[josm-dev] MapMode, GeoImageLayer, mouseAdapter, Flags, Undo

[Holger Mappt]

Hi,

I have a proof of concept for my ticket 7712.  Until now I changed the 
GeoImageLayer directly to keeps things simple.  Now I want to move the 
additional code into a plug-in.  That raises a few questions.

The GeoImageLayer uses a MouseAdapter that is added and removed by a 
MapModeChangeListener.  But what exactly is a MapMode?  I can click on a 
photo whenever it is displayed.  How is that related to the MapMode?

I want to be able to move photos of the active GeoImageLayer.  Can I use 
a LayerChangeListener to register my MouseMotionAdapter or do I need a 
MapModeChangeListener too?  Right now I do the same what the 
GeoImageLayer does, i.e. use the MapModeChangeListener.

What is the best way to add a MouseMotionAdapter to the active 
GeoImageLayer from a plug-in?  Do I just implement the right 
ChangeListener and use it to add/remove the MouseMotionAdapter?  Or 
would I register the MouseMotionAdapter in the GeoImageLayer?  Or 
something else?  What plug-in would be a good example?

I want to mark an image as moved to be able to save the new coordinates 
afterwards.  What is the recommended way to implement such a flag?  Is 
there a type for flags, how do I name the set/get methods?

The undo/redo seems to work with OSM data only.  Is there a way to have 
a separate undo buffer for the GeoImageLayer?  How would it work?

Thanks,
Holger