backend_gtk3.py

from __future__ import division

import os, sys
def fn_name(): return sys._getframe(1).f_code.co_name

try:
    from gi.repository import Gtk, Gdk, GObject
except ImportError:
    raise ImportError("GTK3 backend requires pygobject to be installed.")

import matplotlib
from matplotlib._pylab_helpers import Gcf
from matplotlib.backend_bases import RendererBase, GraphicsContextBase, \
     FigureManagerBase, FigureCanvasBase, NavigationToolbar2, cursors, TimerBase
from matplotlib.backend_bases import ShowBase

from matplotlib.cbook import is_string_like, is_writable_file_like
from matplotlib.colors import colorConverter
from matplotlib.figure import Figure
from matplotlib.widgets import SubplotTool

from matplotlib import lines
from matplotlib import cbook
from matplotlib import verbose
from matplotlib import rcParams

backend_version = "%s.%s.%s" % (Gtk.get_major_version(), Gtk.get_micro_version(), Gtk.get_minor_version())

_debug = False
#_debug = True

# the true dots per inch on the screen; should be display dependent
# see http://groups.google.com/groups?q=screen+dpi+x11&hl=en&lr=&ie=UTF-8&oe=UTF-8&safe=off&selm=7077.26e81ad5%40swift.cs.tcd.ie&rnum=5 for some info about screen dpi
PIXELS_PER_INCH = 96

cursord = {
    cursors.MOVE          : Gdk.Cursor.new(Gdk.CursorType.FLEUR),
    cursors.HAND          : Gdk.Cursor.new(Gdk.CursorType.HAND2),
    cursors.POINTER       : Gdk.Cursor.new(Gdk.CursorType.LEFT_PTR),
    cursors.SELECT_REGION : Gdk.Cursor.new(Gdk.CursorType.TCROSS),
    }

def draw_if_interactive():
    """
    Is called after every pylab drawing command
    """
    if matplotlib.is_interactive():
        figManager =  Gcf.get_active()
        if figManager is not None:
            figManager.canvas.draw_idle()

class Show(ShowBase):
    def mainloop(self):
        if Gtk.main_level() == 0:
            Gtk.main()

show = Show()


class TimerGTK3(TimerBase):
    '''
    Subclass of :class:`backend_bases.TimerBase` that uses GTK3 for timer events.

    Attributes:
    * interval: The time between timer events in milliseconds. Default
        is 1000 ms.
    * single_shot: Boolean flag indicating whether this timer should
        operate as single shot (run once and then stop). Defaults to False.
    * callbacks: Stores list of (func, args) tuples that will be called
        upon timer events. This list can be manipulated directly, or the
        functions add_callback and remove_callback can be used.
    '''
    def _timer_start(self):
        # Need to stop it, otherwise we potentially leak a timer id that will
        # never be stopped.
        self._timer_stop()
        self._timer = GObject.timeout_add(self._interval, self._on_timer)

    def _timer_stop(self):
        if self._timer is not None:
            GObject.source_remove(self._timer)
            self._timer = None

    def _timer_set_interval(self):
        # Only stop and restart it if the timer has already been started
        if self._timer is not None:
            self._timer_stop()
            self._timer_start()

    def _on_timer(self):
        TimerBase._on_timer(self)

        # Gtk timeout_add() requires that the callback returns True if it
        # is to be called again.
        if len(self.callbacks) > 0 and not self._single:
            return True
        else:
            self._timer = None
            return False

class FigureCanvasGTK3 (Gtk.DrawingArea, FigureCanvasBase):
    keyvald = {65507 : 'control',
               65505 : 'shift',
               65513 : 'alt',
               65508 : 'control',
               65506 : 'shift',
               65514 : 'alt',
               65361 : 'left',
               65362 : 'up',
               65363 : 'right',
               65364 : 'down',
               65307 : 'escape',
               65470 : 'f1',
               65471 : 'f2',
               65472 : 'f3',
               65473 : 'f4',
               65474 : 'f5',
               65475 : 'f6',
               65476 : 'f7',
               65477 : 'f8',
               65478 : 'f9',
               65479 : 'f10',
               65480 : 'f11',
               65481 : 'f12',
               65300 : 'scroll_lock',
               65299 : 'break',
               65288 : 'backspace',
               65293 : 'enter',
               65379 : 'insert',
               65535 : 'delete',
               65360 : 'home',
               65367 : 'end',
               65365 : 'pageup',
               65366 : 'pagedown',
               65438 : '0',
               65436 : '1',
               65433 : '2',
               65435 : '3',
               65430 : '4',
               65437 : '5',
               65432 : '6',
               65429 : '7',
               65431 : '8',
               65434 : '9',
               65451 : '+',
               65453 : '-',
               65450 : '*',
               65455 : '/',
               65439 : 'dec',
               65421 : 'enter',
               }

    # Setting this as a static constant prevents
    # this resulting expression from leaking
    event_mask = (Gdk.EventMask.BUTTON_PRESS_MASK   |
                  Gdk.EventMask.BUTTON_RELEASE_MASK |
                  Gdk.EventMask.EXPOSURE_MASK       |
                  Gdk.EventMask.KEY_PRESS_MASK      |
                  Gdk.EventMask.KEY_RELEASE_MASK    |
                  Gdk.EventMask.ENTER_NOTIFY_MASK   |
                  Gdk.EventMask.LEAVE_NOTIFY_MASK   |
                  Gdk.EventMask.POINTER_MOTION_MASK |
                  Gdk.EventMask.POINTER_MOTION_HINT_MASK)

    def __init__(self, figure):
        if _debug: print 'FigureCanvasGTK3.%s' % fn_name()
        FigureCanvasBase.__init__(self, figure)
        GObject.GObject.__init__(self)

        self._idle_draw_id  = 0
        self._need_redraw   = True
        self._lastCursor    = None

        self.connect('scroll_event',         self.scroll_event)
        self.connect('button_press_event',   self.button_press_event)
        self.connect('button_release_event', self.button_release_event)
        self.connect('configure_event',      self.configure_event)
        self.connect('draw',                 self.on_draw_event)
        self.connect('key_press_event',      self.key_press_event)
        self.connect('key_release_event',    self.key_release_event)
        self.connect('motion_notify_event',  self.motion_notify_event)
        self.connect('leave_notify_event',   self.leave_notify_event)
        self.connect('enter_notify_event',   self.enter_notify_event)

        self.set_events(self.__class__.event_mask)

        self.set_double_buffered(True)
        self.set_can_focus(True)
        self._renderer_init()
        self._idle_event_id = GObject.idle_add(self.idle_event)

    def destroy(self):
        #Gtk.DrawingArea.destroy(self)
        self.close_event()
        GObject.source_remove(self._idle_event_id)
        if self._idle_draw_id != 0:
            GObject.source_remove(self._idle_draw_id)

    def scroll_event(self, widget, event):
        if _debug: print 'FigureCanvasGTK3.%s' % fn_name()
        x = event.x
        # flipy so y=0 is bottom of canvas
        y = self.get_allocation().height - event.y
        if event.direction==Gdk.ScrollDirection.UP:
            step = 1
        else:
            step = -1
        FigureCanvasBase.scroll_event(self, x, y, step, guiEvent=event)
        return False  # finish event propagation?

    def button_press_event(self, widget, event):
        if _debug: print 'FigureCanvasGTK3.%s' % fn_name()
        x = event.x
        # flipy so y=0 is bottom of canvas
        y = self.get_allocation().height - event.y
        FigureCanvasBase.button_press_event(self, x, y, event.button, guiEvent=event)
        return False  # finish event propagation?

    def button_release_event(self, widget, event):
        if _debug: print 'FigureCanvasGTK3.%s' % fn_name()
        x = event.x
        # flipy so y=0 is bottom of canvas
        y = self.get_allocation().height - event.y
        FigureCanvasBase.button_release_event(self, x, y, event.button, guiEvent=event)
        return False  # finish event propagation?

    def key_press_event(self, widget, event):
        if _debug: print 'FigureCanvasGTK3.%s' % fn_name()
        key = self._get_key(event)
        if _debug: print "hit", key
        FigureCanvasBase.key_press_event(self, key, guiEvent=event)
        return False  # finish event propagation?

    def key_release_event(self, widget, event):
        if _debug: print 'FigureCanvasGTK3.%s' % fn_name()
        key = self._get_key(event)
        if _debug: print "release", key
        FigureCanvasBase.key_release_event(self, key, guiEvent=event)
        return False  # finish event propagation?

    def motion_notify_event(self, widget, event):
        if _debug: print 'FigureCanvasGTK3.%s' % fn_name()
        if event.is_hint:
            t, x, y, state = event.window.get_pointer()
        else:
            x, y, state = event.x, event.y, event.get_state()

