I dont think this is possible as DataBinding expressions are not supported with attributes processed at run time. Since here Model is processed at the compile time itself and the variable can be accessed only at run time. Since your model expects a path at compile time only it cannot be assigned to a dynamic variable.
I want to get access to xml & i have xmlpath
How can I do it?
You need to directly assign the path instead of assigning it through a variable.
<mx:Model id="dataSet" source="assets/data.xml"/>