Predicates:¶

new(?Ref, +Term)

Create an XPCE object from Term and bind the object to the reference Ref. The functor-name of Term describes the class from which to create an instance. The arguments of Term are used as initialisation arguments for the new object. If the object was created successfully and Ref is a variable, Ref will be unified with the term @<RefNumber>. If Ref is a term of the form @<Atom>, this term will serve as a reference for the new object.

For example ?- new(@p, picture('Hello World'). Creates a graphical window object with title "Hello World".

send(+Ref, +Selector, +Args...)

Ref is a reference to an existing XPCE object. Selector is the name of a (send-)method defined on (the class of) this object and Args are terms that describe arguments to be passed to the method.

send/[2-12] will convert the arguments to XPCE data objects, resolve the procedure (C-function, Prolog predicate) implementing the method and run the implementation. If the execution is successful, send succeeds, otherwise send fails.

For example ?- send(@p, open, point(400,100)). opens the picture created above at position 400,100 on the display.

get(+Ref, +Selector, +Args ..., -Value)

Ref is a reference to an existing XPCE object. Selector is the name of a (get-)method defined on (the class of) this object and Args are terms to provide additional arguments. get/[3-13] works similar as send/[2-12] but returns a value rather than succeeding/failing (boolean operation).

For example get(@p, height, H). Unifies H with the height of the graphical window.

free(+Ref)

If Ref is a reference to an XPCE object, invoke send(Ref, free). to the object. Otherwise succeed silently.