Make wxGenericColourButton DPI aware

include/wx/generic/clrpickerg.h

@@ -71,6 +71,8 @@ protected:
 
     void UpdateColour() wxOVERRIDE;
 
+    void OnDPIChanged(wxDPIChangedEvent& event);
+
     // the colour data shown in wxColourPickerCtrlGeneric
     // controls. This member is static so that all colour pickers
     // in the program share the same set of custom colours.

src/generic/clrpickerg.cpp

@@ -29,6 +29,10 @@
 #include "wx/colordlg.h"
 #include "wx/dcmemory.h"
 
+namespace // anonymous namespace
+{
+const wxSize defaultBitmapSize(60, 13);
+}
 
 // ============================================================================
 // implementation
@@ -46,8 +50,6 @@ bool wxGenericColourButton::Create( wxWindow *parent, wxWindowID id,
                         const wxSize &size, long style,
                         const wxValidator& validator, const wxString &name)
 {
-    m_bitmap = wxBitmap( 60, 13 );
-
     // create this button
     if (!wxBitmapButton::Create( parent, id, m_bitmap, pos,
                            size, style, validator, name ))
@@ -59,11 +61,14 @@ bool wxGenericColourButton::Create( wxWindow *parent, wxWindowID id,
     // and handle user clicks on it
     Bind(wxEVT_BUTTON, &wxGenericColourButton::OnButtonClick, this, GetId());
 
+    m_bitmap = wxBitmap(FromDIP(defaultBitmapSize));
     m_colour = col;
     UpdateColour();
     InitColourData();
     ms_data.SetChooseAlpha((style & wxCLRP_SHOW_ALPHA) != 0);
 
+    Bind(wxEVT_DPI_CHANGED, &wxGenericColourButton::OnDPIChanged, this);
+
     return true;
 }
 
@@ -118,6 +123,12 @@ void wxGenericColourButton::OnColourChanged(wxColourDialogEvent& ev)
     parent->ProcessWindowEvent(event);
 }
 
+void wxGenericColourButton::OnDPIChanged(wxDPIChangedEvent&WXUNUSED(event))
+{
+    m_bitmap = wxBitmap(FromDIP(defaultBitmapSize));
+    UpdateColour();
+}
+
 void wxGenericColourButton::UpdateColour()
 {
     wxMemoryDC dc(m_bitmap);
@@ -130,7 +141,12 @@ void wxGenericColourButton::UpdateColour()
         wxColour col( ~m_colour.Red(), ~m_colour.Green(), ~m_colour.Blue() );
         dc.SetTextForeground( col );
         dc.SetFont( GetFont() );
-        dc.DrawText( m_colour.GetAsString(wxC2S_HTML_SYNTAX), 0, 0 );
+
+        const wxString text = m_colour.GetAsString(wxC2S_HTML_SYNTAX);
+        const wxSize textSize = dc.GetTextExtent(text);
+        const int x = (m_bitmap.GetWidth() - textSize.GetWidth()) / 2;
+        const int y = (m_bitmap.GetHeight() - textSize.GetHeight()) / 2;
+        dc.DrawText(text, x, y);
     }
 
     dc.SelectObject( wxNullBitmap );