changin下拉列表的默認寬度和高度

Question

我想要一個足夠寬的下拉列表，以便在主控件的顯示區域的下拉列表中容納更大的項目。（。也就是MX Combobox功能的下拉列表） 請指導我在這。

Answer 1

您應該創建自定義的DropDownList（延長原），並覆蓋dataProvider setter和measure()方法。在dataProvider setter中，您應該調用invalidateSize()，並且應該重複您的數據提供程序並查找最大標籤（您可以將新文本分配給標籤並比較它們的寬度）。

Answer 2

從Flex示例檢出this example。您只需爲DropDownList創建一個外觀並設置popUpWidthMatchesAnchorWidth="false"屬性。

Answer 3

這將調整下拉寬度到數據寬度。 我忘記了哪裏的例子是我從哪裏得到的代碼。我相信rowCount可以設置高度。

package valueObjects.comboBox{ 

    import flash.events.Event; 
    import mx.controls.ComboBox; 
    import mx.core.ClassFactory; 
    import mx.core.IFactory; 
    import mx.events.FlexEvent; 

    public class ExtendedComboBox extends ComboBox{ 
     private var _ddFactory:IFactory = new ClassFactory(ExtendedList); 

     public function ExtendedComboBox(){  
      super(); 
     } 
     override public function get dropdownFactory():IFactory{ 
      return _ddFactory; 
     } 
     override public function set dropdownFactory(factory:IFactory):void{ 
      _ddFactory = factory; 
     } 
     public function adjustDropDownWidth(event:Event=null):void{  

     this.removeEventListener(FlexEvent.VALUE_COMMIT,adjustDropDownWidth); 
      if (this.dropdown == null){ 
       callLater(adjustDropDownWidth); 
      }else{ 
       var ddWidth:int = this.dropdown.measureWidthOfItems(-1,this.dataProvider.length); 
       if (this.dropdown.maxVerticalScrollPosition > 0){      
        ddWidth += ExtendedList(dropdown).getScrollbarWidth();      
       }     
       this.dropdownWidth = Math.max(ddWidth,this.width);     
      } 
     } 
     override protected function collectionChangeHandler(event:Event):void{ 
      super.collectionChangeHandler(event); 
      this.addEventListener(FlexEvent.VALUE_COMMIT,adjustDropDownWidth);   
     } 
    } 
} 



package valueObjects.comboBox{ 
    import mx.controls.List; 

    public class ExtendedList extends List{ 
     public function ExtendedList(){ 
      super(); 
     } 
     public function getScrollbarWidth():int{ 
      var scrollbarWidth:int = 0; 
      if (this.verticalScrollBar != null){ 
       scrollbarWidth = this.verticalScrollBar.width; 
      } 
      return scrollbarWidth; 
     } 

    } 
} 




<?xml version="1.0" encoding="utf-8"?> 
<mx:Canvas xmlns:mx="http://www.adobe.com/2006/mxml" mlns:comboBox="valueObjects.comboBox.*" > 

    <comboBox:ExtendedComboBox labelField="data.totext()" itemRenderer="mx.controls.Label" /> 
</mx:Canvas> 

Answer 4

它是通過下面的代碼來實現的：

public override function set dataProvider(value:IList):void 
    { 

     var length:Number = 0; 
     var array:Array = value.toArray(); 
     super.dataProvider = value; 
     var labelName:String = this.labelField; 
     var typicalObject:Object =new Object(); 
     for each(var obj:Object in array) 
     { 
      var temp:Number = obj[labelName] .length; 
      if(length < temp) 
      { 

       length = temp; 
       Alert.show(" length "+length.toString()); 
       typicalObject = obj; 
      } 
      //length = length < Number(obj[labelName].length) ? Number(obj[labelName].length) : length 
      //Alert.show(obj[labelName].length); 
      this.typicalItem = typicalObject; 
     } 



    } 

Answer 5

對不起，更好起飛從字段的寬度和高度二者。

Answer 6

要增加組合框下拉列表的高度，請使用「rowCount」屬性。這是用於Flex 3.6.0