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How to translate button labels

There are two places where you can translate the button labels: from the getButton method of the page, or from the printButton method of the ButtonPart. The former will only affect the specific page, the latter will affect all buttons printed by instances of ButtonPart. For an example of overriding getButton methods, see example 10.

You probably first need to subclass the page or part class, see how to specialize a part of a page.