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how to make an element undeletable [message #538534]

Mon, 07 June 2010 17:38

Eclipse User

For some reasons I want to make one element non deletable once created,
Is there a way to do that ?

Re: how to make an element undeletable [message #538545 is a reply to message #538534]

Mon, 07 June 2010 18:17

Eclipse User

Hi,

you can try to override the getDestroyElementCommand() method of the
ItemSemanticEditPolicy of the corresponding node edit parts.

protected Command getDestroyElementCommand(DestroyElementRequest req) {
return UnexecutableCommand.INSTANCE;
}

For links use getDestroyReferenceCommand() accordingly. Note that this
includes that the parent edit part can not be deleted, too.

Maybe you need to additionally install another policy to prevent deletion by
the del key also:
installEditPolicy(EditPolicy.COMPONENT_ROLE, new ComponentEditPolicy() {
protected Command getDeleteCommand(GroupRequest request) {
return null;
}
});

HTH
Axel

bachra04 wrote:

> For some reasons I want to make one element non deletable once created,
> Is there a way to do that ?

Re: how to make an element undeletable [message #538856 is a reply to message #538545]

Tue, 08 June 2010 15:44

Eclipse User

I tried but I had the following compile error:

Type mismatch: cannot convert from UnexecutableCommand to Command
even casting does not work.

Any idea ?

Re: how to make an element undeletable [message #539109 is a reply to message #538534]

Wed, 09 June 2010 12:04

Eclipse User

be careful with command: some are emf, other gef or gmf. So check carefully the right type of the UnexecutableCommand

Re: how to make an element undeletable [message #539162 is a reply to message #538534]

Wed, 09 June 2010 15:40

Eclipse User

Thanks Aurelien,
I tried it and works perfectly.

Re: how to make an element undeletable [message #539450 is a reply to message #539162]

Thu, 10 June 2010 14:32

Eclipse User

I have one problem when deleting using the key:
THE element itself is not deleted but its children were deleted.