How to get a value from controller to form - extjs

Question

I've built a master/detail form in ExtJS4 as an exercise of learning ExtJS.
I want to pass down id from master table to the detail form when i'm creating a new article.
When the create button is pressed in detailGrid, the id is passed to the controller. In the controller I can see the output of the id via console.log so I know it is present in the controller.
How can I pass it to the form?
Controller:
{
var detailgrid = button.up('userdetail');
var parentId = detailgrid.getParentId();
console.log(parentId);
var view = Ext.widget('detailadd');
},
The Form where I need to get parentId from the controller
Ext.define('calsberg.view.user.DetailsAdd', {
extend: 'Ext.window.Window',
alias: 'widget.detailadd',
title: 'Add Artikli',
config:
{
parentId: parentId
},
layout: 'fit',
autoShow: true,
initComponent: function () {
this.items = [
{
xtype: 'form',
bodyStyle: {
background: 'none',
padding: '10px',
border: '0'
},
items: [
{
xtype: 'textfield',
name: 'parentId',
value: this.getParentId()
},
{
xtype: 'textfield',
name: 'sifra',
allowBlank: false,
fieldLabel: 'Šifra'
},
{
xtype: 'textfield',
name: 'naziv',
allowBlank: false,
vtype: 'naziv',
fieldLabel: 'Naziv'
},

Answer 1

You can either put the variable in the global namespace so that you can reference it from anywhere in the App e.g.
// MyApp would already be initialised in app.js
MyApp.parentId = detailgrid.getParentId();
// then you could reference it anywhere else thereafter
Ext.define('calsberg.view.user.DetailsAdd', {
extend: 'Ext.window.Window',
alias: 'widget.detailadd',
title: 'Add Artikli',
config:
{
parentId: MyApp.parentId
}
.....
Or you could pass in a config object when you create the widget such as this
var detailgrid = button.up('userdetail');
var parentId = detailgrid.getParentId();
console.log(parentId);
var view = Ext.widget('detailadd', {config:{parentId:parentId}});