Dropdown List Not Displaying Data

I have a display with 31 dropdown list on it. This is used to modify a recipe. The display is acting strange though. Every now and then I will make a change on one of the dropdowns and the change will read correctly in the PLC but the text on this dropdown then changes to the text as if I have 0 value but the value reads correctly. Other times when I load a recipe a few of the dropdowns will display nothing at all. There is data in the PLC say value 38 which should read “Fill Tanks” but the dropdown will just be blank. Anyone have an idea as to why this is acting this way?

I assume that the values that show blank are actually in the drop down’s dataset?

How are you binding the value to the dropdown?

Try turning off search on the dropdown and see if that corrects the issue. That functionality can make text appear off screen for some reason.

1 Like

The drop down has 100 custom properties. These custom properties are linked to step descriptions inside the PLC. I have the Data bound to the custom properties with an update cell function to fill out the data set with the custom properties. All properties have text in them non are left blank. Selected Value is bound the the PLC tag that holds the value. Nothing else on the dropdown has a binding.

That’s a lot of work! to create all of those custom properties, all of the bindings on them, and all of the bindings on the cell updates. I don’t know if it’s the cause of your issue, but I can’t imagine its helping.

How often are these descriptions changing? If it was me, I would read in all of your tag values with a script in one read call and create the dataset in the script in a few lines of code. I would even consider reading the values using system.opc.read instead of having to create tags in the tag browser. Call the script when the mouse is clicked (or hovered over the component - I can’t remember if on clicked works well or not for a dropdown component).

1 Like