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Create general handler for creating/deleting parts [message #1802903]

Mon, 18 February 2019 18:42

João Pedro

Messages: 52
Registered: December 2014

Member

I'm wondering how to make a global Handler (not an IOnClickHandler !! ).

And why do I need a handler extending AbstractHandler for this? When 3 events happen I need to create/delete some parts and as far as I can see the init() and commit() functions are part of the AbstractHandler.

Am I looking at this in the wrong way and do I need an operation instead of a handler? Any feedback is deeply appreciated

[Updated on: Mon, 18 February 2019 18:42]

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Re: Create general handler for creating/deleting parts [message #1802908 is a reply to message #1802903]

Mon, 18 February 2019 19:48

Matthias Wienand

Messages: 230
Registered: March 2015

Senior Member

Hi Joao,

a handler may implement any number of interfaces. Hence, you can react to all gestures using just a single handler. Note that an open transaction is only closed when all active gestures are finished, though.

Furthermore, a handler implementation does not need to extend AbstractHandler. That is just convenience (e.g. init(), commit() methods that you already use).

Each policy provides init() and commit() methods that can be used to initialise and commit a policy, respectively. This can also be seen from the AbstractHandler implementation.

Best regards,
Matthias

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Re: Create general handler for creating/deleting parts [message #1802988 is a reply to message #1802908]

Wed, 20 February 2019 10:22

João Pedro

Messages: 52
Registered: December 2014

Member

Ok understood!

Just one question though. If I do creationPolict.init() and creationPolicy.commit() instead of init(creationPolicy) and commit(creationPolicy) (methods inherited from AbstractHandler) I can't undo the newly create operation. Can you explain why and how to I work around this?

Thanls

[Updated on: Wed, 20 February 2019 10:22]

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Re: Create general handler for creating/deleting parts [message #1802989 is a reply to message #1802988]

Wed, 20 February 2019 10:44

João Pedro

Messages: 52
Registered: December 2014

Member

I can answer my own doubt :P

Looking at the AbstractHandler.commit and init I found out that I was missing some stuff in order to create an ITransactionalOperation.

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