Flex中如何利用rowCount属性，使List控件Resize时特定的行被显示

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1. <?xml version="1.0" encoding="utf-8"?>
2. <mx:Applicationxmlns:mx="http://www.adobe.com/2006/mxml"
3. layout="vertical"
4. verticalAlign="middle"
5. backgroundColor="white">
7. <mx:XMLid="mlbXML" >
8. <teams>
9. <leagueid="AL">
10. <teamlabel="Baltimore Orioles" />
11. <teamlabel="Boston Red Sox" />
12. <teamlabel="Chicago White Sox" />
13. <teamlabel="Cleveland Indians" />
14. <teamlabel="Detroit Tigers" />
15. <teamlabel="Kansas City Royals" />
16. <teamlabel="Los Angeles Angels of Anaheim" />
17. <teamlabel="Minnesota Twins" />
18. <teamlabel="New York Yankees" />
19. <teamlabel="Oakland Athletics" />
20. <teamlabel="Seattle Mariners" />
21. <teamlabel="Tampa Bay Devil Rays" />
22. <teamlabel="Texas Rangers" />
23. <teamlabel="Toronto Blue Jays" />
24. </league>
25. </teams>
26. </mx:XML>
28. <mx:XMLListCollectionid="alTeams"
29. source="{mlbXML.league.(@id == 'AL').team}"/>
31. <mx:ApplicationControlBardock="true">
32. <mx:Form>
33. <mx:FormItemlabel="rowCount:">
34. <mx:HSliderid="slider"
35. minimum="1"
36. maximum="10"
37. snapInterval="1"
38. liveDragging="true"
39. dataTipPrecision="0"
40. change="list.rowCount = event.value;"/>
41. </mx:FormItem>
42. </mx:Form>
43. </mx:ApplicationControlBar>
45. <mx:VBoxid="vBox" height="100%">
46. <mx:Listid="list"
47. maxHeight="{vBox.height}"
48. dataProvider="{alTeams}"
49. labelField="@label"/>
50. </mx:VBox>
52. </mx:Application>