        # flipy so y=0 is bottom of canvas
        y = self.get_allocation().height - y
        FigureCanvasBase.motion_notify_event(self, x, y, guiEvent=event)
        return False  # finish event propagation?

    def leave_notify_event(self, widget, event):
        FigureCanvasBase.leave_notify_event(self, event)

    def enter_notify_event(self, widget, event):
        FigureCanvasBase.enter_notify_event(self, event)

    def _get_key(self, event):
        if event.keyval in self.keyvald:
            key = self.keyvald[event.keyval]
        elif event.keyval < 256:
            key = chr(event.keyval)
        else:
            key = None

        modifiers = [
                     (Gdk.ModifierType.MOD4_MASK, 'super'),
                     (Gdk.ModifierType.MOD1_MASK, 'alt'),
                     (Gdk.ModifierType.CONTROL_MASK, 'ctrl'),
                    ]
        for key_mask, prefix in modifiers:
            if event.state & key_mask:
                key = '{}+{}'.format(prefix, key)

        return key

    def configure_event(self, widget, event):
        if _debug: print 'FigureCanvasGTK3.%s' % fn_name()
        if widget.get_property("window") is None:
            return
        w, h = event.width, event.height
        if w < 3 or h < 3:
            return # empty fig

        # resize the figure (in inches)
        dpi = self.figure.dpi
        self.figure.set_size_inches (w/dpi, h/dpi)
        self._need_redraw = True

        return False  # finish event propagation?

    def on_draw_event(self, widget, ctx):
        # to be overwritten by GTK3Agg or GTK3Cairo
        pass

    def draw(self):
        self._need_redraw = True
        if self.get_visible() and self.get_mapped():
            self.queue_draw()
            # do a synchronous draw (its less efficient than an async draw,
            # but is required if/when animation is used)
            self.get_property("window").process_updates (False)

    def draw_idle(self):
        def idle_draw(*args):
            self.draw()
            self._idle_draw_id = 0
            return False
        if self._idle_draw_id == 0:
            self._idle_draw_id = GObject.idle_add(idle_draw)

    def new_timer(self, *args, **kwargs):
        """
        Creates a new backend-specific subclass of :class:`backend_bases.Timer`.
        This is useful for getting periodic events through the backend's native
        event loop. Implemented only for backends with GUIs.

        optional arguments:

        *interval*
          Timer interval in milliseconds
        *callbacks*
          Sequence of (func, args, kwargs) where func(*args, **kwargs) will
          be executed by the timer every *interval*.
        """
        return TimerGTK3(*args, **kwargs)

    def flush_events(self):
        Gdk.threads_enter()
        while Gtk.events_pending():
            Gtk.main_iteration(True)
        Gdk.flush()
        Gdk.threads_leave()

    def start_event_loop(self,timeout):
        FigureCanvasBase.start_event_loop_default(self,timeout)
    start_event_loop.__doc__=FigureCanvasBase.start_event_loop_default.__doc__

    def stop_event_loop(self):
        FigureCanvasBase.stop_event_loop_default(self)
    stop_event_loop.__doc__=FigureCanvasBase.stop_event_loop_default.__doc__

FigureCanvas = FigureCanvasGTK3

class FigureManagerGTK3(FigureManagerBase):
    """
    Public attributes

    canvas      : The FigureCanvas instance
    num         : The Figure number
    toolbar     : The Gtk.Toolbar  (gtk only)
    vbox        : The Gtk.VBox containing the canvas and toolbar (gtk only)
    window      : The Gtk.Window   (gtk only)
    """
    def __init__(self, canvas, num):
        if _debug: print 'FigureManagerGTK3.%s' % fn_name()
        FigureManagerBase.__init__(self, canvas, num)

        self.window = Gtk.Window()
        self.set_window_title("Figure %d" % num)
        try:
            self.window.set_icon_from_file(window_icon)
        except (SystemExit, KeyboardInterrupt):
            # re-raise exit type Exceptions
            raise
        except:
            # some versions of gtk throw a glib.GError but not
            # all, so I am not sure how to catch it.  I am unhappy
            # doing a blanket catch here, but am not sure what a
            # better way is - JDH
            verbose.report('Could not load matplotlib icon: %s' % sys.exc_info()[1])

        self.vbox = Gtk.Box()
        self.vbox.set_property("orientation", Gtk.Orientation.VERTICAL)
        self.window.add(self.vbox)
        self.vbox.show()

        self.canvas.show()

        self.vbox.pack_start(self.canvas, True, True, 0)

        self.toolbar = self._get_toolbar(canvas)

        # calculate size for window
        w = int (self.canvas.figure.bbox.width)
        h = int (self.canvas.figure.bbox.height)

        if self.toolbar is not None:
            self.toolbar.show()
            self.vbox.pack_end(self.toolbar, False, False, 0)
            size_request = self.toolbar.size_request()
            h += size_request.height

        self.window.set_default_size (w, h)

        def destroy(*args):
            Gcf.destroy(num)
        self.window.connect("destroy", destroy)
        self.window.connect("delete_event", destroy)
        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 destroy(self, *args):
        if _debug: print 'FigureManagerGTK3.%s' % fn_name()
        self.vbox.destroy()
        self.window.destroy()
        self.canvas.destroy()
        if self.toolbar:
            self.toolbar.destroy()
        self.__dict__.clear()   #Is this needed? Other backends don't have it.

        if Gcf.get_num_fig_managers()==0 and \
               not matplotlib.is_interactive() and \
               Gtk.main_level() >= 1:
            Gtk.main_quit()

    def show(self):
        # show the figure window
        self.window.show()

    def full_screen_toggle (self):
        self._full_screen_flag = not self._full_screen_flag
        if self._full_screen_flag:
            self.window.fullscreen()
        else:
            self.window.unfullscreen()
    _full_screen_flag = False


    def _get_toolbar(self, canvas):
        # must be inited after the window, drawingArea and figure
        # attrs are set
        if rcParams['toolbar'] == 'classic':
            toolbar = NavigationToolbar (canvas, self.window)
        elif rcParams['toolbar'] == 'toolbar2':
            toolbar = NavigationToolbar2GTK3 (canvas, self.window)
        else:
            toolbar = None
        return toolbar

    def get_window_title(self):
        return self.window.get_title()

    def set_window_title(self, title):
        self.window.set_title(title)

    def resize(self, width, height):
        'set the canvas size in pixels'
        #_, _, cw, ch = self.canvas.allocation
        #_, _, ww, wh = self.window.allocation
        #self.window.resize (width-cw+ww, height-ch+wh)
        self.window.resize(width, height)


class NavigationToolbar2GTK3(NavigationToolbar2, Gtk.Toolbar):
    def __init__(self, canvas, window):
        self.win = window
        GObject.GObject.__init__(self)
        NavigationToolbar2.__init__(self, canvas)
        self.ctx = None

    def set_message(self, s):
        self.message.set_label(s)

    def set_cursor(self, cursor):
        self.canvas.get_property("window").set_cursor(cursord[cursor])
        #self.canvas.set_cursor(cursord[cursor])

    def release(self, event):
        try: del self._pixmapBack
        except AttributeError: pass

    def dynamic_update(self):
        # legacy method; new method is canvas.draw_idle
        self.canvas.draw_idle()

    def draw_rubberband(self, event, x0, y0, x1, y1):
        'adapted from http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/189744'
        self.ctx = self.canvas.get_property("window").cairo_create()

        # todo: instead of redrawing the entire figure, copy the part of
        # the figure that was covered by the previous rubberband rectangle
        self.canvas.draw()

        height = self.canvas.figure.bbox.height
        y1 = height - y1
        y0 = height - y0
        w = abs(x1 - x0)
        h = abs(y1 - y0)
        rect = [int(val)for val in min(x0,x1), min(y0, y1), w, h]

        self.ctx.new_path()
        self.ctx.set_line_width(0.5)
        self.ctx.rectangle(rect[0], rect[1], rect[2], rect[3])
        self.ctx.set_source_rgb(0, 0, 0)
        self.ctx.stroke()

    def _init_toolbar(self):
        self.set_style(Gtk.ToolbarStyle.ICONS)
        basedir = os.path.join(rcParams['datapath'],'images')

        for text, tooltip_text, image_file, callback in self.toolitems:
            if text is None:
                self.insert( Gtk.SeparatorToolItem(), -1 )
                continue
            fname = os.path.join(basedir, image_file + '.png')
            image = Gtk.Image()
            image.set_from_file(fname)
            tbutton = Gtk.ToolButton()
            tbutton.set_label(text)
            tbutton.set_icon_widget(image)
            self.insert(tbutton, -1)
            tbutton.connect('clicked', getattr(self, callback))
            tbutton.set_tooltip_text(tooltip_text)

        toolitem = Gtk.SeparatorToolItem()
        self.insert(toolitem, -1)
        toolitem.set_draw(False)
        toolitem.set_expand(True)

        toolitem = Gtk.ToolItem()
        self.insert(toolitem, -1)
        self.message = Gtk.Label()
        toolitem.add(self.message)

        self.show_all()

    def get_filechooser(self):
        fc = FileChooserDialog(
            title='Save the figure',
            parent=self.win,
            filetypes=self.canvas.get_supported_filetypes(),
            default_filetype=self.canvas.get_default_filetype())
        fc.set_current_name(self.canvas.get_default_filename())
        return fc

    def save_figure(self, *args):
        fname, format = self.get_filechooser().get_filename_from_user()
        if fname:
            try:
                self.canvas.print_figure(fname, format=format)
            except Exception, e:
                error_msg_gtk(str(e), parent=self)

    def configure_subplots(self, button):
        toolfig = Figure(figsize=(6,3))
        canvas = self._get_canvas(toolfig)
        toolfig.subplots_adjust(top=0.9)
        tool =  SubplotTool(self.canvas.figure, toolfig)

        w = int (toolfig.bbox.width)
        h = int (toolfig.bbox.height)


        window = Gtk.Window()
        try:
            window.set_icon_from_file(window_icon)
        except (SystemExit, KeyboardInterrupt):
            # re-raise exit type Exceptions
            raise
        except:
            # we presumably already logged a message on the
            # failure of the main plot, don't keep reporting
            pass
        window.set_title("Subplot Configuration Tool")
        window.set_default_size(w, h)
        vbox = Gtk.Box()
        vbox.set_property("orientation", Gtk.Orientation.VERTICAL)
        window.add(vbox)
        vbox.show()

        canvas.show()
        vbox.pack_start(canvas, True, True, 0)
        window.show()

    def _get_canvas(self, fig):
        return self.canvas.__class__(fig)


class NavigationToolbar(Gtk.Toolbar):
    """
    Public attributes

      canvas - the FigureCanvas  (Gtk.DrawingArea)
      win    - the Gtk.Window

    """
    # list of toolitems to add to the toolbar, format is:
    # text, tooltip_text, image, callback(str), callback_arg, scroll(bool)
    toolitems = (
        ('Left', 'Pan left with click or wheel mouse (bidirectional)',
         Gtk.STOCK_GO_BACK, 'panx', -1, True),
        ('Right', 'Pan right with click or wheel mouse (bidirectional)',
         Gtk.STOCK_GO_FORWARD, 'panx', 1, True),
        ('Zoom In X',
         'Zoom In X (shrink the x axis limits) with click or wheel'
         ' mouse (bidirectional)',
         Gtk.STOCK_ZOOM_IN, 'zoomx', 1, True),
        ('Zoom Out X',
         'Zoom Out X (expand the x axis limits) with click or wheel'
         ' mouse (bidirectional)',
         Gtk.STOCK_ZOOM_OUT, 'zoomx', -1, True),
        (None, None, None, None, None, None,),
        ('Up', 'Pan up with click or wheel mouse (bidirectional)',
         Gtk.STOCK_GO_UP, 'pany', 1, True),
        ('Down', 'Pan down with click or wheel mouse (bidirectional)',
         Gtk.STOCK_GO_DOWN, 'pany', -1, True),
        ('Zoom In Y',
         'Zoom in Y (shrink the y axis limits) with click or wheel'
         ' mouse (bidirectional)',
         Gtk.STOCK_ZOOM_IN, 'zoomy', 1, True),
        ('Zoom Out Y',
         'Zoom Out Y (expand the y axis limits) with click or wheel'
         ' mouse (bidirectional)',
         Gtk.STOCK_ZOOM_OUT, 'zoomy', -1, True),
        (None, None, None, None, None, None,),
        ('Save', 'Save the figure',
         Gtk.STOCK_SAVE, 'save_figure', None, False),
        )

    def __init__(self, canvas, window):
        """
        figManager is the FigureManagerGTK3 instance that contains the
        toolbar, with attributes figure, window and drawingArea

