Bug #4409


View Documentation for an actor works once

Added by Oliver Soong about 14 years ago. Updated about 14 years ago.

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I can view the documentation for an actor in the actor library once. After that, I can no longer drag actors onto the canvas and I can no longer view any more documentation.

I just updated and this is observed on linux and XP.

Restarting Kepler seems to at least reset this.

Actions #1

Updated by Oliver Soong about 14 years ago

When trying to view documentation the second time, there is some error information on the console:

Error in getting actor in ShowDocumentationAction
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at ptolemy.vergil.basic.GetDocumentationAction.showDocumentation(

If I try to drag an actor on the canvas after that, I get an error dialog:

Change failed
Cannot create entity without a class name. in [external stream] at line 2 and column 25

There are additional console errors:

Error inside GetMomlFromLSID.getMoml(): empty error message
Error creating alternateGetMoml!
Change failed: <group><group name="auto">
<entity name="SelectionDialog">
<property name="_location" class="ptolemy.kernel.util.Location" value="{155, 245}"/>
Change made by: ptolemy.vergil.basic.EditorDropTarget$DTListener@6faf61
Exception: Cannot create entity without a class name. in [external stream] at line 2 and column 25

Actions #2

Updated by Oliver Soong about 14 years ago

I should clarify and add a workaround. This seems to occur only when right-clicking in the components tree and viewing documentation. The workaround is to drag the actor onto the canvas and view documentation by right-clicking on the actor, not in the components tree.

Actions #3

Updated by ben leinfelder about 14 years ago

Still happening for me in WRP suite...retargeting to 2.0 - it seems like a bad idea to release with a bug happening for people when they are seeking help and guidance.

It seems like the object in the component tree is being modified when viewing documentation - that would seem like an unnecessary thing to do?

Actions #4

Updated by Aaron Aaron about 14 years ago

Should be OK now.

Actions #5

Updated by Redmine Admin over 10 years ago

Original Bugzilla ID was 4409


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