<?xml version="1.0" encoding="utf-8"?>
<!-- http://blog.flexexamples.com/2007/11/21/allowing-multiple-selected-items-in-flex-list-and-datagrid-controls/ -->
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"
        layout="horizontal"
        verticalAlign="middle"
        backgroundColor="white">

    <mx:Array id="arr">
        <mx:Object col1="One.1" col2="One.2" col3="One.3" />
        <mx:Object col1="Two.1" col2="Two.2" col3="Two.3" />
        <mx:Object col1="Three.1" col2="Three.2" col3="Three.3" />
        <mx:Object col1="Four.1" col2="Four.2" col3="Four.3" />
        <mx:Object col1="Five.1" col2="Five.2" col3="Five.3" />
        <mx:Object col1="Six.1" col2="Six.2" col3="Six.3" />
        <mx:Object col1="Seven.1" col2="Seven.2" col3="Seven.3" />
        <mx:Object col1="Eight.1" col2="Eight.2" col3="Eight.3" />
    </mx:Array>

    <mx:ApplicationControlBar dock="true">
        <mx:Form styleName="plain">
            <mx:FormItem label="allowMultipleSelection:">
                <mx:CheckBox id="checkBox" selected="true" />
            </mx:FormItem>
        </mx:Form>
    </mx:ApplicationControlBar>

    <mx:List id="list"
            allowMultipleSelection="{checkBox.selected}"
            dataProvider="{arr}"
            labelField="col1"
            verticalScrollPolicy="on" />

    <mx:DataGrid id="dataGrid"
            allowMultipleSelection="{checkBox.selected}"
            dataProvider="{arr}"
            verticalScrollPolicy="on" />

</mx:Application>

