Source code for envisage.ui.workbench.workbench_application

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""" The entry point for an Envisage Workbench application. """


# Standard library imports.
import logging

# Enthought library imports.
from envisage.api import Application
from pyface.api import AboutDialog, Dialog, GUI, ImageResource
from pyface.api import SplashScreen
from pyface.workbench.api import IWorkbench
from traits.api import Callable, Instance, Str, Tuple

# Local imports.
from .workbench import Workbench


# Logging.
logger = logging.getLogger(__name__)


[docs]class WorkbenchApplication(Application): """ The entry point for an Envisage Workbench application. i.e. a GUI application whose user interface is provided by the workbench plugin. This class handles the common case for Workbench applications, and it is intended to be subclassed to change start/stop behaviour etc. In fact, I generally create a subclass for every Workbench application I write since it is a good place to put branding information etc. """ #### 'WorkbenchApplication' interface ##################################### # The Pyface GUI for the application (this is here to make it easy for # parts of the application to get a reference to the GUI so they can get # system metrics, etc. gui = Instance(GUI) # The workbench. workbench = Instance(IWorkbench) # The factory for creating the workbench (used *instead* of providing a # workbench explicitly). workbench_factory = Callable(Workbench) # Branding information. # # The 'About' dialog. about_dialog = Instance(Dialog) # The icon used on window title bars etc. icon = Instance(ImageResource, ImageResource("application.ico")) # The name of the application (also used on window title bars etc). name = Str("Workbench") # The splash screen (None, the default, if no splash screen is required). splash_screen = Instance(SplashScreen) # The default position of the main window. window_position = Tuple((200, 200)) # The default size of the main window. window_size = Tuple((800, 600)) ########################################################################### # 'IApplication' interface. ###########################################################################
[docs] def run(self): """ Run the application. This does the following (so you don't have to ;^):- 1) Starts the application 2) Creates and opens a workbench window 3) Starts the GUI event loop 4) When the event loop terminates, stops the application """ logger.debug("---------- workbench application ----------") # Make sure the GUI has been created (so that, if required, the splash # screen is shown). gui = self.gui # Start the application. if self.start(): # Create and open the first workbench window. window = self.workbench.create_window( position=self.window_position, size=self.window_size ) window.open() # We stop the application when the workbench has exited. self.workbench.on_trait_change(self._on_workbench_exited, "exited") # Start the GUI event loop. # # THIS CALL DOES NOT RETURN UNTIL THE GUI IS CLOSED. gui.start_event_loop() return
########################################################################### # 'WorkbenchApplication' interface. ########################################################################### #### Initializers ######################################################### def _about_dialog_default(self): """ Trait initializer. """ return AboutDialog(image=ImageResource("about")) def _gui_default(self): """ Trait initializer. """ return GUI(splash_screen=self.splash_screen) def _workbench_default(self): """ Trait initializer. """ return self.create_workbench() #### Methods ##############################################################
[docs] def about(self): """ Display the about dialog. """ # fixme: We really need to create a new 'about dialog' every time so # that it can have the active window as its parent. self.about_dialog.open() return
# fixme: Is this needed on the public API? Why can't we just do this in # the default initializer (_workbench_default)?
[docs] def create_workbench(self): """ Create the workbench. """ logger.debug("workbench factory %s", self.workbench_factory) return self.workbench_factory(application=self)
[docs] def exit(self): """ Exit the application. This closes all open windows and hence exits the GUI event loop. """ self.workbench.exit() return
########################################################################### # Private interface. ########################################################################### def _on_workbench_exited(self): """ Dynamic trait change handler. """ # We don't invoke 'stop' directly because:- # # The workbench is often exited via a user action (either by closing # the last open window, or by choosing 'File/Exit'). If this happens # then the workbench 'exit' method is called from within an event # handler which would cause the 'stop' method to get called *before* # the handling of the window 'closed' event is complete. Hance, this # might mean that somebody listening for the window being closed would # get the event *after* the application had already stopped! self.gui.invoke_later(self.stop) return