builds basic GUI panel and popup menu

def BuildPanel(self):
        """ builds basic GUI panel and popup menu"""
        figsize = (1.0*self.size[0]/self.dpi, 1.0*self.size[1]/self.dpi)
        self.fig   = Figure(figsize, dpi=self.dpi)
        self.axes  = self.fig.add_axes([0.0, 0.0, 1.0, 1.0])

        self.canvas = FigureCanvasWxAgg(self, -1, self.fig)
        self.fig.set_facecolor('#FFFFFD')

        self.conf.axes  = self.axes
        self.conf.fig   = self.fig
        self.conf.canvas= self.canvas

        # self.canvas.SetCursor(wx.StockCursor(wx.CURSOR_ARROW))
        # This way of adding to sizer allows resizing
        sizer = wx.BoxSizer(wx.HORIZONTAL)
        sizer.Add(self.canvas, 1, wx.ALL|wx.GROW)
        self.SetSizer(sizer)
        self.Fit()
        self.addCanvasEvents()