如何在Flex 3的列表控件上动态设置selectedIndices？

Question

How to set selectedIndices dynamically on list control on flex 3?

I am using list within repeater control. I have an option multiple selection for list . when i am selecting the multiple options i can get selected indices as array and stored in database. At the same time while list out those selected values in an list control on selected indices property it will not set correctly. Here i have given my code.

    <mx:VBox y="30" x="1" id="vboxState">
        <mx:Repeater id="rptrRadioState" dataProvider="{rptrArr}">
            <mx:HBox>
                <mx:List id="cmbstateradio" selectedIndices="{new Array(1,3)}" dataProvider="{listarr}" allowMultipleSelection="true" change="(event.currentTarget.getRepeaterItem().selectedval = cmbstateradio[event.target.repeaterIndices].selectedIndices)"/>
            </mx:HBox>
        </mx:Repeater>
    </mx:VBox>

It is works fine. But if i would try in below mentioned way it was not work.

    [Bindable]
            public var arr:Array = new Array(1,3);

            [Bindable]
            public var rptrArr:ArrayCollection = new ArrayCollection([{label:"TestA",data:0,selectedval:new Array(1,3)},{label:"TestB",data:1,selectedval:arr},{label:"TestC",data:2,selectedval:arr}]);

    <mx:VBox y="30" x="1" id="vboxState">
        <mx:Repeater id="rptrRadioState" dataProvider="{rptrArr}">
            <mx:HBox>
                <mx:List id="cmbstateradio" selectedIndices="{new Array(rptrRadioState.currentItem.selectedval)}" dataProvider="{listarr}" allowMultipleSelection="true" change="(event.currentTarget.getRepeaterItem().selectedval = cmbstateradio[event.target.repeaterIndices].selectedIndices)"/>
            </mx:HBox>
        </mx:Repeater>
    </mx:VBox>        

Answer 1

Problem may be in this part of code:

"{new Array(rptrRadioState.currentItem.selectedval)}"

As I see you create array of array. Try to remove new Array() from statement. Then it will be look next:

"{rptrRadioState.currentItem.selectedval}"

Also, you need to use different arrays for selectedIndices . For example:

[Bindable]
public var rptrArr:ArrayCollection = new ArrayCollection([
                                                              {label: "TestA", data: 0, selectedval: [1, 3]},
                                                              {label: "TestB", data: 1, selectedval: [1, 3]},
                                                              {label: "TestC", data: 2, selectedval: [1, 3]}
                                                         ]);

PS Unfortunately, I cannot explain why it doesn't work with one instance of array for all lists' selectedIndices . Maybe someone else know the answer of this.

Answer 2

You are using same array arr in different elements. If you really need this behavior it's better trying to clone the array arr instead of assign it to many components. Try not using same array arr I think this is the problem. Some elements on flex 3 must not be shared in different visual components. I prefer to assign properties on repeated components in repeat event instead of doing it online.