Dropdown Default Value

General Discussion
21

I would spend some time on how read blocking works. For now, run your script in the script console for testing purposes. Pay attention in how the results are a list of qualified values.

https://docs.inductiveautomation.com/display/DOC81/system.tag.readBlocking

You mentioned being new. I highly recommend you spend time going through inductive university.

22

2 issues:

  1. As @jlandwerlen alluded to, you have a misunderstanding in what readBlocking returns. This returns a list of QualifiedValue objects, even if you only supply a single tagpath.
    Also, consider using the format function for your string substitutions/concats.
    E.g.
OPC_Hopper_Tag = "[default]Modbus_Master_PLC/GVL_OPC_Hopper_{}_Match'.format(self.view.getChild('root').custom.HopperID) # no need to convert the arg to str
OPC_Hopper_Tag_Value = system.tag.readBlocking(OPC_Hopper_Tag)[0].value # get the first item and get the QualifiedValue's `value` property, which is the value of the tag.
  1. Don't use scripting for something that can be natively handled by bidirectional indirect tag bindings, such as this.
    You don't need the scripting at all in this instance. Just bi-directionally bind your dropdown props.value properties
23

nmichin
Thank you that worked nicely,

24

I hope you mean No. 2 worked nicely!

25

Hi Mate

I did the Script first to see if that worked and it did, but changed it to the Bidirectional Binding and it works as well,

This is the first project i was doing with Ignition as the previous company that was looking after my customer when broke so i got stuck with the task lol, we all had to start some where i just happen to start on an existing system and get a customer out of a pickle.

Thanks again for the assistance much appreciated.

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