autoscroll does not work with vbox layout

Question

I need align the formpanels to the center, so I used the vbox layout, and after I used it the autoscroll did not work as before, the code is as below:

 Usr.VWPanel = Ext.extend(Ext.Panel, {
        id: null,
        rid: null,
        closable: true,
        autoScroll: true,
        buttonAlign: 'center',
        layout: {
                type:'vbox',
                padding:'5',
                pack:'center',
                align:'center'
        },
        initComponent: function () {
            Ext.apply(this, {
                items: [
                {
                    xtype: 'spacer',
                    height: 16
                },
                {
                    xtype: 'usr.usrform',
                    itemId: 'usr.vwpain.usrformt',
                    width: 600,
                    height: 500
                },
                {
                    xtype:'spacer',
                    height: 16
                },
                {
                    xtype: 'usr.loginform',
                    itemId: 'usr.vwpain.loginform',
                    width: 600
                },
                {
                    xtype: 'spacer',
                    height: 16
                },
                {
                    xtype: 'usr.subsform',
                    itemId: 'usr.vwpain.subsform',
                    width: 600
                }],
...

plz advise.

Answer 1

the vbox layout will never show the scroller.

{
    xtype: 'window',
    title: 'My Window',
    width: 500,
    height: 500,
    layout: 'vbox',
    layoutConfig: {
        pack: 'center',
        align: 'center'
    },
    items: [
        {
            xtype: 'panel',
            title: 'My Panel',
            anchor: '80% 100%',
            height: 300,
            width: 300,
            autoScroll: true,
            items: [
                {
                    xtype: 'panel',
                    html: 'this isform1',
                    height: 100
                },
                {
                    xtype: 'panel',
                    html: 'this isform1',
                    height: 100
                },
                {
                    xtype: 'panel',
                    html: 'this isform1',
                    height: 100
                }
            ]
        }
    ]
}