ListItem is somehow disabled again after call to enable()

So far I have this working with the code below, but when I call "me.enable()" from ListItem.updateRecord(), the dom element looks enabled (x-deckitem-disabled class is removed, isDisabled() returns false), but the item is being re-enabled somewhere after the call to updateRecord().

Can I prevent the item from being disabled? Is there a better way to do this? Possibly to bind the list item's enabled/disabled state to the 'isPurchased' value in the model?

Code:

Ext.define('Deck', {
    extend: 'Ext.data.Model',
    config: {
        fields: ['edition_title', 'game_title', 'sku', 'isPurchased', 'cards']
    }
});

Ext.define('Speakeasy.view.DeckItem', {
    extend: 'Ext.dataview.component.ListItem',
    alias: 'widget.deckitem',
    config: {
        layout: {
            type: 'vbox',
            pack: 'justify',
//            align: 'center',                                                                                      
        },
        hideAnimation: 'slideOut',
        disabled: true,
        items: [
            {
                xtype: 'component',
                itemId: 'titleCmp',
                __itemTpl: new Ext.XTemplate(
                    '<tpl for=".">',
                    '<tpl if="isPurchased">',
                    '<span class="deck-price">{price}</span>',
                    '</tpl>',
                    '</tpl>'
                ),
                docked: 'left'
            },
            {
                cls: 'buy-button-container',
                xtype: 'container',
                docked: 'right',
                items: [
                    {
                        xtype: 'button',
                        text: 'Buy',
                        itemId: 'buy-button',
                        cls: 'buy-button',
                        hideAnimation: 'fadeOut',
                        showAnimation: 'slideIn',
                        handler: function(x, e) {
                            var sku = this.up('deckitem').getRecord().get('sku');
                            decksController.Purchase(sku);
                            e.stopEvent();
                        }
                    }
                ]
            }
        ]
    },
    updateRecord: function(record) {
        var me = this;
        var buyButton = me.down('#buy-button');
        if(record.get('isPurchased')) {
            buyButton.hide();
            if(me.isDisabled())
                me.enable();
        } else {
            buyButton.show();
            if(!me.isDisabled())
                me.disabled();
        }


        if(record.get('price')) {
            buyButton.setText(record.get('price'));
        } else {
            buyButton.setText(buyButton.getInitialConfig('text'));
        }


        me.callParent(arguments);
    }
});


Ext.define('Speakeasy.view.Decks', {
    extend: 'Ext.List',
    xtype: 'decks',
    alias: 'widget.decksview',
    requires: [
        'Ext.TitleBar',
        'Ext.data.Store'
    ],
    config: {
        id: 'decksview',
        itemId: 'decksview',
        tabBarPosition: 'bottom',
        layout: {
            type: 'fit'
        },
        defaultType: 'deckitem',
//        useComponents: true,                                                                                      
        grouped: true,
        store: {
            model: 'Deck',
            sorters: 'game_title',
            fields: ['sku', 'edition_title', 'game_title'],
            grouper: {
                groupFn: function(record) {
                    var title = record.get('game_title');
                    if(title.split(' ')[0].toLowerCase().indexOf('the') == 0) {
                        return title.split(' ')[1][0];
                    } else {
                        return title[0];
                    }
                }
            },
            data: Speakeasy.DECKS_LIST
        },


        itemTpl: '{game_title}',


        items: [
            {
                docked: 'top',
                xtype: 'titlebar',
                title: 'Speakeasy',
                // items: {                                                                                         
                //     xtype: 'button',                                                                             
                //     text: 'Log Off',                                                                             
                //     itemId: 'logOffButton',                                                                      
                //     align: 'right'                                                                               
                // }                                                                                                
            }
        ],


        listeners: [
            {
                delegate: '#logOffButton',
                event: 'tap',
                fn: 'onLogOffButtonTap'
            }
        ]
    },


    initialize: function() {
        this.callParent(arguments);
        // this is here to still allow a click to the child buy button
        this.addBeforeListener('select', function(list, model, x, y, z) {
            if(model.get('isPurchased') == false)
                return false;
        });
    },


    onLogOffButtonTap: function() {
        this.fireEvent('signOffCommand');
    }
});

ListItem is somehow disabled again after call to enable()