        """
        GObject.GObject.__init__(self)

        self.canvas = canvas
        # Note: Gtk.Toolbar already has a 'window' attribute
        self.win    = window

        self.set_style(Gtk.ToolbarStyle.ICONS)

        self._create_toolitems()
        self.update = self._update
        self.fileselect = FileChooserDialog(
            title='Save the figure',
            parent=self.win,
            filetypes=self.canvas.get_supported_filetypes(),
            default_filetype=self.canvas.get_default_filetype())
        self.show_all()
        self.update()

    def _create_toolitems(self):
        iconSize = Gtk.IconSize.SMALL_TOOLBAR

        for text, tooltip_text, image_num, callback, callback_arg, scroll \
                in self.toolitems:
            if text is None:
                self.insert( Gtk.SeparatorToolItem(), -1 )
                continue
            image = Gtk.Image()
            image.set_from_stock(image_num, iconSize)
            tbutton = Gtk.ToolButton()
            tbutton.set_label(text)
            tbutton.set_icon_widget(image)
            self.insert(tbutton, -1)
            if callback_arg:
                tbutton.connect('clicked', getattr(self, callback),
                                callback_arg)
            else:
                tbutton.connect('clicked', getattr(self, callback))
            if scroll:
                tbutton.connect('scroll_event', getattr(self, callback))
            tbutton.set_tooltip_text(tooltip_text)

        # Axes toolitem, is empty at start, update() adds a menu if >=2 axes
        self.axes_toolitem = Gtk.ToolItem()
        self.insert(self.axes_toolitem, 0)
        self.axes_toolitem.set_tooltip_text(
                            'Select axes that controls affect')

        align = Gtk.Alignment (xalign=0.5, yalign=0.5, xscale=0.0, yscale=0.0)
        self.axes_toolitem.add(align)

        self.menubutton = Gtk.Button ("Axes")
        align.add (self.menubutton)

        def position_menu (menu):
            """Function for positioning a popup menu.
            Place menu below the menu button, but ensure it does not go off
            the bottom of the screen.
            The default is to popup menu at current mouse position
            """
            x0, y0    = self.window.get_origin()
            x1, y1, m = self.window.get_pointer()
            x2, y2    = self.menubutton.get_pointer()
            sc_h      = self.get_screen().get_height()
            w, h      = menu.size_request()

            x = x0 + x1 - x2
            y = y0 + y1 - y2 + self.menubutton.allocation.height
            y = min(y, sc_h - h)
            return x, y, True

        def button_clicked (button, data=None):
            self.axismenu.popup (None, None, position_menu, 0,
                                 Gtk.get_current_event_time())

        self.menubutton.connect ("clicked", button_clicked)


    def _update(self):
        # called by __init__() and FigureManagerGTK3

        self._axes = self.canvas.figure.axes

        if len(self._axes) >= 2:
            self.axismenu = self._make_axis_menu()
            self.menubutton.show_all()
        else:
            self.menubutton.hide()

        self.set_active(range(len(self._axes)))


    def _make_axis_menu(self):
        # called by self._update*()

        def toggled(item, data=None):
            if item == self.itemAll:
                for item in items: item.set_active(True)
            elif item == self.itemInvert:
                for item in items:
                    item.set_active(not item.get_active())

            ind = [i for i,item in enumerate(items) if item.get_active()]
            self.set_active(ind)

        menu = Gtk.Menu()

        self.itemAll = Gtk.MenuItem("All")
        menu.append(self.itemAll)
        self.itemAll.connect("activate", toggled)

        self.itemInvert = Gtk.MenuItem("Invert")
        menu.append(self.itemInvert)
        self.itemInvert.connect("activate", toggled)

        items = []
        for i in range(len(self._axes)):
            item = Gtk.CheckMenuItem("Axis %d" % (i+1))
            menu.append(item)
            item.connect("toggled", toggled)
            item.set_active(True)
            items.append(item)

        menu.show_all()
        return menu


    def set_active(self, ind):
        self._ind = ind
        self._active = [ self._axes[i] for i in self._ind ]

    def panx(self, button, direction):
        'panx in direction'

        for a in self._active:
            a.xaxis.pan(direction)
        self.canvas.draw()
        self._need_redraw = True
        return True

    def pany(self, button, direction):
        'pany in direction'
        for a in self._active:
            a.yaxis.pan(direction)
        self.canvas.draw()
        return True

    def zoomx(self, button, direction):
        'zoomx in direction'
        for a in self._active:
            a.xaxis.zoom(direction)
        self.canvas.draw()
        return True

    def zoomy(self, button, direction):
        'zoomy in direction'
        for a in self._active:
            a.yaxis.zoom(direction)
        self.canvas.draw()
        return True

