ComboBox in Modal Dialog

[alok barsode <alokbarsode gmail com>]

hi,

I want to have a Combo box in a modal dialog.

here is what I am doing :

this._combo = new PopupMenu.PopupComboBoxMenuItem({ style_class: 'status-chooser-combo' });

        this._combo.addMenuItem(new PopupMenu.PopupMenuItem("ABCD"));

        this._combo.addMenuItem(new PopupMenu.PopupMenuItem("EFGH"));

        this._combo.addMenuItem(new PopupMenu.PopupMenuItem("IJKL"));

        let act = 2;

        this._combo.setActiveItem(act);

        this._combo.setItemVisible(0, true);

        this._combo.setItemVisible(1, true);

        this._combo.setItemVisible(2, true);

        this.contentLayout.add(this._combo.actor);

I can see the ComboBox but it does not expand. If I set the ActiveItem to some other Item , the changes reflect in the ComboBox but it does not expand.

Is there something i am missing?

I am on gnome-shell ver 3.4.2.

Thanks,

Alok.