DropDownList doesn't work in new window

In this code I'm creating a new window when I click the button. In the new window are TextInput and DropDownList components. When the new window opens, clicking the DropDownList does nothing - you have to click it a second time round to get it to open. However, click into the TextInput field first and then try opening the DropDownList works no problem.

Any reason why this is happening? Is this a bug or something I'm doing wrong? The issue occurs with Flex 4.1, AIR 2.5 SDK and Flex Hero (Sept 2010 release).

Below is the code or see attached FXP file:

// DropDownTest.mxml (application)
<?xml version="1.0" encoding="utf-8"?>
<s:WindowedApplication xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark"
xmlns:mx="library://ns.adobe.com/flex/mx"
width="400" height="300">
<fx:Script>
<![CDATA[
private function newWindow():void

{ this.close(); var w:MyWindow = new MyWindow(); w.open(); w.setFocus(); // **WORKAROUND** }

]]
>
</fx:Script>
<s:Button label="New Window" click="newWindow()"/>
</s:WindowedApplication>

// MyWindow.mxml (component)
<?xml version="1.0" encoding="utf-8"?>
<s:Window xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark"
xmlns:mx="library://ns.adobe.com/flex/mx"
width="400" height="300">
<s:TextInput/>
<s:DropDownList y="30"/>
</s:Window>

---

Thanks to Jason Szeto the workaround is to add "setFocus()" after the "open()" (see highlighted code above). In addition, custom components which feature drop downs which load into the new window need to call setFocus() on creationComplete.

Forum link: http://forums.adobe.com/message/3241460#3241460