drt.py 文件源码

def __init__(self, drs, size_canvas=True, canvas=None):
        """
        :param drs: ``DrtExpression``, The DRS to be drawn
        :param size_canvas: bool, True if the canvas size should be the exact size of the DRS
        :param canvas: ``Canvas`` The canvas on which to draw the DRS.  If none is given, create a new canvas.
        """
        master = None
        if not canvas:
            master = Tk()
            master.title("DRT")

            font = Font(family='helvetica', size=12)

            if size_canvas:
                canvas = Canvas(master, width=0, height=0)
                canvas.font = font
                self.canvas = canvas
                (right, bottom) = self._visit(drs, self.OUTERSPACE, self.TOPSPACE)

                width = max(right+self.OUTERSPACE, 100)
                height = bottom+self.OUTERSPACE
                canvas = Canvas(master, width=width, height=height)#, bg='white')
            else:
                canvas = Canvas(master, width=300, height=300)

            canvas.pack()
            canvas.font = font

        self.canvas = canvas
        self.drs = drs
        self.master = master