如何让tkinter canvas动态调整窗口宽度？

Question

我需要在tkinter中获取一个画布,将其宽度设置为窗口的宽度,然后在用户使窗口变小/变大时动态地重新调整画布大小.

有没有办法(轻松)这样做？

Answer 1

我想我会添加一些额外的代码来扩展@ fredtantini的答案,因为它没有处理如何更新绘制的小部件的形状Canvas.

为此,您需要使用该scale方法并标记所有小部件.下面是一个完整的例子.

from Tkinter import *

# a subclass of Canvas for dealing with resizing of windows
class ResizingCanvas(Canvas):
    def __init__(self,parent,**kwargs):
        Canvas.__init__(self,parent,**kwargs)
        self.bind("<Configure>", self.on_resize)
        self.height = self.winfo_reqheight()
        self.width = self.winfo_reqwidth()

    def on_resize(self,event):
        # determine the ratio of old width/height to new width/height
        wscale = float(event.width)/self.width
        hscale = float(event.height)/self.height
        self.width = event.width
        self.height = event.height
        # resize the canvas 
        self.config(width=self.width, height=self.height)
        # rescale all the objects tagged with the "all" tag
        self.scale("all",0,0,wscale,hscale)

def main():
    root = Tk()
    myframe = Frame(root)
    myframe.pack(fill=BOTH, expand=YES)
    mycanvas = ResizingCanvas(myframe,width=850, height=400, bg="red", highlightthickness=0)
    mycanvas.pack(fill=BOTH, expand=YES)

    # add some widgets to the canvas
    mycanvas.create_line(0, 0, 200, 100)
    mycanvas.create_line(0, 100, 200, 0, fill="red", dash=(4, 4))
    mycanvas.create_rectangle(50, 25, 150, 75, fill="blue")

    # tag all of the drawn widgets
    mycanvas.addtag_all("all")
    root.mainloop()

if __name__ == "__main__":
    main()

Answer 2

您可以使用.pack几何管理器:

self.c=Canvas(…)
self.c.pack(fill="both", expand=True)

应该做的伎俩.如果画布位于框架内,请对框架执行相同操作:

self.r = root
self.f = Frame(self.r)
self.f.pack(fill="both", expand=True)
self.c = Canvas(…)
self.c.pack(fill="both", expand=True)

有关更多信息,请参阅effbot.

编辑:如果您不想要"全尺寸"画布,可以将画布绑定到一个函数:

self.c.bind('<Configure>', self.resize)

def resize(self, event):
    w,h = event.width-100, event.height-100
    self.c.config(width=w, height=h)

再次看到effbot的事件和绑定