Flex:如何将S:列表中的Sqlist查询绑定到S:Textarea

Question

在flex builder 4.6中,我试图从am sql查询绑定数据,在一个<s:List>项目渲染器中显示<s:Textarea>

我的守则如下:

<s:List id="listapagar" x="304" y="276" width="330" height="42" borderVisible="false"
        color="#FF0000" dataProvider="{dataProvider}" enabled="false" fontSize="22"
        fontStyle="italic" fontWeight="bold" labelField="nome" textAlign="center"
        textDecoration="underline">
    <s:itemRenderer>
        <fx:Component>
            <s:ItemRenderer>
            <s:TextArea id="apagar" width="330" height="42" text="R$ {data.valorapagar}" />      
            </s:ItemRenderer>
        </fx:Component>
    </s:itemRenderer>
</s:List>

---

在这里,我的sql显示通过<s:list>:

protected function buttonX():void
        {
            var sqlConnection:SQLConnection = new SQLConnection();
            sqlConnection.open(File.applicationDirectory.resolvePath("testeDb.sqlite"));

            var stmt:SQLStatement = new SQLStatement();
            stmt.sqlConnection = sqlConnection;
            stmt.text = "SELECT * FROM comandatual order by numerodatransacao desc limit 1 ";
            stmt.execute();

            dataProvider = new ArrayCollection(stmt.getResult().data);
        }

---

在它之后,我试图将结果显示在s:TextArea id ="apagar"并与另一个文本区域绑定,以执行简单的减去calc,如下所示:

---

<fx:Binding source="apagar.text" destination="restroco.text"/>

---

<fx:Model id="Calculos" >

        <Calculos>
            <!-- Perform a calculation. -->
            <a>{(Number(restroco.text)) - 3}</a>
            </Calculos>
    </fx:Model>

---

但此时,flex返回一个不能让我前进的错误:

1120:访问未定义的属性apagar.弹性问题

---

所以,我被困,如果有人想看到我的完整代码,他们在这里:

http://freetexthost.com/srxslotf1x

Answer 1

正如@RIAStar 所解释的，您fx:Model无法访问apagar. 除了建议的解决方案之外，您还可以使用IndexChangeEvent：

<fx:Script>
    <![CDATA[
        import spark.events.IndexChangeEvent;

        private var apagarNum:Number = NaN;

        protected function selectionChangedHandler(event:IndexChangeEvent):void
        {
            apagarNum = Number(listapagar.selectedItem.valorapagar);
        }

    ]]>
</fx:Script>

<fx:Model id="Calculos" >
    <Calculos>
        <!-- Perform a calculation. -->
        <c>{(Number(restroco.text)) - 3}</c>
        <!-- calcular com valor a pagar -->
        <d>{apagarNum - 3}</d>
    </Calculos>
</fx:Model>

<s:List id="listapagar" change="selectionChangedHandler(event)" ...>