col );
 
 editor->EndEdit( row, col, this, oldval, &newval );
 
 editor->DecRef();
 attr->DecRef();
 
 return true;
}
 
 
bool WX_GRID::CommitPendingChanges( bool aQuietMode )
{
 if( !IsCellEditControlEnabled() )
 return true;
 
 if( !aQuietMode && SendEvent( wxEVT_GRID_EDITOR_HIDDEN ) == -1 )
 return false;
 
 HideCellEditControl();
 
 // do it after HideCellEditControl()
 m_cellEditCtrlEnabled = false;
 
 int row = m_currentCellCoords.GetRow();
 int col = m_currentCellCoords.GetCol();
 
 wxString oldval = GetCellValue( row, col );
 wxString newval;
 
 wxGridCellAttr* attr = GetCellAttr( row, col );
 wxGridCellEditor* editor = attr->GetEditor( this, row, col );
 
 bool changed = editor->EndEdit( row, col, this, oldval, &newval );
 
 editor->DecRef();
 attr->DecRef();
 
 if( changed )
 {
 if( !aQuietMode && SendEvent( wxEVT_GRID_CELL_CHANGING, newval ) == -1 )
 return false;
 
 editor->ApplyEdit( row, col, this );
 
 // for compatibility reasons dating back to wx 2.8 when this event
 // was called wxEVT_GRID_CELL_CHANGE and wxEVT_GRID_CELL_CHANGING
 // didn't exist we allow vetoing this one too
 if( !aQuietMode && SendEvent( wxEVT_GRID_CELL_CHANGED, oldval ) == -1 )
 {
 // Event has been vetoed, set the data back.
 SetCellValue( row, col, oldval );
 return false;
 }
 }
 
 return true;
}
 
 
void WX_GRID::SetUnitsProvider( UNITS_PROVIDER* aProvider, int aCol )
{
 m_unitsProviders[ aCol ] = aProvider;
 
 if( !m_eval )
 m_eval = std::make_unique<NUMERIC_EVALUATOR>( aProvider->GetUserUnits() );
}
 
 
int WX_GRID::GetUnitValue( int aRow, int aCol )
{
 UNITS_PROVIDER* unitsProvider = m_unitsProviders[ aCol ];
 
 if( !unitsProvider )
 unitsProvider = m_unitsProviders.begin()->second;
 
 wxString stringValue = GetCellValue( aRow, aCol );
 
 if( alg::contains( m_autoEvalCols, aCol ) )
 {
 m_eval->SetDefaultUnits( unitsProvider->GetUserUnits() );
 
 if( m_eval->Process( stringValue ) )
 stringValue = m_eval->Result();
 }
 
 return unitsProvider->ValueFromString( stringValue );
}
 
 
void WX_GRID::SetUnitValue( int aRow, int aCol, int aValue )
{
 UNITS_PROVIDER* unitsProvider = m_unitsProviders[ aCol ];
 
 if( !unitsProvider )
 unitsProvider = m_unitsProviders.begin()->second;
 
 SetCellValue( aRow, aCol, unitsProvider->StringFromValue( aValue, true ) );
}
 
 
void WX_GRID::onGridColMove( wxGridEvent& aEvent )
{
 // wxWidgets won't move an open editor, so better just to close it
 CommitPendingChanges( true );
}
 
 
int WX_GRID::GetVisibleWidth( int aCol, bool aHeader, bool aContents, bool aKeep )
{
 int size = 0;
 
 if( aCol < 0 )
 {
 if( aKeep )
 size = GetRowLabelSize();
 
 for( int row = 0; aContents && row < GetNumberRows(); row++ )
 size = std::max( size, int( GetTextExtent( GetRowLabelValue( row ) + wxS( "M" ) ).x ) );
 }
 else
 {
 if( aKeep )
 size = GetColSize( aCol );
 
 // 'M' is generally the widest character, so we buffer the column width by default to
 // ensure we don't write a continuous line of text at the column header
 if( aHeader )
 {
 EnsureColLabelsVisible();
 
 size = std::max( size, int( GetTextExtent( GetColLabelValue( aCol ) + wxS( "M" ) ).x ) );
 }
 
 for( int row = 0; aContents && row < GetNumberRows(); row++ )
 {
 // If we have text, get the size. Otherwise, use a placeholder for the checkbox
 if( GetTable()->CanGetValueAs( row, aCol, wxGRID_VALUE_STRING ) )
 size = std::max( size, GetTextExtent( GetCellValue( row, aCol ) + wxS( "M" ) ).x );
 else
 size = std::max( size, GetTextExtent( "MM" ).x );
 }
 }
 
 return size;
}
 
 
void WX_GRID::EnsureColLabelsVisible()
{
 int line_height = int( GetTextExtent( "Mj" ).y ) + 3;
 int row_height = GetColLabelSize();
 int initial_row_height = row_height;
 
 // Headers can be multiline. Fix the Column Label Height to show the full header
 // However GetTextExtent does not work on multiline strings,
 // and do not return the full text height (only the height of one line)
 for( int col = 0; col < GetNumberCols(); col++ )
 {
 int nl_count = GetColLabelValue( col ).Freq( '\n' );
 
 if( nl_count )
 {
 // Col Label height must be able to show nl_count+1 lines
 if( row_height < line_height * ( nl_count+1 ) )
 row_height += line_height * nl_count;
 }
 }
 
 // Update the column label size, but only if needed, to avoid generating useless
 // and perhaps annoying UI events when the size does not change
 if( initial_row_height != row_height )
 SetColLabelSize( row_height );
}