Super Simplified Web Browser

main.py

import tkinter as tk
import urllib.request
import io
from PIL import Image, ImageTk
from urllib.parse import urljoin
from html.parser import HTMLParser
from tkx import VerticalScrolledFrame

class MyHTMLParser(HTMLParser):
    def __init__(self, parent):
        super().__init__()
        self.cur_tag = None
        self.cur_attrs = None
        self.cur_url = ""
        self.parent = parent

    def handle_starttag(self, tag, attrs):
        self.cur_tag = tag
        self.cur_attrs = {attr[0]:attr[1] for attr in attrs}
        if self.cur_tag == 'img':
            src = self.cur_attrs['src']
            if src != "http":
                src = urljoin(self.cur_url, src)
            with urllib.request.urlopen(src) as f:
                pilimg = Image.open(io.BytesIO(f.read()))
                img = ImageTk.PhotoImage(pilimg)
                self.parent.add_image(img)
            return

    def handle_data(self, data):
        if self.cur_tag == "a":
            href = self.cur_attrs['href']
            if href != "http":
                href = urljoin(self.cur_url, href)
            self.parent.add_link(data, href)
            return
        if self.cur_tag not in ['script', 'style'] and data.strip() != "":
            self.parent.add_text(data)

class Application(tk.Frame):
    def __init__(self, master=None):
        super().__init__(master)
        self.parser = MyHTMLParser(self)
        self.master = master
        self.cache = []
        self.pack(expand=1, fill=tk.BOTH, anchor=tk.NW)
        self.create_widgets()

    def create_widgets(self):
        # URL入力バー
        self.url_bar = tk.Entry(self)
        self.url_bar.grid(column = 0, row = 0, sticky = 'nsew')
        self.url_bar.insert(tk.END, 'https://www.google.com/')
        # 移動ボタン
        self.url_button = tk.Button(self, text="GO", command=self.enter_url, fg='RED')
        self.url_button.grid(column = 1, row = 0, sticky = 'nsew')
        self.columnconfigure(0, weight=1)
        # ページフレーム
        self.page = VerticalScrolledFrame(self, bg='WHITE')
        self.page.grid(column = 0, row = 1, columnspan= 2, sticky = 'nsew')
        self.rowconfigure(1, weight=1)

    def reset_page(self):
        for widget in self.page.interior.winfo_children():
            widget.pack_forget()

    def enter_url(self):
        #ページをリセット
        self.reset_page()
        # URLを取得
        url = self.url_bar.get()
        self.parser.cur_url = url
        # GETリクエスト
        with urllib.request.urlopen(url) as f:
            data = f.read().decode('utf-8')
        self.parser.feed(data)
    
    def add_text(self, data):
        x1 = tk.Label(self.page.interior, text=data, bg='WHITE')
        x1.pack()

    def add_link(self, data, href):
        x1 = tk.Button(self.page.interior, text=data, bg='WHITE',
            command=lambda:(
                self.url_bar.delete(0, tk.END),
                self.url_bar.insert(tk.END, href),
                self.enter_url(),
                )
            )
        x1.pack()

    def add_image(self, img):
        self.cache.append(img)
        x1 = tk.Label(self.page.interior, image=img)
        x1.pack()

root = tk.Tk()
root.geometry('800x600')
app = Application(master=root)
app.mainloop()

tkx.py

from tkinter import *

class VerticalScrolledFrame(Frame):
    """A pure Tkinter scrollable frame that actually works!
    * Use the 'interior' attribute to place widgets inside the scrollable frame
    * Construct and pack/place/grid normally
    * This frame only allows vertical scrolling

    """
    def __init__(self, parent, *args, **kw):
        Frame.__init__(self, parent, *args, **kw)            

        # スクロールバーの作成
        vscrollbar = Scrollbar(self, orient=VERTICAL)
        vscrollbar.pack(fill=Y, side=RIGHT, expand=FALSE)
        canvas = Canvas(self, bd=0, highlightthickness=0,
                        yscrollcommand=vscrollbar.set, bg='WHITE')
        canvas.pack(side=LEFT, fill=BOTH, expand=TRUE)
        vscrollbar.config(command=canvas.yview)

        # ビューをリセット
        canvas.xview_moveto(0)
        canvas.yview_moveto(0)

        # create a frame inside the canvas which will be scrolled with it
        self.interior = interior = Frame(canvas, bg='WHITE')
        interior_id = canvas.create_window(0, 0, window=interior,
                                           anchor=NW)

        # track changes to the canvas and frame width and sync them,
        # also updating the scrollbar
        def _configure_interior(event):
            # update the scrollbars to match the size of the inner frame
            size = (interior.winfo_reqwidth(), interior.winfo_reqheight())
            canvas.config(scrollregion="0 0 %s %s" % size)
            if interior.winfo_reqwidth() != canvas.winfo_width():
                # update the canvas's width to fit the inner frame
                canvas.config(width=interior.winfo_reqwidth())
        interior.bind('<Configure>', _configure_interior)

        def _configure_canvas(event):
            if interior.winfo_reqwidth() != canvas.winfo_width():
                # update the inner frame's width to fill the canvas
                canvas.itemconfigure(interior_id, width=canvas.winfo_width())
        canvas.bind('<Configure>', _configure_canvas)