Question

我正在编写一个小程序，它从SQLite DB中获取输入，并根据Combobox中的选择在GUI中打印出信息。基本上它是游戏自由职业者的交易信息（这些商品在特定的基础上出售）。我得到它的工作，它打印出树视图中的第一个选择。但是，当我想要打印下一个（不同的）选择时，它不会刷新，但会在第一个之后创建一个新的Treeview。我尝试了几个东西，包括一个destroy（），但我无法让它工作。以下是我写的代码。我编辑了一些固定数据而不是从SQLite DB中提取数据。 “Bases”按钮填充组合框。 “基本销售的商品”按钮采用组合框的选择并生成树视图。

from Tkinter import *
import csv, sqlite3, sys
from ttk import Combobox, Treeview

root = Tk()
root.minsize(width=500, height=300)

v = StringVar() # ========= v is a variable that stores the selection(s) from the combobox ============
dropdownBases = []
goodsSoldAtBase = []
tree_header = []

def on_field_change(index, value, op):
    v = boxBases.get()
    print 'v is', v

def List_bases():
    data = ['base1', 'base2', 'base3', 'base4',]
    for i in data:
        dropdownBases.append(i)
    boxBases.config(values=dropdownBases)

def List_sold_at_base():

    destroy_widget()

    sb=v.get()
    print sb
    dataFromDB = [['base1', 'Cobalt 275', 'Copper 180'],['base2', 'High Temp Alloy 280', 'Mining Machinery 130'],
    ['base3', 'H-Fuel 240', 'Oxygen 6', 'Water 18'], ['base4', 'Hydrocarbons 40', 'Polymers 107']]
    for i in dataFromDB:
        if i[0] == sb:
            goodsSoldAtBase.append(i[1])
            goodsSoldAtBase.append(i[2])
    # --------------- print for control purpose-------------------
        print i
    print "\n", dataFromDB
    print "\n", goodsSoldAtBase
    tree_header = ["Commodity Name", "Price"]
    #================== build the treeview and populate it =============================
    container = Frame(printLabel)
    container.pack(side= TOP, fill='both', expand=True)

    # create a treeview with scrollbar
    tree = Treeview(columns=tree_header, show="headings")
    vsb = Scrollbar(orient="vertical", command=tree.yview)

    tree.grid(column=0, row=0, sticky='nsew', in_=container)
    vsb.grid(column=1, row=0, sticky='ns', in_=container)
    container.grid_columnconfigure(0, weight=1)
    container.grid_rowconfigure(0, weight=1)

    for col in tree_header:
        tree.heading(col, text=col.title())

    for item in goodsSoldAtBase:
        tree.insert('', 'end', values=item)
        # adjust column's width if necessary to fit each value

def destroy_widget():
    try:
        container.destroy()
    except:
        pass

def selection(event):
    v=boxBases.current()

def file_menu():

    root.title("Freelancer trade helper")
    menubar = Menu(root)
    root.config(menu=menubar)

    fileMenu = Menu(menubar)
    fileMenu.add_command(label="Exit", command=quit)
    menubar.add_cascade(label="File", menu=fileMenu)

# ================== Frames ===========================

leftFrame= Frame(root)
leftFrame.pack(side=LEFT, fill=BOTH)

rightFrame= Frame(root)
rightFrame.pack(side=RIGHT, fill=BOTH, expand=TRUE)

printLabel = Label(rightFrame, relief=SUNKEN)
printLabel .pack(side=BOTTOM, fill=BOTH, expand=TRUE)



# ================== Buttons ==========================

boxBases = Combobox(rightFrame, textvar=v, values=dropdownBases)
boxBases.bind('<<ComboboxSelected>>', selection)
boxBases.pack(side=TOP, anchor=NW, fill=X)

baseButton=Button(leftFrame, text="Bases", command=List_bases)
baseButton.pack(side=TOP, anchor=W, fill=X)

goodsButton = Button(leftFrame, text="Goods sold at base", command=List_sold_at_base)
goodsButton.pack(side=TOP)

file_menu()
root.mainloop()

Answer 1

为什么不清除旧数据并将新数据放在同一个小部件中，而不是销毁和重新制作整个小部件？

在Tkinter

1 个答案: