Enum parameters don't work in scripts

[imagejan]

Consider the following Groovy script:

#@ org.scijava.ItemIO io

println io

(I also tested with other enum classes, e.g. net.imagej.ops.image.cooccurrenceMatrix.MatrixOrientation2D)

Running it results in an error message "A ItemIO is required but none exist."

Enum parameters should be rendered as dropdown choice widgets since aeccb57 (test added in 832c671), which seems to work in Java code, but not from scripts.

[imagejan]

The test added in 832c671 only tests the functionality of CommandInfo, but doesn't check for any matching widgets.

I was just quickly browsing through the source code, and it seems that while ObjectWidget should be suitable for Enums, we call model.getObjectPool() in SwingObjectWidget to test the available objects (and to create the JComboBox).

If my assumption is correct, we should be able to use ObjectWidget for enums if we adjust the behavior to first look for available choices (via getChoices()), and only if the list of choices is empty, fall back to querying the entire object pool. (This would at the same time enhance ObjectWidget to support a selection of choices even if more objects are available.)

Would that make sense, @ctrueden @hinerm ?

[imagejan]

For the record: it seems that @ctrueden started implementing this here (in 2017):

scijava/scijava-ui-swing@scijava:e68111f...scijava:8310e86

... but got stuck.