Exemplo n.º 1
0
    def build_gui(self, container):
        """
        This is responsible for building the viewer's UI.  It should
        place the UI in `container`.
        """
        vbox = Widgets.VBox()
        vbox.set_border_width(2)
        vbox.set_spacing(1)

        w = Viewers.GingaViewerWidget(viewer=self)
        vbox.add_widget(w, stretch=1)

        # set up to capture cursor movement for reading out coordinates

        # coordinates reported in base 1 or 0?
        self.pixel_base = 1.0

        self.readout = Widgets.Label("")
        vbox.add_widget(self.readout, stretch=0)

        #self.set_callback('none-move', self.motion_cb)
        self.set_callback('cursor-changed', self.motion_cb)

        # need to put this in an hbox with an expanding label or the
        # browser wants to resize the canvas, distorting it
        hbox = Widgets.HBox()
        hbox.add_widget(vbox, stretch=0)
        hbox.add_widget(Widgets.Label(''), stretch=1)

        container.set_widget(hbox)
Exemplo n.º 2
0
    def build_gui(self, container):
        """
        This is responsible for building the viewer's UI.  It should
        place the UI in `container`.  Override this to make a custom
        UI.
        """
        vbox = Widgets.VBox()
        vbox.set_border_width(0)

        w = Viewers.GingaViewerWidget(viewer=self)
        vbox.add_widget(w, stretch=1)

        # need to put this in an hbox with an expanding label or the
        # browser wants to resize the canvas, distorting it
        hbox = Widgets.HBox()
        hbox.add_widget(vbox, stretch=0)
        hbox.add_widget(Widgets.Label(''), stretch=1)

        container.set_widget(hbox)
Exemplo n.º 3
0
    def __init__(self, logger, window, viewer_class=None):
        if viewer_class is None:
            viewer_class = EnhancedCanvasView
        self.logger = logger
        self.url = window.url
        self.drawcolors = colors.get_colors()
        self.dc = get_canvas_types()

        self.top = window
        self.top.add_callback('close', self.closed)

        vbox = Widgets.VBox()
        vbox.set_border_width(2)
        vbox.set_spacing(1)

        fi = viewer_class(logger)
        fi.url = self.url
        fi.enable_autocuts('on')
        fi.set_autocut_params('zscale')
        fi.enable_autozoom('on')
        fi.set_zoom_algorithm('rate')
        fi.set_zoomrate(1.4)
        fi.show_pan_mark(True)
        fi.set_callback('drag-drop', self.drop_file)
        fi.set_callback('none-move', self.motion)
        fi.set_bg(0.2, 0.2, 0.2)
        fi.ui_setActive(True)
        self.fitsimage = fi

        bd = fi.get_bindings()
        bd.enable_all(True)

        # so trackpad scrolling can be adjusted
        settings = bd.get_settings()
        settings.set(scroll_zoom_direct_scale=True)

        # so trackpad scrolling can be adjusted
        settings = bd.get_settings()
        settings.set(scroll_zoom_direct_scale=True,
                     scroll_zoom_acceleration=0.07)

        # canvas that we will draw on
        canvas = self.dc.DrawingCanvas()
        #canvas.enable_draw(True)
        #canvas.enable_edit(True)
        #canvas.set_drawtype('rectangle', color='lightblue')
        canvas.setSurface(fi)
        self.canvas = canvas
        # add canvas to view
        private_canvas = fi.get_canvas()
        private_canvas.add(canvas)
        canvas.ui_setActive(True)
        #canvas.register_for_cursor_drawing(fi)
        fi.set_canvas(canvas)
        ## self.drawtypes = canvas.get_drawtypes()
        ## self.drawtypes.sort()

        # add a color bar
        private_canvas.add(self.dc.ColorBar(side='bottom', offset=10))

        # add little mode indicator that shows modal states in
        # the corner
        private_canvas.add(self.dc.ModeIndicator(corner='ur', fontsize=14))
        # little hack necessary to get correct operation of the mode indicator
        # in all circumstances
        bm = fi.get_bindmap()
        bm.add_callback('mode-set', lambda *args: fi.redraw(whence=3))

        fi.set_desired_size(512, 512)
        w = Viewers.GingaViewerWidget(viewer=fi)
        vbox.add_widget(w, stretch=1)

        self.readout = Widgets.Label("")
        vbox.add_widget(self.readout, stretch=0)

        hbox = Widgets.HBox()
        hbox.add_widget(Widgets.Label('Zoom sensitivity: '))
        slider = Widgets.Slider(orientation='horizontal', dtype=float)
        slider.add_callback('value-changed',
                            lambda w, val: self.adjust_scrolling_accel_cb(val))
        slider.set_limits(0.0, 12.0, 0.005)
        slider.set_value(8.0)
        hbox.add_widget(slider, stretch=1)

        hbox.add_widget(Widgets.Label(''), stretch=1)
        vbox.add_widget(hbox, stretch=0)

