Hi all, There must be a simple solution to this, but it's Friday afternoon and my brain isn't cooperating. I am creating a simple terminal by means of which a user can interact with an instrument. My question concerns the Query String control only. The Send button and the Terminal Table are there for reference. Here is my desired behavior: a) The user types a command into the Query field and types Enter or Return. An Event fires and the query is sent to the instrument. The focus remains on the Query field.b) With no other UI actions, the user types Enter or Return again and again, firing an Event that sends the query to the instrument each time Enter or Return are typed. The focus remains on the Query field. Here's what I've got: This achieves a), but fails at b). The reason is, since the value of the Query field has not changed, the Value Change event does not fire when the user starts spamming the Enter or Return keys. There is a way around this, as suggested by this post. Here's the solution in a nutshell: Instead of looking for Value Change of the Query control, the event fires on every Key Down event of the control, and looks for an Enter or Return keypress. This catches the user action even if the contents of the Query field have not changed. The problem with this approach is that when this event fires, I need to read the value of the Query String control and send it to the instrument, but the value I obtain via the Query Local Variable is the old value, presumably because the Key Down event fires before the value of Query is registered as changed. Is there a way to programatically "enter" the contents of the String control so it is registered as a Value Change, before I query it via a Local Variable? Is there a different way I should be going about this? I'd rather not do anything that tied the Enter or Return keys to this particular field, since I have plenty of other UI elements that need these keys in my program. Alternatively, is there a way to make the Query String control "Value Change" event fire when the user hits Enter or Return even if the value has not changed? Thank you for your input!

I figured it out. 1) The String control (Query) is set to Update Value while Typing. 2) Register the Key Down event for the String control. If Enter or Return were pressed, send the state machine to the "Send Query" state. 3) In the "Send Query" state read the value of the String control via Local Variable. This has the desired behavior of allowing the user to hit Enter or Return over and over to repeatedly send a command, and the user can also type in a new command and send it by hitting Enter or Return. Thank you to all who helped me think this through!

LabVIEW

Using a String control with Enter, Return and allowing for repeated identical input

Solved!

Yeah I definitely agree. My usual plan is to just have a class icon, which is text on a colored background at the top, and just write a text description in the three or so lines there are. Fast, descriptive, visually pleasing, and using the text options means there's no fiddling with the pencil tool when you want to change something.

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LabVIEW

Using a String control with Enter, Return *and* allowing for repeated identical input

Re: Using a String control with Enter, Return *and* allowing for repeated identical input

Using a String control with Enter, Return and allowing for repeated identical input

Re: Using a String control with Enter, Return and allowing for repeated identical input