按钮命令Tkinter Python的问题

Question

So I have this program that searches the SEC Edgar database for annual reports (10-K's), and returns a list of 40 different items in a listbox. Well I want to create a 'Next 40' button which displays the next 40 items in the listbox, which the following code accomplishes:

def Next():

global entryWidget

page = 'http://www.sec.gov/cgi-bin/browse-edgar?company=&match=&CIK=' + entryWidget.get().strip() + '&filenum=&State=&Country=&SIC=&owner=exclude&Find=Find+Companies&action=getcompany'
sock = urllib.urlopen(page)
raw = sock.read()
soup = BeautifulSoup(raw)

npar = str(soup.find(value="Next 40"))
index = npar.find('/cgi')
index2 = npar.find('count=40') + len('count=40')
nextpage = 'http://www.sec.gov' + npar[index:index2]

sock2 = urllib.urlopen(nextpage)
raw2 = sock2.read()
soup2 = BeautifulSoup(raw2)

psoup = str(soup2.findAll(nowrap=True))

myparser = MyParser()
myparser.parse(psoup)

filinglist = myparser.get_descriptions()
linklist = myparser.get_hyperlinks()

filinglist = [s for s in filinglist if s != 'Documents']
filinglist = [s for s in filinglist if s != 'Documents Interactive Data']
filinglist = [s for s in filinglist if not re.match(r'\d{3}-', s)]

linklist = [s for s in linklist if not s.startswith('/cgi-')]

Lb1.delete(0, END)

counter = 0

while counter < len(filinglist):
    Lb1.insert(counter, filinglist[counter])
    counter = counter +1

As you can see when the button is pressed, it reads the original link (page) than looks for the "Next 40" hyperlink on the html website (page). It then parses the new html document (nextpage), then subsequently gets the item names and associated links. Now this code successfully goes to the next page from the original page, but it can only display the one next page.

So how would I be able to make (nextpage) into the original (page) and then be able to list the items from the (nextnextpage) html document everytime I press the 'Next' button? Sorry if that was confusing, I don't really know any other way to explain it.

For more clarification here is the actual site link I want to parse: http://www.sec.gov/cgi-bin/browse-edgar ... getcompany I want the 'Next' button to keep retrieving the html hyperlink from that sites 'Next 40' button.

Here is my entire program code in case you need it:

import BeautifulSoup
from BeautifulSoup import BeautifulSoup
import urllib
import sgmllib
from Tkinter import *
import tkMessageBox
import re

class MyParser(sgmllib.SGMLParser):

def parse(self, psoup):
    self.feed(psoup)
    self.close()

def __init__(self, verbose=0):
    sgmllib.SGMLParser.__init__(self, verbose)
    self.descriptions = []
    self.hyperlinks = []
    self.inside_td_element = 0
    self.starting_description = 0

def start_td(self, attributes):
    for name, value in attributes:
        if name == "nowrap":
            self.inside_td_element = 1
            self.starting_description = 1

def end_td(self):
    self.inside_td_element = 0

def start_a(self, attributes):
    for name, value in attributes:
        if name == "href":
            self.hyperlinks.append(value)

def handle_data(self, data):
    if self.inside_td_element:
        if self.starting_description:
            self.descriptions.append(data)
            self.starting_description = 0
        else:
            self.descriptions[-1] += data

def get_descriptions(self):
    return self.descriptions

def get_hyperlinks(self):
    return self.hyperlinks

def Submit():

global entryWidget

if entryWidget.get().strip() == "":
    tkMessageBox.showerror("Tkinter Entry Widget", "Enter a text value")
else:
    page = 'http://www.sec.gov/cgi-bin/browse-edgar?company=&match=&CIK=' + entryWidget.get().strip() + '&filenum=&State=&Country=&SIC=&owner=exclude&Find=Find+Companies&action=getcompany'
    sock = urllib.urlopen(page)
    raw = sock.read()
    soup = BeautifulSoup(raw)
    psoup = str(soup.findAll(nowrap=True))
    myparser = MyParser()
    myparser.parse(psoup)

    filinglist = myparser.get_descriptions()
    linklist = myparser.get_hyperlinks()

    filinglist = [s for s in filinglist if s != 'Documents']
    filinglist = [s for s in filinglist if s != 'Documents Interactive Data']
    filinglist = [s for s in filinglist if not re.match(r'\d{3}-', s)]

    linklist = [s for s in linklist if not s.startswith('/cgi-')]

    counter = 0

    while counter < len(filinglist):
        Lb1.insert(counter, filinglist[counter])
        counter = counter +1

    downloadbutton.configure(state=NORMAL)
    nextbutton.configure(state=NORMAL)

def Next():

global entryWidget

page = 'http://www.sec.gov/cgi-bin/browse-edgar?company=&match=&CIK=' + entryWidget.get().strip() + '&filenum=&State=&Country=&SIC=&owner=exclude&Find=Find+Companies&action=getcompany'
sock = urllib.urlopen(page)
raw = sock.read()
soup = BeautifulSoup(raw)

npar = str(soup.find(value="Next 40"))
index = npar.find('/cgi')
index2 = npar.find('count=40') + len('count=40')
nextpage = 'http://www.sec.gov' + npar[index:index2]

sock2 = urllib.urlopen(nextpage)
raw2 = sock2.read()
soup2 = BeautifulSoup(raw2)

psoup = str(soup2.findAll(nowrap=True))

myparser = MyParser()
myparser.parse(psoup)

filinglist = myparser.get_descriptions()
linklist = myparser.get_hyperlinks()

filinglist = [s for s in filinglist if s != 'Documents']
filinglist = [s for s in filinglist if s != 'Documents Interactive Data']
filinglist = [s for s in filinglist if not re.match(r'\d{3}-', s)]

linklist = [s for s in linklist if not s.startswith('/cgi-')]

