Question

我在.mxml文件中的布局是这样的： -

<?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="600" height="800" >
        <fx:Declarations>
            <!-- Place non-visual elements (e.g., services, value objects) here -->
        </fx:Declarations>
        <mx:HBox width="100%" horizontalAlign="right" top="20">
            <mx:ComboBox id="comboBox" fontSize="12" width="10%" dataProvider="{middleStack}"  name="versioncombo"/>
        </mx:HBox>
        <mx:VBox top="50" left="10" >
            <mx:Label text="Builds" fontSize="18">
            </mx:Label>
            </mx:VBox>
        <mx:VBox top="50" horizontalAlign="center" left="200">
            <mx:Label text="Date" fontSize="18">
            </mx:Label>
        </mx:VBox>
        <mx:VBox top="50" horizontalAlign="center" right="10">
            <mx:Label text="Release" fontSize="18">
            </mx:Label>
        </mx:VBox>
        <mx:VBox height="100%" width="100%" styleName="centerLightGreyBg" verticalGap="0">

            <mx:ViewStack id="middleStack" width="100%" height="100%" backgroundAlpha="0" change="changev()">
            </mx:ViewStack>

        </mx:VBox>
        <fx:Style>

现在，我想通过读取XML文件中的值，将值添加到id = combobox和name = versioncombo的组合框中。我的xml是这样的。

<Install>
  <version>
    <number>5.0</number>
    <build>907681</build>
    <path></path>

  </version>
  <version>
    <number>6.2</number>
    <build>1043305</build>
    <path></path>

  </version>
</Install>

我想用版本号填充组合框，即5.0,6.2。

我尝试按照此链接但无法执行此操作 http://www.parorrey.com/blog/flash-development/as3-adding-dropdown-combobox-flash-component-using-actionscript-with-xml-data/

AS3 Procedural. Randomise order of Items in Combobox From XMl

我是AIR的新手。

我试过这样： -

import fl.data.DataProvider; 

            var country:String='';
            var countriesList:Array = [];

            //URLLoader class helps you to load data from an external source such as a URL

            var xmlLoader:URLLoader ; 
            var xmlData:XML = new XML(); 

            public function Pathfinding() {
                // constructor code
                xmlLoader = new URLLoader();
                xmlLoader.addEventListener(Event.COMPLETE, LoadXML);
                xmlLoader.load(new URLRequest("grid.xml"));
            }

            function LoadXML(e:Event):void { 
                xmlData = new XML(e.target.data); 
                xmlData.ignoreWhite = true;

                ParseCountries(xmlData); 
                //trace(xmlData);
            } 

            function ParseCountries(countriesInput:XML):void { 

                var countriesListing:XMLList = countriesInput.country.attributes(); 
                var i:int;  

                for each (var countryName:XML in countriesListing) { 

                    //populate the countriesList array to be used with ComboBox
                    countriesList.push( {label:countryName, data:countryName} );
                    trace(countryName);

                }

                versioncombo.prompt = "Select version:"; 
                versioncombo.dataProvider = new DataProvider(countriesList); 
                versioncombo.addEventListener(Event.CHANGE, dropDownHandler);
                versioncombo.dropdown.rowHeight  = 30;
                versioncombo.width = 150;

            } 


            function dropDownHandler(event:Event):void { 

                country = ComboBox(event.target).selectedItem.data;     
                trace("selected country: "+ country);
                //do something here whatever you want 
            }   
comboBox.prompt = "Select Country:"; 
            comboBox.dataProvider = new DataProvider(countriesList); 
            comboBox.addEventListener(Event.CHANGE, dropDownHandler);
            comboBox.dropdown.rowHeight  = 30;
            comboBox.width = 150;

但是收到错误＆＃34; -1180：调用可能未定义的方法DataProvider。＆＃34;

                comboBox.dataProvider = new DataProvider(countriesList);

不适合我。

Answer 1

您将name属性与您定义的id组件的ComboBox属性混淆。您需要使用id来引用ComboBox实例。

来自Working with Components：

您应该为每个动态创建的实例变量声明一个实例变量组件并存储对其中新创建的组件的引用，正如MXML编译器在为a设置id属性时所做的那样组件实例标签。然后，您可以访问动态创建的组件的方式与MXML中声明性创建的组件相同。

Answer 2

您需要read about正确使用dataprovider。您不需要创建新实例，例如“new DataProvider”。请使用 ArrayCollection 或任何 IList

从actionscript 3中的xml文件读取值到组合框中

2 个答案: