Refactor Pass 2. Refactored Gcf out of all backend code.

OceanWolf · tacaswell · Feb 21, 2015 · Feb 22, 2015 · Feb 25, 2015 · Feb 26, 2015
commit 526c2b4e15801811aef3a728b99384741ddae2c4
diff --git a/lib/matplotlib/_pylab_helpers.py b/lib/matplotlib/_pylab_helpers.py
@@ -9,6 +9,8 @@
 import gc
 import atexit
 
+from matplotlib import is_interactive
+
 
 def error_msg(msg):
     print(msg, file=sys.stderr)
@@ -35,6 +37,16 @@ class Gcf(object):
     _activeQue = []
     figs = {}
 
+    @classmethod
+    def add_figure_manager(cls, manager):
+        cls.figs[manager.num] = manager
+        try:  # TODO remove once all backends converted to use the new manager.
+            manager.mpl_connect('window_destroy_event', cls.destroy_cbk)
+        except:
+            pass
+
+        cls.set_active(manager)
+
     @classmethod
     def get_fig_manager(cls, num):
         """
@@ -46,6 +58,49 @@ def get_fig_manager(cls, num):
             cls.set_active(manager)
         return manager
 
+    @classmethod
+    def show_all(cls, block=None):
+        """
+        Show all figures.  If *block* is not None, then
+        it is a boolean that overrides all other factors
+        determining whether show blocks by calling mainloop().
+        The other factors are:
+        it does not block if run inside ipython's "%pylab" mode
+        it does not block in interactive mode.
+        """
+        managers = cls.get_all_fig_managers()
+        if not managers:
+            return
+
+        for manager in managers:
+            manager.show()
+
+        if block is not None:
+            if block:
+                manager.mainloop()
+            return
+
+        from matplotlib import pyplot
+        try:
+            ipython_pylab = not pyplot.show._needmain
+            # IPython versions >= 0.10 tack the _needmain
+            # attribute onto pyplot.show, and always set
+            # it to False, when in %pylab mode.
+            ipython_pylab = ipython_pylab and get_backend() != 'WebAgg'
+            # TODO: The above is a hack to get the WebAgg backend
+            # working with ipython's `%pylab` mode until proper
+            # integration is implemented.
+        except AttributeError:
+            ipython_pylab = False
+
+        # Leave the following as a separate step in case we
+        # want to control this behavior with an rcParam.
+        if ipython_pylab:
+            block = False
+
+        if not is_interactive() or get_backend() == 'WebAgg':
+            manager.mainloop()
+
     @classmethod
     def destroy(cls, num):
         """
@@ -134,7 +189,9 @@ def set_active(cls, manager):
             if m != manager:
                 cls._activeQue.append(m)
         cls._activeQue.append(manager)
-        cls.figs[manager.num] = manager
 
+    @classmethod
+    def destroy_cbk(cls, event):
+        cls.destroy(event.figure_manager.num)
 
 atexit.register(Gcf.destroy_all)
diff --git a/lib/matplotlib/backend_bases.py b/lib/matplotlib/backend_bases.py
@@ -40,7 +40,6 @@
 import io
 
 import numpy as np
-import matplotlib # temporary )assuming we refactor where marked below)
 import matplotlib.cbook as cbook
 import matplotlib.colors as colors
 import matplotlib.transforms as transforms
@@ -133,6 +132,33 @@ def get_registered_canvas_class(format):
     return backend_class
 
 
+class MainLoopBase(object):
+    """This gets used as a key maintaining the event loop.
+    Backends should only need to override begin and end.
+    It should not matter if this gets used as a singleton or not due to
+    clever magic.
+    """
+    _instance_count = {}
+    def __init__(self):
+        MainLoopBase._instance_count.setdefault(self.__class__, 0)
+        MainLoopBase._instance_count[self.__class__] += 1
+
+    def begin(self):
+        pass
+
+    def end(self):
+        pass
+
+    def __call__(self):
+        self.begin()
+
+    def __del__(self):
+        MainLoopBase._instance_count[self.__class__] -= 1
+        if (MainLoopBase._instance_count[self.__class__] <= 0 and
+            not is_interactive()):
+            self.end()
+
+
 class ShowBase(object):
     """
     Simple base class to generate a show() callable in backends.
@@ -2462,7 +2488,10 @@ def key_press_handler(event, canvas, toolbar=None):
 
     # quit the figure (defaut key 'ctrl+w')
     if event.key in quit_keys:
-        Gcf.destroy_fig(canvas.figure)
+        if isinstance(canvas.manager.mainloop, MainLoopBase): # If new no Gcf.
+            canvas.manager._destroy('window_destroy_event')
+        else:
+            Gcf.destroy_fig(canvas.figure)
 
     if toolbar is not None:
         # home or reset mnemonic  (default key 'h', 'home' and 'r')
@@ -2537,20 +2566,16 @@ def key_press_handler(event, canvas, toolbar=None):
 class NonGuiException(Exception):
     pass
 
+
 class WindowEvent(object):
     def __init__(self, name, window):
         self.name = name
         self.window = window
 
-class WindowBase(object):
-    def __init__(self, title):
-        self._callbacks = cbook.CallbackRegistry()
 
-    def mpl_connect(self, s, func):
-        return self._callbacks.connect(s, func)
-
-    def mpl_disconnect(self, cid):
-        return self._callbacks.disconnect(cid)
+class WindowBase(cbook.EventEmitter):
+    def __init__(self, title):
+        cbook.EventEmitter.__init__(self)
 
     def show(self):
         """
@@ -2591,112 +2616,12 @@ def add_element_to_window(self, element, expand, fill, padding, from_start=False
         """
         pass
 
-    def terminate_backend(self):
-        """Method to terminate the usage of the backend
-        """
-        # TODO refactor me out on second pass
-        pass
-
     def destroy_event(self, *args):
         s = 'window_destroy_event'
         event = WindowEvent(s, self)
         self._callbacks.process(s, event)
 
 
-class FigureManager(object):
-    def __init__(self, canvas, num, classes):
-        self._classes = classes
-        self.canvas = canvas
-        canvas.manager = self
-        self.num = num
-
-        self.key_press_handler_id = self.canvas.mpl_connect('key_press_event',
-                                                            self.key_press)
-
-        self.window = classes['Window']('Figure %d' % num)
-        self.window.mpl_connect('window_destroy_event', self._destroy)
-
-        w = int(self.canvas.figure.bbox.width)
-        h = int(self.canvas.figure.bbox.height)
-
-        self.window.add_element_to_window(self.canvas, True, True, 0, True)
-
-        self.toolbar = self._get_toolbar(canvas)
-        if self.toolbar is not None:
-            h += self.window.add_element_to_window(self.toolbar, False, False, 0)
-
-        self.window.set_default_size(w,h)
-
-        # Refactor this?  If so, delete import matplotlib from above.
-        if matplotlib.is_interactive():
-            self.window.show()
-
-        def notify_axes_change(fig):
-            'this will be called whenever the current axes is changed'
-            if self.toolbar is not None: self.toolbar.update()
-        self.canvas.figure.add_axobserver(notify_axes_change)
-
-        self.canvas.grab_focus()
-
-    def key_press(self, event):
-        """
-        Implement the default mpl key bindings defined at
-        :ref:`key-event-handling`
-        """
-        key_press_handler(event, self.canvas, self.canvas.toolbar)
-
-    def _destroy(self, event):
-        Gcf.destroy(self.num) # TODO refactor me out of here on second pass!
-
-    def destroy(self, *args):
-        self.window.destroy()
-        self.canvas.destroy()
-        if self.toolbar:
-            self.toolbar.destroy()
-
-        # TODO refactor out on second pass
-        if Gcf.get_num_fig_managers()==0 and not matplotlib.is_interactive():
-            self.window.terminate_backend()
-
-    def show(self):
-        self.window.show()
-
-    def full_screen_toggle(self):
-        self._full_screen_flag = not self._full_screen_flag
-        self.window.set_fullscreen(self._full_screen_flag)
-
-    def resize(self, w, h):
-        self.window.resize(w,h)
-
-    def get_window_title(self):
-        """
-        Get the title text of the window containing the figure.
-        Return None for non-GUI backends (e.g., a PS backend).
-        """
-        return self.window.get_window_title()
-
-    def set_window_title(self, title):
-        """
-        Set the title text of the window containing the figure.  Note that
-        this has no effect for non-GUI backends (e.g., a PS backend).
-        """
-        self.window.set_window_title(title)
-
-    def show_popup(self, msg):
-        """
-        Display message in a popup -- GUI only
-        """
-        pass
-
-    def _get_toolbar(self, canvas):
-        # must be inited after the window, drawingArea and figure
-        # attrs are set
-        if rcParams['toolbar'] == 'toolbar2':
-            toolbar = self._classes['Toolbar2'](canvas, self.window)
-        else:
-            toolbar = None
-        return toolbar
-
 class FigureManagerBase(object):
     """
     Helper class for pyplot mode, wraps everything up into a neat bundle