如何在Extjs中将视图配置链接到视图模型声明性

Ext.define('MyApp.view.MyViewModel', {
    extend: 'Ext.app.ViewModel',
    alias: 'viewmodel.myviewmodel',
    data: {
        name: 'John Doe',
        age: 30
    },
    formulas: {
        isAdult: function(get) {
            return get('age') >= 18;
        }
    }
});

Ext.define('MyApp.view.MyView', {
    extend: 'Ext.panel.Panel',
    alias: 'widget.myview',
    viewModel: 'myviewmodel',
    items: [{
        xtype: 'textfield',
        fieldLabel: 'Name',
        bind: '{name}'
    }, {
        xtype: 'numberfield',
        fieldLabel: 'Age',
        bind: '{age}'
    }, {
        xtype: 'displayfield',
        fieldLabel: 'Is Adult',
        bind: '{isAdult}'
    }]
});

Ext.define('MyApp.view.MyViewModel', {
    extend: 'Ext.app.ViewModel',
    alias: 'viewmodel.myviewmodel',
    data: {
        name: 'John Doe',
        age: 30
    },
    formulas: {
        isAdult: function(get) {
            return get('age') >= 18;
        }
    },
    links: {
        myTextField: {
            reference: 'MyApp.view.MyView',
            selector: 'textfield',
            set: {
                value: '{name}'
            }
        },
        myNumberField: {
            reference: 'MyApp.view.MyView',
            selector: 'numberfield',
            set: {
                value: '{age}'
            }
        }
    }
});