Use read-only xf:input as xf:output in Orbeon? - orbeon

Question

Can i use a read-only xf:input act like xf:output in Orbeon?
How to set the value of a readonly input field?
simpler code sample:
<xf:input ref="//Some/Elements/TotalCredit"
value="round(($quantity) * ($creditPerUnit))">
</xf:input >
<xf:output ref="//Some/Elements/TotalCredit"
value="round(($quantity) * ($creditPerUnit))"/>
In the above code the xf:input shows only the initial value from the model!
It doesn't update!
But xf:output value is updated as expected!
So, how can set xf:input's value like xf:output?
I don't want to use calculation in bind.

Answer 1

In your example, you have an xf:input with both a ref and a value; I am not sure what you expect this to do, or if that makes sense, but for sure it currently won't work:
With the xf:output, you can have both a ref and a value, where the node pointed by ref can influence whether the xf:output is shown and the value gives it its value.
If you want to do the same with an xf:input, it can put the result of your calculation in the ref (in your case round(($quantity) * ($creditPerUnit))). If that expression returns an atomic value, then the input field will be readonly, which I think should take care of your situation.

Answer 2

This is how i made it, considering this and this posts.
//First Input
<xf:input ref="//Some/Elements/PreviousInputCreditPerUnit">
<xf:action ev:event="xforms-enabled xxforms-iteration-moved xforms-value-changed">
<xf:setvalue
ref="//Some/Elements/ReadOnlyInputIK"
value="round(($quantity) * ($creditPerUnit))"/>
</xf:action>
</xf:input>
//Second input
<xf:input ref="//Some/Elements/PreviousInputQuantity">
<xf:action ev:event="xforms-value-changed">
<xf:setvalue
ref="//Some/Elements/ReadOnlyInputIK"
value="round(($quantity) * ($creditPerUnit))"/>
</xf:action>
</xf:input>
//Third ReadOnly Input (acts like xf:output)
<xf:input ref="//Some/Elements/ReadOnlyInput">
</xf:input>
Note the action event in the first column of my repeated row:
ev:event="xforms-enabled xxforms-iteration-moved xforms-value-changed"
See this example from Orbeon.