python中的嵌套类（内部类调用外部类中的方法函数）

class DiagramFactory: @classmethod def make_diagram(Class, width, height): return Class.Diagram(width, height) @classmethod def make_rectangle(Class, x, y, width, height, fill="white", stroke="black"): return Class.Rectangle(x, y, width, height, fill, stroke) @classmethod def make_text(Class, x, y, text, fontsize=12): return Class.Text(x, y, text, fontsize) BLANK = " " CORNER = "+" HORIZONTAL = "-" VERTICAL = "|" class Diagram: def __init__(self, width, height): self.superclass = DiagramFactory() self.width = width self.height = height self.diagram = DiagramFactory._create_rectangle(self.superclass,self.width, self.height, DiagramFactory.BLANK) def add(self, component): for y, row in enumerate(component.rows): for x, char in enumerate(row): self.diagram[y + component.y][x + component.x] = char def save(self, filenameOrFile): file = (None if isinstance(filenameOrFile, str) else filenameOrFile) try: if file is None: file = open(filenameOrFile, "w") for row in self.diagram: print >>file, "".join(row) finally: if isinstance(filenameOrFile, str) and file is not None: file.close() class Rectangle: def __init__(self, x, y, width, height, fill, stroke): self.superclass = DiagramFactory() self.x = x self.y = y self.rows = DiagramFactory._create_rectangle(self.superclass, width, height, DiagramFactory.BLANK if fill == "white" else "%") class Text: def __init__(self, x, y, text, fontsize): self.x = x self.y = y self.rows = [list(text)] def _create_rectangle(self, width, height, fill): rows = [[fill for _ in range(width)] for _ in range(height)] for x in range(1, width - 1): rows[0][x] = DiagramFactory.HORIZONTAL rows[height - 1][x] = DiagramFactory.HORIZONTAL for y in range(1, height - 1): rows[y][0] = DiagramFactory.VERTICAL rows[y][width - 1] = DiagramFactory.VERTICAL for y, x in ((0, 0), (0, width - 1), (height - 1, 0), (height - 1, width -1)): rows[y][x] = DiagramFactory.CORNER return rows