    def get_filechooser(self):
        return FileChooserDialog(
            title='Save the figure',
            parent=self.win,
            filetypes=self.canvas.get_supported_filetypes(),
            default_filetype=self.canvas.get_default_filetype())

    def save_figure(self, *args):
        fname, format = self.get_filechooser().get_filename_from_user()
        if fname:
            try:
                self.canvas.print_figure(fname, format=format)
            except Exception, e:
                error_msg_gtk(str(e), parent=self)


class FileChooserDialog(Gtk.FileChooserDialog):
    """GTK+ file selector which remembers the last file/directory
    selected and presents the user with a menu of supported image formats
    """
    def __init__ (self,
                  title   = 'Save file',
                  parent  = None,
                  action  = Gtk.FileChooserAction.SAVE,
                  buttons = (Gtk.STOCK_CANCEL, Gtk.ResponseType.CANCEL,
                             Gtk.STOCK_SAVE,   Gtk.ResponseType.OK),
                  path    = None,
                  filetypes = [],
                  default_filetype = None
                  ):
        super (FileChooserDialog, self).__init__ (title, parent, action,
                                                  buttons)
        self.set_default_response (Gtk.ResponseType.OK)

        if not path: path = os.getcwd() + os.sep

        # create an extra widget to list supported image formats
        self.set_current_folder (path)
        self.set_current_name ('image.' + default_filetype)

        hbox = Gtk.Box(spacing=10)
        hbox.pack_start(Gtk.Label(label="File Format:"), False, False, 0)

        liststore = Gtk.ListStore(GObject.TYPE_STRING)
        cbox = Gtk.ComboBox() #liststore)
        cbox.set_model(liststore)
        cell = Gtk.CellRendererText()
        cbox.pack_start(cell, True)
        cbox.add_attribute(cell, 'text', 0)
        hbox.pack_start(cbox, False, False, 0)

        self.filetypes = filetypes
        self.sorted_filetypes = filetypes.items()
        self.sorted_filetypes.sort()
        default = 0
        for i, (ext, name) in enumerate(self.sorted_filetypes):
            liststore.append(["%s (*.%s)" % (name, ext)])
            if ext == default_filetype:
                default = i
        cbox.set_active(default)
        self.ext = default_filetype

        def cb_cbox_changed (cbox, data=None):
            """File extension changed"""
            head, filename = os.path.split(self.get_filename())
            root, ext = os.path.splitext(filename)
            ext = ext[1:]
            new_ext = self.sorted_filetypes[cbox.get_active()][0]
            self.ext = new_ext

            if ext in self.filetypes:
                filename = root + '.' + new_ext
            elif ext == '':
                filename = filename.rstrip('.') + '.' + new_ext

            self.set_current_name (filename)
        cbox.connect ("changed", cb_cbox_changed)

        hbox.show_all()
        self.set_extra_widget(hbox)

    def get_filename_from_user (self):
        while True:
            filename = None
            if self.run() != int(Gtk.ResponseType.OK):
                break
            filename = self.get_filename()
            break

        self.hide()
        return filename, self.ext

class DialogLineprops:
    """
    A GUI dialog for controlling lineprops
    """
    signals = (
        'on_combobox_lineprops_changed',
        'on_combobox_linestyle_changed',
        'on_combobox_marker_changed',
        'on_colorbutton_linestyle_color_set',
        'on_colorbutton_markerface_color_set',
        'on_dialog_lineprops_okbutton_clicked',
        'on_dialog_lineprops_cancelbutton_clicked',
        )

    linestyles = [ls for ls in lines.Line2D.lineStyles if ls.strip()]
    linestyled = dict([ (s,i) for i,s in enumerate(linestyles)])


    markers =  [m for m in lines.Line2D.markers if cbook.is_string_like(m)]

    markerd = dict([(s,i) for i,s in enumerate(markers)])

    def __init__(self, lines):
        import Gtk.glade

        datadir = matplotlib.get_data_path()
        gladefile = os.path.join(datadir, 'lineprops.glade')
        if not os.path.exists(gladefile):
            raise IOError('Could not find gladefile lineprops.glade in %s'%datadir)

        self._inited = False
        self._updateson = True # suppress updates when setting widgets manually
        self.wtree = Gtk.glade.XML(gladefile, 'dialog_lineprops')
        self.wtree.signal_autoconnect(dict([(s, getattr(self, s)) for s in self.signals]))

        self.dlg = self.wtree.get_widget('dialog_lineprops')

