The following example shows how you can toggle the item roll over hightlighting on a Flex ComboBox control’s dropdown menu by setting the useRollOver style using ActionScript or CSS.
Full code after the jump.
<?xml version="1.0" encoding="utf-8"?>
<!-- http://blog.flexexamples.com/2008/07/07/toggling-item-roll-over-highlighting-on-a-combobox-control-in-flex/ -->
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"
layout="vertical"
verticalAlign="top"
backgroundColor="white">
<mx:Script>
<![CDATA[
import mx.events.DropdownEvent;
private function comboBox_open(evt:DropdownEvent):void {
comboBox.dropdown.setStyle("useRollOver", checkBox.selected);
}
]]>
</mx:Script>
<mx:Array id="arr">
<mx:Object label="One" />
<mx:Object label="Two" />
<mx:Object label="Three" />
<mx:Object label="Four" />
<mx:Object label="Five" />
<mx:Object label="Six" />
<mx:Object label="Seven" />
<mx:Object label="Eight" />
<mx:Object label="Nine" />
<mx:Object label="Ten" />
</mx:Array>
<mx:ApplicationControlBar dock="true">
<mx:Form styleName="plain">
<mx:FormItem label="useRollOver:">
<mx:CheckBox id="checkBox" />
</mx:FormItem>
</mx:Form>
</mx:ApplicationControlBar>
<mx:ComboBox id="comboBox"
dataProvider="{arr}"
open="comboBox_open(event);" />
</mx:Application>
View source is enabled in the following example.
You can also set the useRollOver style in an external .CSS file or <mx:Style /> block, as seen in the following example:
<?xml version="1.0" encoding="utf-8"?>
<!-- http://blog.flexexamples.com/2008/07/07/toggling-item-roll-over-highlighting-on-a-combobox-control-in-flex/ -->
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"
layout="vertical"
verticalAlign="top"
backgroundColor="white">
<mx:Style>
ComboBox {
dropdownStyleName: myComboBoxDropdownStyles;
}
.myComboBoxDropdownStyles {
useRollOver: false;
}
</mx:Style>
<mx:Array id="arr">
<mx:Object label="One" />
<mx:Object label="Two" />
<mx:Object label="Three" />
<mx:Object label="Four" />
<mx:Object label="Five" />
<mx:Object label="Six" />
<mx:Object label="Seven" />
<mx:Object label="Eight" />
<mx:Object label="Nine" />
<mx:Object label="Ten" />
</mx:Array>
<mx:ComboBox id="comboBox"
dataProvider="{arr}" />
</mx:Application>
{ 4 comments… read them below or add one }
This is an interesting sample, though I must admit that usability is worse without the rollover, hence I could hardly think of any useful scenarios that would take advantage of this feature.
@Tangent
The rollover is off by default, so yes, the usability is reduced by default. Turning the rollover style ON is what’s important about this style setting.
I just found this site. I really like your samples. Can we use it in our web sites ?
An interesting example, try to benefit from it