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Ext.Loader.setConfig({
    enabled: false
});

// app/view/Main.js
Ext.define('App.view.Main', {
    extend: 'Ext.Container',
    xtype: 'main',
    config: {
        layout: 'fit',
        items: [{
            xtype: 'draw',
            sprites: [{
                type: 'circle',
                fill: '#ff0000',
                radius: 30,
                x: 30,
                y: 30
            }]
        }]
    }
});

// app.js
Ext.application({
    name: 'App',
    requires: ['App.view.Main'],
    launch: function() {
        Ext.Viewport.add({
            xtype: 'main'
        });
    }
});