        # need to put this in an hbox with an expanding label or the
        # browser wants to resize the canvas, distorting it
        hbox = Widgets.HBox()
        hbox.add_widget(vbox, stretch=0)
        hbox.add_widget(Widgets.Label(''), stretch=1)

        self.top.set_widget(hbox)
Exemplo n.º 4
0
    def __init__(self, logger, window):
        self.logger = logger
        self.drawcolors = colors.get_colors()
        self.dc = get_canvas_types()

        self.top = window
        self.top.add_callback('close', self.closed)

        vbox = Widgets.VBox()
        vbox.set_border_width(2)
        vbox.set_spacing(1)

        fi = EnhancedCanvasView(logger)
        fi.enable_autocuts('on')
        fi.set_autocut_params('zscale')
        fi.enable_autozoom('on')
        fi.set_zoom_algorithm('rate')
        fi.set_zoomrate(1.4)
        fi.show_pan_mark(True)
        fi.set_callback('drag-drop', self.drop_file)
        fi.set_callback('none-move', self.motion)
        fi.set_bg(0.2, 0.2, 0.2)
        fi.ui_setActive(True)
        self.fitsimage = fi

        bd = fi.get_bindings()
        bd.enable_all(True)

        # canvas that we will draw on
        canvas = self.dc.DrawingCanvas()
        canvas.enable_draw(True)
        canvas.enable_edit(True)
        canvas.set_drawtype('rectangle', color='lightblue')
        canvas.setSurface(fi)
        self.canvas = canvas
        # add canvas to view
        private_canvas = fi.get_canvas()
        private_canvas.add(canvas)
        canvas.ui_setActive(True)
        canvas.register_for_cursor_drawing(fi)
        fi.set_canvas(canvas)
        ## self.drawtypes = canvas.get_drawtypes()
        ## self.drawtypes.sort()

        # add a color bar
        private_canvas.add(self.dc.ColorBar(side='bottom', offset=10))

        # add little mode indicator that shows modal states in
        # the corner
        private_canvas.add(self.dc.ModeIndicator(corner='ur', fontsize=14))
        # little hack necessary to get correct operation of the mode indicator
        # in all circumstances
        bm = fi.get_bindmap()
        bm.add_callback('mode-set', lambda *args: fi.redraw(whence=3))

        fi.set_desired_size(512, 512)
        w = Viewers.GingaViewerWidget(viewer=fi)
        vbox.add_widget(w, stretch=1)

        self.readout = Widgets.Label("")
        vbox.add_widget(self.readout, stretch=0)

        hbox = Widgets.HBox()
        btn3 = Widgets.CheckBox("I'm using a trackpad")
        btn3.add_callback('activated', lambda w, tf: self.use_trackpad_cb(tf))
        hbox.add_widget(btn3)

        hbox.add_widget(Widgets.Label(''), stretch=1)
        vbox.add_widget(hbox, stretch=0)

        self.top.set_widget(vbox)
Exemplo n.º 5
0
    def __init__(self, logger, window):
        self.logger = logger
        self.drawcolors = colors.get_colors()
        self.dc = get_canvas_types()

        self.top = window
        self.top.add_callback('close', self.closed)

        vbox = Widgets.VBox()
        vbox.set_border_width(2)
        vbox.set_spacing(1)

        fi = Viewers.CanvasView(logger)
        fi.enable_autocuts('on')
        fi.set_autocut_params('zscale')
        fi.enable_autozoom('on')
        fi.set_zoom_algorithm('rate')
        fi.set_zoomrate(1.4)
        fi.show_pan_mark(True)
        fi.set_callback('drag-drop', self.drop_file)
        fi.set_callback('none-move', self.motion)
        fi.set_bg(0.2, 0.2, 0.2)
        fi.ui_setActive(True)
        self.fitsimage = fi

        bd = fi.get_bindings()
        bd.enable_all(True)

        # so trackpad scrolling can be adjusted
        settings = bd.get_settings()
        settings.set(scroll_zoom_direct_scale=True,
                     scroll_zoom_acceleration=0.07)

