Dictionary declaration in MXML, is it possible?

Question

In MXML it's possible to declare object instances, even for dynamic objects, like so:

<mx:Object>
    <mx:foo>bar</mx:foo>
    <mx:bar>foo</mx:bar>
</mx:Object>

Is it possible to do the same with the Dictionary class without using some MXML wrapper class?

Answer 1

No, I don't think Dictionary is bound to MXML.

Do you really need a Dictionary for what you want to accomplish?

Answer 2

I'm not completely sure I understand the question, but if you're asking whether you can declare a dictionary in MXML, yes, you can; here's some code demonstrating a Dictionary declared in MXML, along with a form showing how you might add items to the dictionary dynamically:

<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="vertical" xmlns:utils="flash.utils.*" creationComplete="onCreationComplete()">

    <mx:Script>
     <![CDATA[

      private function onCreationComplete():void
      {
       showContents();
      }

      private function onBtnClick():void
      {
       addProperty();
       showContents();
      } 

      private function showContents():void
      {
       txt.text = "";

       for (var k in d) 
        txt.text += k + ": " + d[k] + "\n"
      }

      private function addProperty():void
      {
       d[pname.text] = pvalue.text;

       pname.text = ""; 
       pvalue.text = "";

       pname.setFocus();
      }

     ]]>
    </mx:Script>

    <mx:VBox>
     <mx:Label text="Dictionary Contents" />
     <mx:TextArea id="txt" width="350" height="200" />
     <mx:HBox>
      <mx:VBox>
       <mx:Label text="New Property Name" />
       <mx:TextInput id="pname" text="pets" />
      </mx:VBox>
      <mx:VBox>
       <mx:Label text="New Property Value" />
       <mx:TextInput id="pvalue" text="dog, cat, fish" />
      </mx:VBox>
     </mx:HBox>
     <mx:Button id="btn" label="Add" click="onBtnClick()" />
    </mx:VBox>

    <utils:Dictionary id="d">
     <utils:fname>Chris</utils:fname>
     <utils:lname>Nunciato</utils:lname>
    </utils:Dictionary>

</mx:Application>

Hope that helps! If I've totally missed the point, post back and I'll see if I can help out.

Answer 3

It is possible, if you import the right namespace

    <mx:Application ... xmlns:utils="flash.utils.*">
        <utils:Dictionary>
            <utils:foo>bar</utils:foo>
            ...
        </utils:Dictionary>
        ...

But I see no good reason to do this. The advantage of a Dictionary over a plain Object (or <mx:Model>), what you would normally use, is that you can use objects other than String as key. But you can't write a non-String key in MXML.

In other words: yes you can create one, but there's no point.