I’m new to Adobe scripting, and one of my first scripts deals with the activeDocument in Photoshop.
If there is no activeDocument, I want to display a message and terminate the script. My efforts
so far have been met with frustration. While developing the script in ExtendScript Toolkit,
I used the test expression "activeDocument in app", and everything worked as expected. And when I installed the script
in the Photoshop scripts folder and ran it from Photoshop with a document open, it also worked.
But when I ran the script from Photoshop with no document open, it failed.
Moreover, after that,the script failed when I tried to run it in ESTK.
I did some testing and found that my test expression, "activeDocument in app"
was returning true, even though no document was open.
Still in ESTK, I replaced the “app” with ”Application” in the test expression. That worked when
I stepped through the script. But when I tried to run it without stopping, it stopped at the
test expression, and displayed the error message, “Application is undefined.”
So how do I test for the presence of an open document in Photoshop ??
After posting this, I discovered the Photoshop Scripting Forum, and I found my answer there.—
I should have used “app.Documents.length” as my test expression.