        # canvas that we will draw on
        canvas = self.dc.DrawingCanvas()
        canvas.enable_draw(True)
        canvas.enable_edit(True)
        canvas.set_drawtype('rectangle', color='lightblue')
        canvas.setSurface(fi)
        self.canvas = canvas
        # add canvas to view
        private_canvas = fi.get_canvas()
        private_canvas.add(canvas)
        canvas.ui_setActive(True)
        canvas.register_for_cursor_drawing(fi)
        self.drawtypes = canvas.get_drawtypes()
        self.drawtypes.sort()

        # add a color bar
        fi.show_color_bar(True)

        # add little mode indicator that shows keyboard modal states
        fi.show_mode_indicator(True, corner='ur')

        fi.set_desired_size(512, 512)
        w = Viewers.GingaViewerWidget(viewer=fi)
        vbox.add_widget(w, stretch=1)

        self.readout = Widgets.Label("")
        vbox.add_widget(self.readout, stretch=0)

        hbox = Widgets.HBox()
        hbox.set_border_width(2)

        wdrawtype = Widgets.ComboBox()
        for name in self.drawtypes:
            wdrawtype.append_text(name)
        index = self.drawtypes.index('rectangle')
        wdrawtype.set_index(index)
        wdrawtype.add_callback('activated',
                               lambda w, idx: self.set_drawparams())
        self.wdrawtype = wdrawtype

        wdrawcolor = Widgets.ComboBox()
        for name in self.drawcolors:
            wdrawcolor.append_text(name)
        index = self.drawcolors.index('lightblue')
        wdrawcolor.set_index(index)
        wdrawcolor.add_callback('activated',
                                lambda w, idx: self.set_drawparams())
        self.wdrawcolor = wdrawcolor

        wfill = Widgets.CheckBox("Fill")
        wfill.add_callback('activated', lambda w, tf: self.set_drawparams())
        self.wfill = wfill

        walpha = Widgets.SpinBox(dtype=float)
        walpha.set_limits(0.0, 1.0, incr_value=0.1)
        walpha.set_value(1.0)
        walpha.set_decimals(2)
        walpha.add_callback('value-changed',
                            lambda w, val: self.set_drawparams())
        self.walpha = walpha

        wclear = Widgets.Button("Clear Canvas")
        wclear.add_callback('activated', lambda w: self.clear_canvas())
        ## wopen = Widgets.Button("Open File")
        ## wopen.add_callback('activated', lambda w: self.open_file())
        ## wquit = Widgets.Button("Quit")
        ## wquit.add_callback('activated', lambda w: self.quit())

        hbox.add_widget(Widgets.Label(''), stretch=1)
        for w in (wdrawtype, wdrawcolor, wfill, Widgets.Label('Alpha:'),
                  walpha, wclear):
            hbox.add_widget(w, stretch=0)

        vbox.add_widget(hbox, stretch=0)

        mode = self.canvas.get_draw_mode()
        hbox = Widgets.HBox()
        btn1 = Widgets.RadioButton("Draw")
        btn1.set_state(mode == 'draw')
        btn1.add_callback('activated',
                          lambda w, val: self.set_mode_cb('draw', val))
        btn1.set_tooltip("Choose this to draw on the canvas")
        hbox.add_widget(btn1)

        btn2 = Widgets.RadioButton("Edit", group=btn1)
        btn2.set_state(mode == 'edit')
        btn2.add_callback('activated',
                          lambda w, val: self.set_mode_cb('edit', val))
        btn2.set_tooltip("Choose this to edit things on the canvas")
        hbox.add_widget(btn2)

        hbox.add_widget(Widgets.Label('Zoom sensitivity: '))
        slider = Widgets.Slider(orientation='horizontal', dtype=float)
        slider.add_callback('value-changed',
                            lambda w, val: self.adjust_scrolling_accel_cb(val))
        slider.set_limits(0.0, 12.0, 0.005)
        slider.set_value(8.0)
        hbox.add_widget(slider, stretch=1)

