Dear pros,

I've created combobox with this :

Code:
{
    xtype:'combobox',
    id: 'comboMasterDepartemen',
    emptyText: 'No records',
    name: 'cmb1',
    allowBlank: true,
    fieldLabel: 'Parent Org. ',
    store: new Ext.data.Store({
        autoLoad: true,
        fields: ['id_departemen', 'nm_departemen'],
        proxy: {
            type: 'ajax',
            url : 'master_departemen/master_departemen/data/3',
            reader: {
                type: 'json',
                root : 'dataRecords'
            }
        },
        listeners: {
            load: function () {
                var combo = Ext.getCmp('comboMasterDepartemen');
                 combo.clearValue();
                 combo.applyEmptyText();
                if(this.getCount()>0) { combo.setValue(this.first().data.id_departemen); }
            }
        }
    }),
    editable: false,
    displayField: 'nm_departemen',
    valueField: 'id_departemen',
    labelAlign: 'right',
    anchor:'100%'
}
How do i get the combobox object within Store without defining " Ext.getCmp('comboMasterDepartemen'); " explicitly, so i dont have to define " id " prop in combobox.

Thanx