Fix setting colours for the edit control part of wxComboBox.

Recognize this control as part of wxComboBox and so handle WM_CTLCOLOR for it.

To do this, override ContainsHWND() in wxComboBox and use it, on the parent
window, in wxControl::DoMSWControlColor(), if we fail to find the window
directly.

Closes #811.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@72468 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

docs/changes.txt

@@ -557,6 +557,7 @@ wxGTK:
 
 wxMSW:
 
+- Fix setting colours for the text part of wxComboBox (Igor Korot).
 - Add support for CURRENCY and SCODE types to OLE Automation helpers (PB).
 - Allow setting LCID used by wxAutomationObject (PB).
 - Fix calling Iconize(false) on hidden top level windows (Christian Walther).

include/wx/msw/combobox.h

@@ -92,6 +92,7 @@ public:
     virtual void SetSelection(long from, long to)
         { wxTextEntry::SetSelection(from, to); }
     virtual int GetSelection() const { return wxChoice::GetSelection(); }
+    virtual bool ContainsHWND(WXHWND hWnd) const;
     virtual void GetSelection(long *from, long *to) const;
 
     virtual bool IsEditable() const;

src/msw/combobox.cpp

@@ -550,6 +550,11 @@ void wxComboBox::Clear()
         wxTextEntry::Clear();
 }
 
+bool wxComboBox::ContainsHWND(WXHWND hWnd) const
+{
+    return hWnd == GetEditHWNDIfAvailable();
+}
+
 void wxComboBox::GetSelection(long *from, long *to) const
 {
     if ( !HasFlag(wxCB_READONLY) )

src/msw/control.cpp

@@ -367,7 +367,23 @@ WXHBRUSH wxControl::DoMSWControlColor(WXHDC pDC, wxColour colBg, WXHWND hWnd)
     WXHBRUSH hbr = 0;
     if ( !colBg.IsOk() )
     {
-        if ( wxWindow *win = wxFindWinFromHandle(hWnd) )
+        wxWindow *win = wxFindWinFromHandle( hWnd );
+        if ( !win )
+        {
+            // If this HWND doesn't correspond to a wxWindow, it still might be
+            // one of its children for which we need to set the background
+            // brush, e.g. this is the case for the EDIT control that is part
+            // of wxComboBox. Check for this by asking the parent if it has it:
+            HWND parent = ::GetParent(hWnd);
+            if ( parent )
+            {
+                wxWindow *winParent = wxFindWinFromHandle( parent );
+                if( winParent && winParent->ContainsHWND( hWnd ) )
+                    win = winParent;
+             }
+        }
+
+        if ( win )
             hbr = win->MSWGetBgBrush(pDC);
 
         // if the control doesn't have any bg colour, foreground colour will be