[PATCH] Disable the JosmAction Orthogonalize.Undo when nothing is selected

[floscher]

Currently (version 11088) a NullPointerException occurs, when you have no OsmDataLayer open and press Shift+Q.

The reason for that is, that the JosmAction Orthogonalize.Undo is always active, but its actionPerformed(e) method assumes, there is always an edit layer. If there is none, it throws a NullPointerException.

This patch fixes this behaviour by letting this action implement the methods updateEnabledState() and updateEnabledState(Collection<? extends OsmPrimitive> selection). So now the action is only active, when an edit layer exists and at minimum one OsmPrimitive is selected.

[simon04]

The disadvantage of disabling the Undo action on an empty selection is that the usage notification "Please select nodes that were moved by the previous Orthogonalize Shape action!" is not being shown.

[floscher]

I tried to align the action with the behaviour of other actions. E.g. the OrthogonalizeAction, AlignInCircleAction, AlignInLineAction, DistributeAction and many more also don't show a notification when nothing is selected.

I think for these actions it is clear to the user that nothing happens, if nothing is selected.

[floscher]

To clarify: The above-mentioned notification would still be shown in cases where OsmPrimitives are selected, which have not been orthogonalized before.
The only case where it was shown previously, but won't be shown after this patch, would be when an OsmDataLayer exists, but contains no selected OsmPrimitives.

[simon04]

In 11116/josm:

fix #13766 - Disable the JosmAction Orthogonalize.Undo when nothing is selected (patch by floscher)

[simon04]

Thank you!