        # hbox.add_widget(Widgets.Label(''), stretch=1)
        vbox.add_widget(hbox, stretch=0)

        # need to put this in an hbox with an expanding label or the
        # browser wants to resize the canvas
        hbox = Widgets.HBox()
        hbox.add_widget(vbox, stretch=0)
        hbox.add_widget(Widgets.Label(''), stretch=1)

        self.top.set_widget(hbox)
Exemplo n.º 6
0
    def __init__(self, logger, window):
        self.logger = logger
        self.drawcolors = colors.get_colors()
        self.dc = get_canvas_types()

        self.top = window
        self.top.add_callback('close', self.closed)

        vbox = Widgets.VBox()
        vbox.set_border_width(2)
        vbox.set_spacing(1)

        fi = Viewers.CanvasView(logger)
        fi.enable_autocuts('on')
        fi.set_autocut_params('zscale')
        fi.enable_autozoom('on')
        fi.set_zoom_algorithm('rate')
        fi.set_zoomrate(1.4)
        fi.show_pan_mark(True)
        fi.set_callback('drag-drop', self.drop_file)
        fi.set_callback('none-move', self.motion)
        fi.set_bg(0.2, 0.2, 0.2)
        fi.ui_setActive(True)
        self.fitsimage = fi

        bd = fi.get_bindings()
        bd.enable_all(True)

        # canvas that we will draw on
        canvas = self.dc.DrawingCanvas()
        canvas.enable_draw(True)
        canvas.enable_edit(True)
        canvas.set_drawtype('rectangle', color='lightblue')
        canvas.setSurface(fi)
        self.canvas = canvas
        # add canvas to view
        private_canvas = fi.get_canvas()
        private_canvas.add(canvas)
        canvas.ui_setActive(True)
        canvas.register_for_cursor_drawing(fi)
        self.drawtypes = canvas.get_drawtypes()
        self.drawtypes.sort()

        # add a color bar
        private_canvas.add(self.dc.ColorBar(side='bottom', offset=10))

        # add little mode indicator that shows modal states in
        # the corner
        private_canvas.add(self.dc.ModeIndicator(corner='ur', fontsize=14))
        # little hack necessary to get correct operation of the mode indicator
        # in all circumstances
        bm = fi.get_bindmap()
        bm.add_callback('mode-set', lambda *args: fi.redraw(whence=3))

        fi.set_desired_size(512, 512)
        w = Viewers.GingaViewerWidget(viewer=fi)
        vbox.add_widget(w, stretch=1)

        self.readout = Widgets.Label("")
        vbox.add_widget(self.readout, stretch=0)

        hbox = Widgets.HBox()
        hbox.set_border_width(2)

        wdrawtype = Widgets.ComboBox()
        for name in self.drawtypes:
            wdrawtype.append_text(name)
        index = self.drawtypes.index('rectangle')
        wdrawtype.set_index(index)
        wdrawtype.add_callback('activated',
                               lambda w, idx: self.set_drawparams())
        self.wdrawtype = wdrawtype

        wdrawcolor = Widgets.ComboBox()
        for name in self.drawcolors:
            wdrawcolor.append_text(name)
        index = self.drawcolors.index('lightblue')
        wdrawcolor.set_index(index)
        wdrawcolor.add_callback('activated',
                                lambda w, idx: self.set_drawparams())
        self.wdrawcolor = wdrawcolor

        wfill = Widgets.CheckBox("Fill")
        wfill.add_callback('activated', lambda w, tf: self.set_drawparams())
        self.wfill = wfill

        walpha = Widgets.SpinBox(dtype=float)
        walpha.set_limits(0.0, 1.0, incr_value=0.1)
        walpha.set_value(1.0)
        walpha.set_decimals(2)
        walpha.add_callback('value-changed',
                            lambda w, val: self.set_drawparams())
        self.walpha = walpha

        wclear = Widgets.Button("Clear Canvas")
        wclear.add_callback('activated', lambda w: self.clear_canvas())
        ## wopen = Widgets.Button("Open File")
        ## wopen.add_callback('activated', lambda w: self.open_file())
        ## wquit = Widgets.Button("Quit")
        ## wquit.add_callback('activated', lambda w: self.quit())

        hbox.add_widget(Widgets.Label(''), stretch=1)
        for w in (wdrawtype, wdrawcolor, wfill, Widgets.Label('Alpha:'),
                  walpha, wclear):
            hbox.add_widget(w, stretch=0)

        vbox.add_widget(hbox, stretch=0)

        mode = self.canvas.get_draw_mode()
        hbox = Widgets.HBox()
        btn1 = Widgets.RadioButton("Draw")
        btn1.set_state(mode == 'draw')
        btn1.add_callback('activated',
                          lambda w, val: self.set_mode_cb('draw', val))
        btn1.set_tooltip("Choose this to draw on the canvas")
        hbox.add_widget(btn1)

