为什么你用brackground而不是icon属性？图标是动态的还是静态的？

.hidden {
    display: none
}

和工作样品：

Ext.create('Ext.data.Store', {
    storeId: 'employeeStore',
    fields: ['firstname', 'lastname', 'seniority', 'dep', 'hired'],
    data: [{
        firstname: "Michael",
        lastname: "Scott"
    }, {
        firstname: "Dwight",
        lastname: "Schrute"
    }, {
        firstname: "Jim",
        lastname: "Halpert"
    }, {
        firstname: "Kevin",
        lastname: "Malone"
    }, {
        firstname: "Angela",
        lastname: "Martin"
    }]
});

Ext.create('Ext.grid.Panel', {
    title: 'Action Column Demo',
    store: Ext.data.StoreManager.lookup('employeeStore'),
    columns: [{
        text: 'First Name',
        dataIndex: 'firstname'
    }, {
        text: 'Last Name',
        dataIndex: 'lastname'
    }, {
        xtype: 'actioncolumn',
        width: 50,
        items: [{
            icon: 'https://docs.sencha.com/extjs/4.2.6/extjs-build/examples/shared/icons/fam/cog_edit.png', // Use a URL in the icon config
            tooltip: 'Edit',
            hidden: true,
            getClass: function (value, metaData, record, rowIndex) {
                if (rowIndex % 2) {
                    return 'hidden'
                }
            },
            handler: function (grid, rowIndex, colIndex) {
                var rec = grid.getStore().getAt(rowIndex);
                alert("Edit " + rec.get('firstname'));
            }
        }]
    }],
    width: 250,
    renderTo: Ext.getBody()
});