Source code for pyface.wizard.chained_wizard_controller

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""" A wizard controller that can be chained with others. """


from traits.api import Instance, observe


from .i_wizard_controller import IWizardController
from .wizard_controller import WizardController


[docs]class ChainedWizardController(WizardController): """ A wizard controller that can be chained with others. """ # 'ChainedWizardController' interface ---------------------------------# # The next chained wizard controller. next_controller = Instance(IWizardController) # ------------------------------------------------------------------------ # 'IWizardController' interface. # ------------------------------------------------------------------------
[docs] def get_next_page(self, page): """ Returns the next page. """ next_page = None if page in self._pages: if page is not self._pages[-1]: index = self._pages.index(page) next_page = self._pages[index + 1] else: if self.next_controller is not None: next_page = self.next_controller.get_first_page() else: if self.next_controller is not None: next_page = self.next_controller.get_next_page(page) return next_page
[docs] def get_previous_page(self, page): """ Returns the previous page. """ if page in self._pages: index = self._pages.index(page) previous_page = self._pages[index - 1] else: if self.next_controller is not None: if self.next_controller.is_first_page(page): previous_page = self._pages[-1] else: previous_page = self.next_controller.get_previous_page( page ) else: previous_page = None return previous_page
[docs] def is_first_page(self, page): """ Is the page the first page? """ return page is self._pages[0]
[docs] def is_last_page(self, page): """ Is the page the last page? """ if page in self._pages: # If page is not this controller's last page, then it cannot be # *the* last page. if page is not self._pages[-1]: is_last = False # Otherwise, it is *the* last page if this controller has no next # controller or the next controller has no pages. else: if self.next_controller is None: is_last = True else: is_last = self.next_controller.is_last_page(page) else: if self.next_controller is not None: is_last = self.next_controller.is_last_page(page) elif len(self._pages) > 0: is_last = False else: is_last = True return is_last
[docs] def dispose_pages(self): """ Dispose the wizard's pages. """ for page in self._pages: page.dispose_page() if self.next_controller is not None: self.next_controller.dispose_pages() return
# ------------------------------------------------------------------------ # 'ChainedWizardController' interface. # ------------------------------------------------------------------------ def _get_pages(self): """ Returns the pages in the wizard. """ pages = self._pages[:] if self.next_controller is not None: pages.extend(self.next_controller.pages) return pages def _set_pages(self, pages): """ Sets the pages in the wizard. """ self._pages = pages return # ------------------------------------------------------------------------ # Private interface. # ------------------------------------------------------------------------ def _update(self): """ Checks the completion status of the controller. """ # The entire wizard is complete when ALL pages are complete. for page in self._pages: if not page.complete: self.complete = False break else: if self.next_controller is not None: # fixme: This is a abstraction leak point, since _update is not # part of the wizard_controller interface! self.next_controller._update() self.complete = self.next_controller.complete else: self.complete = True return # Trait event handlers ------------------------------------------------- # Static ---- @observe("current_page") def _reset_observers_on_current_page_and_update(self, event): """ Called when the current page is changed. """ old, new = event.old, event.new if old is not None: old.observe( self._on_page_complete, "complete", remove=True ) if new is not None: new.observe(self._on_page_complete, "complete") if self.next_controller is not None: self.next_controller.current_page = new self._update() @observe("next_controller") def _reset_observers_on_next_controller_and_update(self, event): """ Called when the next controller is changed. """ old, new = event.old, event.new if old is not None: old.observe( self._on_controller_complete, "complete", remove=True ) if new is not None: new.observe(self._on_controller_complete, "complete") self._update() return # Dynamic ---- def _on_controller_complete(self, event): """ Called when the next controller's complete state changes. """ self._update() def _on_page_complete(self, event): """ Called when the current page is complete. """ self._update() return