Lb1.delete(0, END)

counter = 0

while counter < len(filinglist):
    Lb1.insert(counter, filinglist[counter])
    counter = counter +1

previousbutton.configure(state=NORMAL)
nextbutton.configure(state=DISABLED)

def Previous():

global entryWidget

page = 'http://www.sec.gov/cgi-bin/browse-edgar?company=&match=&CIK=' + entryWidget.get().strip() + '&filenum=&State=&Country=&SIC=&owner=exclude&Find=Find+Companies&action=getcompany'
sock = urllib.urlopen(page)
raw = sock.read()
soup = BeautifulSoup(raw)

psoup = str(soup.findAll(nowrap=True))

myparser = MyParser()
myparser.parse(psoup)

filinglist = myparser.get_descriptions()
linklist = myparser.get_hyperlinks()

filinglist = [s for s in filinglist if s != 'Documents']
filinglist = [s for s in filinglist if s != 'Documents Interactive Data']
filinglist = [s for s in filinglist if not re.match(r'\d{3}-', s)]

linklist = [s for s in linklist if not s.startswith('/cgi-')]

Lb1.delete(0, END)

counter = 0

while counter < len(filinglist):
    Lb1.insert(counter, filinglist[counter])
    counter = counter +1

nextbutton.configure(state=NORMAL)
previousbutton.configure(state=DISABLED)

if __name__ == "__main__":

root = Tk()
root.title("SEC Edgar Search")
root["padx"] = 10
root["pady"] = 25

top = Frame(root)
bottom = Frame(root)
bottom2 = Frame(root)
top.pack(side=TOP)
bottom.pack(side=BOTTOM, fill=BOTH, expand=True)
bottom2.pack(side=BOTTOM, fill=BOTH, expand=True)

textFrame = Frame(root)

entryLabel = Label(textFrame)
entryLabel["text"] = "Ticker symbol:"
entryLabel.pack(side=TOP)

entryWidget = Entry(textFrame)
entryWidget["width"] = 15
entryWidget.pack(side=LEFT)

textFrame.pack()

scrollbar = Scrollbar(root)
scrollbar.pack(side=RIGHT, fill=Y)

Lb1 =  Listbox(root, width=20, height=15, yscrollcommand=scrollbar.set, selectmode=EXTENDED)
Lb1.pack()

scrollbar.config(command=Lb1.yview)

submitbutton = Button(root, text="Submit", command=Submit)
submitbutton.pack(in_=bottom2, side=TOP)

downloadbutton = Button(root, text="Download")
downloadbutton.pack(in_=bottom2, side=TOP)
downloadbutton.configure(state=DISABLED)

previousbutton = Button(root, text="Previous 40", command=Previous)
previousbutton.pack(in_=bottom, side=LEFT)
previousbutton.configure(state=DISABLED)

nextbutton = Button(root, text="Next 40", command=Next)
nextbutton.pack(in_=bottom, side=LEFT)
nextbutton.configure(state=DISABLED)

root.mainloop()

Answer 1

Use an Application class instead of globals. Currently you're always downloading the first page. But your application class should cache the 'soup' of the current page, which next uses to get the onClick value from the "Next 40" form button:

class Application(Frame):
    def __init__(self, parent=None):
        Frame.__init__(self, parent)
        self.pack()

        self.top = Frame(self)
        self.bottom = Frame(self)
        self.bottom2 = Frame(self)
        self.top.pack(side=TOP)
        self.bottom.pack(side=BOTTOM, fill=BOTH, expand=True)
        self.bottom2.pack(side=BOTTOM, fill=BOTH, expand=True)
        #... 
        self.submitbutton = Button(self, text="Submit", command=self.submit)
        self.submitbutton.pack(in_=self.bottom2, side=TOP)
        #...

    #...

    def submit(self):
        page = ('http://www.sec.gov/cgi-bin/browse-edgar?company=&match=&CIK=' + 
                 self.entryWidget.get().strip() + 
                '&filenum=&State=&Country=&SIC=&owner=exclude' 
                '&Find=Find+Companies&action=getcompany')
        #...
        self.soup = ...

    def next(self):
        #...
        #there must be a better way than this to extract the onclick value
        #but I don't use/know BeautifulSoup to help with this part

        npar = str(self.soup.find(value="Next 40"))
        index1 = npar.find('/cgi')
        index2 = npar.find('count=40') + len('count=40')  
        page = 'http://www.sec.gov' + npar[index1:index2]

        sock = urllib.urlopen(page)
        raw = sock.read()
        self.soup = BeautifulSoup(raw)

        #...

if __name__ == '__main__':
    root = Tk()
    root.title("SEC Edgar Search")
    root["padx"] = 10
    root["pady"] = 25

    app = Application(root)

    app.mainloop()
    root.destroy()

For each new page the onClick link updates the &Start parameter. So alternatively you could increment a counter for that in your class without bothering to parse the current soup to get the value.