Nested Vbox and HBox in a Panel

[Hanterdro]

Hi,

I'm doing some experiments with extjs4.

I dont unterstand why this panel have no height.

I dont want to set the height by hand, because the panel should have the height of the content.

If I set in the panel a height by hand everything works fine.

Ext.define('TESTAPP.view.Viewport', {

    extend: 'Ext.container.Viewport',

    alias : 'widget.myViewport',

    layout: 'border',
    autoHeight: true,

    items: [{

        region: 'center',
        border: false,
        html: 'center',

        },{

        region: 'west',
        width:250,
        border: false,
        
        bodyPadding: 20,

        items: [{
        
            xtype: 'panel',
            margin:"0 0 20px 0",
            title: 'test title',
            layout: {
                type: 'vbox',
                align: 'stretch'
            },

            items:  [{
            
                    layout: {
                        type: 'hbox',
                        align: 'strech'
                    },
                    items: [{
                    
                        html: 'text left'
                    
                    },{
                    
                        html: 'text right'
                    }]        

        
                },{
            
                    html: "hello world"
                }]
    
        }]
        
    }]




});