Added pseudo-asynchronous clipboard implemenation to all ports excepts for GTK+

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@57510 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/common/clipcmn.cpp

@@ -43,10 +43,20 @@ DEFINE_EVENT_TYPE(wxEVT_CLIPBOARD_CHANGED)
 
 bool wxClipboardEvent::SupportsFormat( const wxDataFormat &format ) const
 { 
+#ifdef __WXGTK20__
+    // GTK has an asynchronnous API which reports
+    // the supported formats one by one. 
+    // We may have to add X11 and Motif later.
     wxVector<wxDataFormat>::size_type n;
     for (n = 0; n < m_formats.size(); n++)
         { if (m_formats[n] == format) return true; }
     return false;
+#else
+    // All other ports just query the clipboard directly
+    // from here
+    wxClipboard* clipboard = (wxClipboard*) GetEventObject();
+    return clipboard->IsSupported( format );
+#endif
 }     
         
 void wxClipboardEvent::AddFormat( const wxDataFormat &format ) 
@@ -69,6 +79,19 @@ static wxClipboard *gs_clipboard = NULL;
     return gs_clipboard;
 }
 
+bool wxClipboardBase::IsSupportedAsync( wxEvtHandler *sink )
+{
+    // We just imitate an asynchronous API on most platforms.
+    // This method is overridden uner GTK.
+    wxClipboardEvent *event = new wxClipboardEvent(wxEVT_CLIPBOARD_CHANGED);
+    event->SetEventObject( this );
+    
+    sink->QueueEvent( event );
+    
+    return true;
+}
+
+
 // ----------------------------------------------------------------------------
 // wxClipboardModule: module responsible for destroying the global clipboard
 // object