Question

Use calculated attribute in an XPath constraint

1

I get the error message that I can't use attributes which are being calculated by a microflow. Is there a workaround for this? I need this value in another microflow, where I want to retrieve a list in which all objects occur where this attribute is true.

asked 2013-05-28

Robin Trietsch

1 answers

Rom van Arendonk · Accepted Answer · 2013-05-28

Work arounds:

Change your XPath constraint to include the conditions when your calculated value would become true
Actually store the value in the database, instead of calculating it. You would have to implement logic on save buttons where relevant attributes change and update this attribute as well
Retrieve all object and manually loop over them to construct the list (or perhaps Mendix allows you to use the Filter List action).

You should be careful with virtual attributes: apart from this issue, they are fairly inefficient, see e.g. this blog post