TkInter:绘制错误的位置 [英] TkInter: drawing on wrong positions

问题描述

我在 Canvas 上加载了一张图片.这是一张大图片，所以我需要垂直和水平滚动才能看到它.我还让用户在图像上使用鼠标指针绘制随机曲线/线条.

I load a picture on the Canvas. It is a large picture so I need to scroll vertically and horizontally to be able to see it. I also let the user to drawn random curves/lines using the mouse pointer on the image.

一切都很好，除了当我水平或垂直滚动​​然后我尝试绘制时，我看到曲线不是在鼠标指向的地方绘制的，而是在其他地方绘制的.我该如何解决这个问题?

Everything is ok except that when I scroll horizontally or vertically then I try to draw I see the curves are not drawn where the mouse points to but in an other place. How can I resolve this problem ?

这是我的代码:

import PIL.Image
import PIL.ImageTk
from Tkinter import *    
import numpy as np
import cv2   

class ExampleApp(Frame):
   def __init__(self,master):
        Frame.__init__(self,master=None)
        self.x = self.y = 0
        self.imcv=None
        self.canvas=Canvas(self,width=600,height=600)
        self.b1="up"
        self.liste=[]
        self.xold=None
        self.yold=None

   def dessiner(self):
       # Load the imge and allow user to scroll it if it is large.
       self.canvas.bind("<Motion>",self.motion)
       self.canvas.bind("<ButtonPress-1>",self.b1down)
       self.canvas.bind("<ButtonRelease-1>",self.b1up)
       self.sbarv=Scrollbar(self,orient=VERTICAL)
       self.sbarh=Scrollbar(self,orient=HORIZONTAL)
       self.sbarv.config(command=self.canvas.yview)
       self.sbarh.config(command=self.canvas.xview)

       self.canvas.config(yscrollcommand=self.sbarv.set)
       self.canvas.config(xscrollcommand=self.sbarh.set)

       self.canvas.grid(row=0,column=0,sticky=N+S+E+W)
       self.sbarv.grid(row=0,column=1,stick=N+S)
       self.sbarh.grid(row=1,column=0,sticky=E+W)
       self.im = PIL.Image.open("image.jpg")
       self.widt,self.heigt=self.im.size
       self.canvas.config(scrollregion=(0,0,self.widt,self.heigt))
       self.tk_im = PIL.ImageTk.PhotoImage(self.im)
       self.canvas.create_image(0,0,anchor="nw",image=self.tk_im)   


   def b1up(self,event):
       self.b1="up"
   def b1down(self,event):
       self.b1="down"
       self.xold=None
       self.yold=None
       self.liste.append((self.xold,self.yold))
   def motion(self,event):
       if self.b1=="down":
           if self.xold is not None and self.yold is not None:
               event.widget.create_line(self.xold,self.yold,event.x,event.y,fill="red",width=3,smooth=TRUE)
           self.xold=event.x
           self.yold=event.y
           self.liste.append((self.xold,self.yold))


if __name__ == "__main__":
    root=Tk()
    app = ExampleApp(root)
    app.pack()
    app.dessiner()
    root.mainloop()

如果你想看看我的问题，那么你可以下载这个 大图像并将其命名为 image.jpg 并运行代码.

If you want to see my problem then you can download this large image and name it image.jpg and run the code.

可能解决方案在于使用 canvasx 和 canvasy 但我不知道怎么做.

May be the solution resides in using canvasx and canvasy but I do not know how.

提前致谢

推荐答案

我通过更改以下几行解决了该问题:

I resolved the problem by changing these lines:

event.widget.create_line(self.xold,self.yold,event.x,event.y,fill="red",width=3,smooth=TRUE)

和:

self.xold=event.x
self.yold=event.y

到:

event.widget.create_line(self.xold,self.yold,self.canvas.canvasx(event.x),self.canvas.canvasy(event.y),fill="red",width=3,smooth=TRUE)

和:

self.xold=self.canvas.canvasx(event.x)
self.yold=self.canvas.canvasy(event.y)

这篇关于TkInter:绘制错误的位置的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！