Best Practice for Passing Values Between Scripting Events

Ignition
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My experience with programming has taught me that global variables are a thing to be avoided. Looking to see if this holds true for Ignition as well and what other options are available.

I have a particular set of library scripts where I am using some global variables. A "mousePressed" event gets the client height and width and stores them in globals. Then a "mouseDragged" event, I pull these globals and use them to prevent a user from dragging a popup into no-man's-land. I want to use this script set wherever I have a popup, so I prefer it in the library for ease of use and maintainability.

Anywho, I see a number of issues with this from an extensibility and multiclient access point of view when using global variables.

So getting to my question, is there a clean way to send data between scripting events without using global scripting variables?

I would be more comfortable with client tags, but it looks like scripts in the project library cannot address client tags.

Running Ignition 8.0 for this project.

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In Vision, script module global variables, in client scope, are local to the client instance. So are not typically a problem for user clashes.

In Perspective, not so much.

You need state stored somewhere, and script globals can hold state. If you need it to be component or window-specific, look at .putClientProperty and friends.

Not true at all. But since Vision client tags only exist in a client instance, only calls into a project library script from client scope will be able to access them. (Project library scripts have no scope of their own--their scope is the scope of whatever calls them.)

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Beautiful answer, thank you.