Hello,
I am trying to pass a tag path to the points property on a sparkline, but I am unsuccessful in my approach. I have the points property bound to a custom value(HistoryTags) on the root container. Screenshots below showing tag bindings.
Any best practices or advice would be helpful!
Here is the error I get.You’re binding the path value to the value of the tag in that tag path (which is returning null) by using an indirect tag binding. A tag binding returns the value of the tag for the given tagpath. To pass the path itself, you need to use an expression binding to simply concatenate the tag path prefix with the suffix (/PV)
That's still a tag binding which is going and fetching the current value the the PV tag.
You want path to be the literal text of the tag path pointed to where the tag is. So instead of doing a tag binding of type expression, do an expression binding.
I’m most likely misunderstanding this, but my tag path is going to change with each new instance of an analog input. The tag path is being fed to my analog_Input_Popup, by an on click event from my analog_input template.
On-click event for referenceGetting a different error now.
So what I'd suggest is starting at your sparkline and working backwards. Right click copy the path for one of your tags/PV values and paste that into your custom.historytags without any binding. Start there and get your trend working. Once that's working then build the expression that takes the view.params.tagpath input and gives data in the same format that you need in the custom.historytags.
Also worth checking the documentation as it walks through an example pretty well:
Working backwards helped greatly. I was able to figure it out. I ended up using a combination of your recommendations and also @nminchin concatenate recommendation. Thanks for the help.