        btn2 = Widgets.RadioButton("Edit", group=btn1)
        btn2.set_state(mode == 'edit')
        btn2.add_callback('activated',
                          lambda w, val: self.set_mode_cb('edit', val))
        btn2.set_tooltip("Choose this to edit things on the canvas")
        hbox.add_widget(btn2)

        btn3 = Widgets.CheckBox("I'm using a trackpad")
        btn3.add_callback('activated', lambda w, tf: self.use_trackpad_cb(tf))
        hbox.add_widget(btn3)

        hbox.add_widget(Widgets.Label(''), stretch=1)
        vbox.add_widget(hbox, stretch=0)

        self.top.set_widget(vbox)
Exemplo n.º 7
0
    def build_gui(self, container):
        """
        Building the GUI to be displayed in an HTML5 canvas.
        Tested and working in Mozilla Firefox and Google Chrome web browsers.

        :param container: ginga.web.pgw.Widgets.TopLevel object
        """
        bindings = self.get_bindings()
        bindings.enable_all(True)

        # keyboard mode indicator, upper right corner
        self.show_mode_indicator(True, corner='ur')

        viewer_vbox = Widgets.VBox()  # box containing the viewer
        viewer_vbox.set_border_width(2)
        viewer_vbox.set_spacing(1)
        viewer_widget = Viewers.GingaViewerWidget(viewer=self)
        viewer_vbox.add_widget(viewer_widget, stretch=1)
        viewer_vbox.add_widget(
            self.readout,
            stretch=0)  # text directly below the viewer for coordinate display

        self.set_callback('cursor-changed', self.motion_cb)

        healpix_set = Widgets.TextEntrySet()
        healpix_set.add_callback('activated',
                                 lambda x: self.set_healpix(event=x))
        healpix_set.set_length(6)

        candidate_override = Widgets.TextEntrySet()
        candidate_override.add_callback('activated',
                                        lambda x: self.override_set(event=x))
        candidate_override.set_length(10)

        astfile = Widgets.TextEntry(editable=True)
        astfile.add_callback('activated', lambda x: self.load_astfile(event=x))

        catalog = Widgets.TextEntrySet(text='17AQ03')
        catalog.add_callback('activated', lambda x: self.set_qrun_id(x))
        catalog.set_length(5)

        self.accept.add_callback('activated', lambda x: self.accept_reject())
        self.reject.add_callback('activated',
                                 lambda x: self.accept_reject(rejected=True))
        self.load_json.add_callback('activated',
                                    lambda x: self.load_candidates())
        self.next_set.add_callback('activated', lambda x: self.next())
        self.previous_set.add_callback('activated', lambda x: self.previous())
        self.clear_button.add_callback('activated',
                                       lambda x: self.clear_viewer())
        self.reload_button.add_callback('activated',
                                        lambda x: self.reload_candidates())

        # accept/reject/next buttons
        buttons_hbox = Widgets.HBox()
        buttons_hbox.add_widget(self.previous_set)
        buttons_hbox.add_widget(self.accept)
        buttons_hbox.add_widget(self.reject)
        buttons_hbox.add_widget(self.next_set)
        buttons_hbox.add_widget(self.load_json)
        buttons_hbox.add_widget(self.reload_button)
        buttons_hbox.add_widget(self.clear_button)
        self.load_json.set_enabled(False)
        buttons_hbox.set_spacing(3)

        # catalog directory text box
        catalog_box = Widgets.HBox()
        catalog_label = Widgets.Label(text="Set QRUNID:", style='color:red')
        catalog_box.add_widget(catalog_label)
        catalog_box.add_widget(catalog)
        catalog_box.set_margins(15, 0, 10, 0)  # top, right, bottom, left

        candidates_hbox = Widgets.HBox()
        candidate_label = Widgets.Label(
            text="(Optional) Enter candidate set (HEALPIX): ")
        candidates_hbox.add_widget(candidate_label)
        candidates_hbox.add_widget(healpix_set)
        candidates_hbox.set_margins(15, 0, 15, 0)  # top, right, bottom, left

        override_hbox = Widgets.HBox()
        override_label = Widgets.Label(
            text="(Optional) Override provisional name: ")
        override_hbox.add_widget(override_label)
        override_hbox.add_widget(candidate_override)
        override_hbox.set_margins(0, 0, 15, 0)  # top, right, bottom, left

        astfile_hbox = Widgets.HBox()
        astfile_hbox_label = Widgets.Label(text="Paste AST file here:")
        astfile_hbox.add_widget(astfile_hbox_label)
        astfile_hbox.add_widget(astfile)

