Question

我正在尝试创建一个简单的绘图程序，其中的按钮通过删除其上的所有形状来清除画布，但是我尝试使用内置到tkinter中的delete（）命令，但是当我尝试运行它时说删除没有定义。我做错了什么？

from Tkinter import *
import Tkinter
root = Tk()

class PaintBox( Frame ):
    def __init__( self ):
        Frame.__init__( self )
        self.pack( expand = YES, fill = BOTH )
        self.master.title( "Color Draw v0.2.63.23 open closed beta (Still in Alpha) greenlight edition" )
        self.master.geometry( "600x600" )

        self.message = Label( self, text = "Drag the mouse SLOWLY to draw" )
        self.message.pack( side = TOP )

        self.myCanvas = Canvas( self )
        self.myCanvas.pack( expand = YES, fill = BOTH )
        self.bd = (2)

        self.myCanvas.bind( "<B1-Motion>", self.paint )

    def paint( self, event ):
        x1, y1 = ( event.x - 4 ), ( event.y - 4 )
        x2, y2 = ( event.x + 4 ), ( event.y + 4 )
        self.myCanvas.create_rectangle( x1, y1, x2, y2, fill = "black", tags="box")

    button = Button(root, text = "Clear", command = delete(box))
    button.grid(row = 1, column = 0)

PaintBox().mainloop()

这是完整的追溯@mgilson：

    ERROR: execution aborted

In [2]: %run C:/Users/en58522/Downloads/paintcolor.txt---------------------------------------------------------------------------
NameError                                 Traceback (most recent call last)
C:\Program Files\Enthought\Canopy\App\appdata\canopy-1.4.1.1975.win-x86_64\lib\site-packages\IPython\utils\py3compat.pyc in execfile(fname, glob, loc)
    195             else:
    196                 filename = fname
--> 197             exec compile(scripttext, filename, 'exec') in glob, loc
    198     else:
    199         def execfile(fname, *where):

C:\Users\en58522\Downloads\paintcolor.txt in <module>()
      3 root = Tk()
      4 
----> 5 class PaintBox( Frame ):
      6     def __init__( self ):
      7         Frame.__init__( self )

C:\Users\en58522\Downloads\paintcolor.txt in PaintBox()
     24         self.myCanvas.create_rectangle( x1, y1, x2, y2, fill = "black", tags="box")
     25 
---> 26     button = Button(root, text = "Clear", command = delete(box))
     27     button.grid(row = 1, column = 0)
     28 

NameError: name 'delete' is not defined

Answer 1

以下是一些可以帮助您入门的工作代码：

from Tkinter import *
import Tkinter
root = Tk()

class PaintBox( Frame ):
    def __init__( self, root ):
        Frame.__init__( self, root )
        self.pack( expand = YES, fill = BOTH )
        self.master.title( "Color Draw v0.2.63.23 open closed beta (Still in Alpha) greenlight edition" )
        self.master.geometry( "600x600" )

        self.message = Label( self, text = "Drag the mouse SLOWLY to draw" )
        self.message.pack( side = TOP )

        self.myCanvas = Canvas( self )
        self.myCanvas.pack( expand = YES, fill = BOTH )
        self.bd = (2)

        self.myCanvas.bind( "<B1-Motion>", self.paint )
        button = Button(root, text = "Clear", command = self.delete)
        button.pack()


    def paint( self, event ):
        x1, y1 = ( event.x - 4 ), ( event.y - 4 )
        x2, y2 = ( event.x + 4 ), ( event.y + 4 )
        self.myCanvas.create_rectangle( x1, y1, x2, y2, fill = "black", tags="box")


    def delete(self):
        items = self.myCanvas.find_all()
        for item in items:
            self.myCanvas.delete(item)

PaintBox(root).mainloop()

我尽可能地保持原始代码的真实性。

要注意的一些事情......

我.pack按钮，因为在同一个小部件中使用.grid和.pack不起作用。
我定义了一个delete函数，用于清除您输入的框的网格。我在班级__init__中定义了它。
command = ...应该是一个功能。您的原始代码尝试在command = ...位中进行函数调用。这是一个常见的错误，导致在创建按钮时执行该功能，然后再也不会执行。我使用了绑定方法，因为绑定方法会隐式传递self。

Tkinter名称＆＃34;删除＆＃34;没有定义的

1 个答案: