I have already shown how to implement a Tree ComboBox. In the following example you can see how to implement a simpler ComboBox with a grid picker. It is implemented with support of the local and remote filtering. I have used also a calculated model field ‘fullName’ to use it as display value in the combo. You can also use as ‘displayTpl’ property to achieve the same effect.
Grouping combobox list values helps to systematize the items. This feature is already available in ‘Ext.grid.Panel’ but unfortunately not available for ‘Ext.form.field.ComboBox’. To implement the field as a single class I have changed the ‘Ext.view.BoundList’ throw ‘Ext.form.field.ComboBox:listConfig’ configuration property.