flex tree自动显示横向滚动条实现代码

你是否在使用flex tree时遇到了横向滚动条无法自动显示的问题？别担心，狼蚁网站SEO优化将为你揭示具体的解决方案。这是一个关于如何让你的flex tree自动显示横向滚动条的技巧，或许你之前并未注意到。

代码如下：

```css

package .anydata.consumer.ponents {

import flash.events.Event;

import mx.controls.Tree;

import mx.core.ScrollPolicy;

import mx.core.mx_internal;

/ 自动显示横向滚动条 /

public class AutoSizeTree extends Tree {

public function AutoSizeTree() {

super();

horizontalScrollPolicy = ScrollPolicy.AUTO; // 设置横向滚动策略为自动

}

override public function get maxHorizontalScrollPosition():Number {

if (isNaN(mx_internal::_maxHorizontalScrollPosition)) return 0;

return mx_internal::_maxHorizontalScrollPosition;

}

override public function set maxHorizontalScrollPosition(value:Number):void {

mx_internal::_maxHorizontalScrollPosition = value;

dispatchEvent(new Event("maxHorizontalScrollPositionChanged"));

scrollAreaChanged = true;

invalidateDisplayList();

}

override protected function updateDisplayList(unscaledWidth:Number, unscaledHeight:Number):void {

var diffWidth:Number = measureWidthOfItems(0, 0) - (unscaledWidth - viewMetrics.left - viewMetrics.right);

var indentation:Number = getStyle("indentation");

if (diffWidth <= 0) maxHorizontalScrollPosition = NaN;

else maxHorizontalScrollPosition = diffWidth + indentation;

super.updateDisplayList(unscaledWidth, unscaledHeight);

}

}

}

```

希望这个技巧能够帮助你解决问题。如果你对狼蚁网站的SEO优化或其他技术话题感兴趣，欢迎与我们分享交流。记住，不要错过任何一次学习的机会！