        self.lines = lines

        cbox = self.wtree.get_widget('combobox_lineprops')
        cbox.set_active(0)
        self.cbox_lineprops = cbox

        cbox = self.wtree.get_widget('combobox_linestyles')
        for ls in self.linestyles:
            cbox.append_text(ls)
        cbox.set_active(0)
        self.cbox_linestyles = cbox

        cbox = self.wtree.get_widget('combobox_markers')
        for m in self.markers:
            cbox.append_text(m)
        cbox.set_active(0)
        self.cbox_markers = cbox
        self._lastcnt = 0
        self._inited = True


    def show(self):
        'populate the combo box'
        self._updateson = False
        # flush the old
        cbox = self.cbox_lineprops
        for i in range(self._lastcnt-1,-1,-1):
            cbox.remove_text(i)

        # add the new
        for line in self.lines:
            cbox.append_text(line.get_label())
        cbox.set_active(0)

        self._updateson = True
        self._lastcnt = len(self.lines)
        self.dlg.show()

    def get_active_line(self):
        'get the active line'
        ind = self.cbox_lineprops.get_active()
        line = self.lines[ind]
        return line

    def get_active_linestyle(self):
        'get the active lineinestyle'
        ind = self.cbox_linestyles.get_active()
        ls = self.linestyles[ind]
        return ls

    def get_active_marker(self):
        'get the active lineinestyle'
        ind = self.cbox_markers.get_active()
        m = self.markers[ind]
        return m

    def _update(self):
        'update the active line props from the widgets'
        if not self._inited or not self._updateson: return
        line = self.get_active_line()
        ls = self.get_active_linestyle()
        marker = self.get_active_marker()
        line.set_linestyle(ls)
        line.set_marker(marker)

        button = self.wtree.get_widget('colorbutton_linestyle')
        color = button.get_color()
        r, g, b = [val/65535. for val in color.red, color.green, color.blue]
        line.set_color((r,g,b))

        button = self.wtree.get_widget('colorbutton_markerface')
        color = button.get_color()
        r, g, b = [val/65535. for val in color.red, color.green, color.blue]
        line.set_markerfacecolor((r,g,b))

        line.figure.canvas.draw()

    def on_combobox_lineprops_changed(self, item):
        'update the widgets from the active line'
        if not self._inited: return
        self._updateson = False
        line = self.get_active_line()

        ls = line.get_linestyle()
        if ls is None: ls = 'None'
        self.cbox_linestyles.set_active(self.linestyled[ls])

        marker = line.get_marker()
        if marker is None: marker = 'None'
        self.cbox_markers.set_active(self.markerd[marker])

        r,g,b = colorConverter.to_rgb(line.get_color())
        color = Gdk.Color(*[int(val*65535) for val in r,g,b])
        button = self.wtree.get_widget('colorbutton_linestyle')
        button.set_color(color)

        r,g,b = colorConverter.to_rgb(line.get_markerfacecolor())
        color = Gdk.Color(*[int(val*65535) for val in r,g,b])
        button = self.wtree.get_widget('colorbutton_markerface')
        button.set_color(color)
        self._updateson = True

    def on_combobox_linestyle_changed(self, item):
        self._update()

    def on_combobox_marker_changed(self, item):
        self._update()

    def on_colorbutton_linestyle_color_set(self, button):
        self._update()

    def on_colorbutton_markerface_color_set(self, button):
        'called colorbutton marker clicked'
        self._update()

    def on_dialog_lineprops_okbutton_clicked(self, button):
        self._update()
        self.dlg.hide()

    def on_dialog_lineprops_cancelbutton_clicked(self, button):
        self.dlg.hide()


# Define the file to use as the GTk icon
if sys.platform == 'win32':
    icon_filename = 'matplotlib.png'
else:
    icon_filename = 'matplotlib.svg'
window_icon = os.path.join(matplotlib.rcParams['datapath'], 'images', icon_filename)


def error_msg_gtk(msg, parent=None):
    if parent is not None: # find the toplevel Gtk.Window
        parent = parent.get_toplevel()
        if not parent.is_toplevel():
            parent = None

    if not is_string_like(msg):
        msg = ','.join(map(str,msg))

    dialog = Gtk.MessageDialog(
        parent         = parent,
        type           = Gtk.MessageType.ERROR,
        buttons        = Gtk.ButtonsType.OK,
        message_format = msg)
    dialog.run()
    dialog.destroy()