an implementation of wxListBox::SetFirstItem() which seems to work

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@8602 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/gtk/listbox.cpp

@@ -416,16 +416,16 @@ int wxListBox::DoAppend( const wxString& item )
         // need to determine the index
         int index = m_strings->Add( item );
 
-	// only if not at the end anyway
+        // only if not at the end anyway
-	if (index != GetCount())
+        if (index != GetCount())
-	{
+        {
-	   GtkAddItem( item, index );
+           GtkAddItem( item, index );
 
-	   wxNode *node = m_clientList.Nth( index );
+           wxNode *node = m_clientList.Nth( index );
            m_clientList.Insert( node, (wxObject *)NULL );
 
-	   return index;
+           return index;
-	}
+        }
     }
 
     GtkAddItem(item);
@@ -492,7 +492,7 @@ void wxListBox::GtkAddItem( const wxString &item, int pos )
 
         // Apply current widget style to the new list_item
         if (m_widgetStyle)
-	{
+        {
             gtk_widget_set_style( GTK_WIDGET( list_item ), m_widgetStyle );
             GtkBin *bin = GTK_BIN( list_item );
             GtkWidget *label = GTK_WIDGET( bin->child );
@@ -778,9 +778,44 @@ void wxListBox::SetSelection( int n, bool select )
     GtkEnableEvents();
 }
 
-void wxListBox::DoSetFirstItem( int WXUNUSED(n) )
+void wxListBox::DoSetFirstItem( int n )
 {
-    wxFAIL_MSG(wxT("wxListBox::SetFirstItem not implemented"));
+    wxCHECK_RET( m_list, wxT("invalid listbox") );
+
+    if (gdk_pointer_is_grabbed () && GTK_WIDGET_HAS_GRAB (m_list))
+        return;
+
+    // terribly efficient
+    const gchar *vadjustment_key = "gtk-vadjustment";
+    guint vadjustment_key_id = g_quark_from_static_string (vadjustment_key);
+
+    GtkAdjustment *adjustment =
+       (GtkAdjustment*) gtk_object_get_data_by_id (GTK_OBJECT (m_list), vadjustment_key_id);
+    wxCHECK_RET( adjustment, wxT("invalid listbox code") );
+
+    GList *target = g_list_nth( m_list->children, n );
+    wxCHECK_RET( target, wxT("invalid listbox index") );
+    
+    GtkWidget *item = GTK_WIDGET(target->data);
+    wxCHECK_RET( item, wxT("invalid listbox code") );
+
+    // find the last item before this one which is already realized
+    size_t nItemsBefore;
+    for ( nItemsBefore = 0; item && (item->allocation.y == -1); nItemsBefore++ )
+    {
+        target = target->prev;
+        if ( !target )
+        {
+            // nothing we can do if there are no allocated items yet
+            return;
+        }
+
+        item = GTK_WIDGET(target->data);
+    }
+
+    gtk_adjustment_set_value(adjustment,
+                             item->allocation.y +
+                                nItemsBefore*item->allocation.height);
 }
 
 // ----------------------------------------------------------------------------

src/gtk1/listbox.cpp

@@ -416,16 +416,16 @@ int wxListBox::DoAppend( const wxString& item )
         // need to determine the index
         int index = m_strings->Add( item );
 
-	// only if not at the end anyway
+        // only if not at the end anyway
-	if (index != GetCount())
+        if (index != GetCount())
-	{
+        {
-	   GtkAddItem( item, index );
+           GtkAddItem( item, index );
 
-	   wxNode *node = m_clientList.Nth( index );
+           wxNode *node = m_clientList.Nth( index );
            m_clientList.Insert( node, (wxObject *)NULL );
 
-	   return index;
+           return index;
-	}
+        }
     }
 
     GtkAddItem(item);
@@ -492,7 +492,7 @@ void wxListBox::GtkAddItem( const wxString &item, int pos )
 
         // Apply current widget style to the new list_item
         if (m_widgetStyle)
-	{
+        {
             gtk_widget_set_style( GTK_WIDGET( list_item ), m_widgetStyle );
             GtkBin *bin = GTK_BIN( list_item );
             GtkWidget *label = GTK_WIDGET( bin->child );
@@ -778,9 +778,44 @@ void wxListBox::SetSelection( int n, bool select )
     GtkEnableEvents();
 }
 
-void wxListBox::DoSetFirstItem( int WXUNUSED(n) )
+void wxListBox::DoSetFirstItem( int n )
 {
-    wxFAIL_MSG(wxT("wxListBox::SetFirstItem not implemented"));
+    wxCHECK_RET( m_list, wxT("invalid listbox") );
+
+    if (gdk_pointer_is_grabbed () && GTK_WIDGET_HAS_GRAB (m_list))
+        return;
+
+    // terribly efficient
+    const gchar *vadjustment_key = "gtk-vadjustment";
+    guint vadjustment_key_id = g_quark_from_static_string (vadjustment_key);
+
+    GtkAdjustment *adjustment =
+       (GtkAdjustment*) gtk_object_get_data_by_id (GTK_OBJECT (m_list), vadjustment_key_id);
+    wxCHECK_RET( adjustment, wxT("invalid listbox code") );
+
+    GList *target = g_list_nth( m_list->children, n );
+    wxCHECK_RET( target, wxT("invalid listbox index") );
+    
+    GtkWidget *item = GTK_WIDGET(target->data);
+    wxCHECK_RET( item, wxT("invalid listbox code") );
+
+    // find the last item before this one which is already realized
+    size_t nItemsBefore;
+    for ( nItemsBefore = 0; item && (item->allocation.y == -1); nItemsBefore++ )
+    {
+        target = target->prev;
+        if ( !target )
+        {
+            // nothing we can do if there are no allocated items yet
+            return;
+        }
+
+        item = GTK_WIDGET(target->data);
+    }
+
+    gtk_adjustment_set_value(adjustment,
+                             item->allocation.y +
+                                nItemsBefore*item->allocation.height);
 }
 
 // ----------------------------------------------------------------------------