Flex Gumbo中如何通过trackingLeft和trackingRight样式，调整TextBox内容左右间距

1. <?xml version="1.0" encoding="utf-8"?>
2. <Applicationname="TextBox_trackingLeft_test"
3. xmlns="http://ns.adobe.com/mxml/2009"
4. layout="vertical"
5. verticalAlign="middle"
6. backgroundColor="white">
8. <ApplicationControlBardock="true">
9. <FormstyleName="plain">
10. <FormItemlabel="trackingLeft:">
11. <HSliderid="slider1"
12. minimum="0"
13. maximum="20"
14. value="0"
15. snapInterval="1"
16. tickInterval="1"
17. liveDragging="true"/>
18. </FormItem>
19. <FormItemlabel="trackingRight:">
20. <HSliderid="slider2"
21. minimum="0"
22. maximum="20"
23. value="0"
24. snapInterval="1"
25. tickInterval="1"
26. liveDragging="true"/>
27. </FormItem>
28. </Form>
29. </ApplicationControlBar>
31. <BoxbackgroundColor="haloSilver" backgroundAlpha="0.4">
32. <Graphic>
33. <TextBoxid="textBox"
34. text="The quick brown fox jumps over the lazy dog."
35. trackingLeft="{slider1.value}"
36. trackingRight="{slider2.value}"
37. textAlign="justify"
38. textJustify="interWord"
39. fontSize="16"
40. width="400"/>
41. </Graphic>
42. </Box>
44. </Application>