        # button and text entry vbox
        buttons_vbox = Widgets.VBox()
        buttons_vbox.add_widget(buttons_hbox)
        buttons_vbox.add_widget(catalog_box)
        buttons_vbox.add_widget(candidates_hbox)
        buttons_vbox.add_widget(override_hbox)
        buttons_vbox.add_widget(astfile_hbox)

        viewer_vbox.add_widget(buttons_vbox)  # add buttons below the viewer

        viewer_header_hbox = Widgets.HBox(
        )  # box containing the viewer/buttons and rightmost text area
        viewer_header_hbox.add_widget(viewer_vbox)
        viewer_header_hbox.add_widget(Widgets.Label(''))
        hbox = Widgets.HBox()
        hbox.add_widget(self.header_box)
        hbox.add_widget(self.legend)
        viewer_header_hbox.add_widget(hbox)

        full_vbox = Widgets.VBox()  # vbox container for all elements
        full_vbox.add_widget(viewer_header_hbox)

        full_vbox.add_widget(self.console_box)
        self.console_box.set_text('Logging output:\n')
        self.header_box.set_text("Header:")

        container.set_widget(full_vbox)
        container.set_widget(self.warning)
        container.set_widget(self.yes_button)
        container.set_widget(self.no_button)
        self.yes_button.set_enabled(False)
        self.no_button.set_enabled(False)
        self.buttons_off()
Exemplo n.º 8
0
    def __init__(self, logger, window, viewer_class=None, width=512, height=512):
        if viewer_class is None:
            viewer_class = EnhancedCanvasView
        self.logger = logger
        self.url = window.url
        self.dc = get_canvas_types()
        self.pixel_base = 1.0

        self.top = window
        self.top.add_callback('close', self.closed)

        vbox = Widgets.VBox()
        vbox.set_border_width(2)
        vbox.set_spacing(1)

        # load binding preferences if available
        cfgfile = os.path.join(ginga_home, "ipg_bindings.cfg")
        bindprefs = SettingGroup(name='bindings', logger=logger,
                                 preffile=cfgfile)
        bindprefs.load(onError='silent')

        bd = ImageViewBindings(logger, settings=bindprefs)

        fi = viewer_class(logger, bindings=bd)
        fi.url = self.url
        fi.enable_autocuts('on')
        fi.set_autocut_params('zscale')
        fi.set_zoom_algorithm('rate')
        fi.set_zoomrate(1.1)
        fi.enable_autozoom('on')
        #fi.set_callback('drag-drop', self.drop_file)
        fi.set_callback('none-move', self.motion)
        fi.set_bg(0.2, 0.2, 0.2)
        fi.ui_setActive(True)
        self.fitsimage = fi
        fi.ipg_parent = self

        bd = fi.get_bindings()
        bd.enable_all(True)

        # canvas that we will draw on
        canvas = self.dc.DrawingCanvas()
        canvas.set_surface(fi)
        self.canvas = canvas
        # add canvas to view
        private_canvas = fi.get_canvas()
        private_canvas.add(canvas)
        canvas.ui_setActive(True)
        fi.set_canvas(canvas)

        fi.set_desired_size(width, height)
        # force allocation of a surface--may be resized later
        fi.configure_surface(width, height)

        # add little mode indicator that shows modal states in
        # the corner
        fi.show_mode_indicator(True)

        w = Viewers.GingaViewerWidget(viewer=fi)
        vbox.add_widget(w, stretch=1)

        self.readout = Widgets.Label("")
        vbox.add_widget(self.readout, stretch=0)

        hbox = Widgets.HBox()
        hbox.add_widget(Widgets.Label('Zoom sensitivity: '))
        slider = Widgets.Slider(orientation='horizontal', dtype=float)
        slider.add_callback('value-changed',
                            lambda w, val: self.adjust_scrolling_accel_cb(val))
        slider.set_limits(1.0, 9.5, 0.1)
        val = 4.0
        slider.set_value(val)
        self.adjust_scrolling_accel_cb(val)
        hbox.add_widget(slider, stretch=1)

        hbox.add_widget(Widgets.Label(''), stretch=1)
        vbox.add_widget(hbox, stretch=0)

        # need to put this in an hbox with an expanding label or the
        # browser wants to resize the canvas, distorting it
        hbox = Widgets.HBox()
        hbox.add_widget(vbox, stretch=0)
        hbox.add_widget(Widgets.Label(''), stretch=1)

        self.top.set_widget(hbox)