For the ease of access here's the answer from the other question:
You can set a default value for the combo. That should then get that rendered at startup.
Use cell renderer to render the displayField of the combo into your grid. Following a working example that can be poster in one of the API code boxes
Working JSFiddle
Ext.create('Ext.data.Store', {
storeId:'simpsonsStore',
fields:['name', 'email', 'phone', 'id'],
data:{'items':[
{"name":"Lisa", "email":"[email protected]", "phone":"555-111-1224","id": 0},
{"name":"Bart", "email":"[email protected]", "phone":"555-222-1234","id": 1},
{"name":"Homer", "email":"[email protected]", "phone":"555-222-1244","id": 2},
{"name":"Marge", "email":"[email protected]", "phone":"555-222-1254","id": 3}
]},
proxy: {
type: 'memory',
reader: {
type: 'json',
root: 'items'
}
}
});
// the renderer. You should define it within a namespace
var comboBoxRenderer = function(combo) {
return function(value) {
var idx = combo.store.find(combo.valueField, value);
var rec = combo.store.getAt(idx);
return (rec === null ? '' : rec.get(combo.displayField) );
};
}
// the combo store
var store = new Ext.data.SimpleStore({
fields: [ "value", "text" ],
data: [
[ 1, "Option 1" ],
[ 2, "Option 2" ]
]
});
// the edit combo
var combo = new Ext.form.ComboBox({
store: store,
valueField: "value",
displayField: "text"
});
// demogrid
Ext.create('Ext.grid.Panel', {
title: 'Simpsons',
store: Ext.data.StoreManager.lookup('simpsonsStore'),
columns: [
{header: 'Name', dataIndex: 'name', editor: 'textfield'},
{header: 'Email', dataIndex: 'email', flex:1,
editor: {
xtype: 'textfield',
allowBlank: false
}
},
{header: 'Phone', dataIndex: 'phone'},
{header: 'id', dataIndex: 'id', editor: combo, renderer: comboBoxRenderer(combo)}
],
selType: 'cellmodel',
plugins: [
Ext.create('Ext.grid.plugin.CellEditing', {
clicksToEdit: 1
})
],
height: 200,
width: 400,
renderTo: Ext.getBody()
});