tkinter example demopanels (snippet)

Python tkinter (gui) example 'demopanels'

Modules used in program:

• import inspect

demopanels

Python tkinter example: demopanels

from tkinter import *
from tkinter import ttk
from tkinter.simpledialog import Dialog
from PIL import Image, ImageTk
import inspect

class MsgPanel(ttk.Frame):
    def __init__(self, master, msgtxt):
        ttk.Frame.__init__(self, master)
        self.pack(side=TOP, fill=X)

        msg = Label(self, wraplength='4i', justify=LEFT)
        msg['text'] = ''.join(msgtxt)
        msg.pack(fill=X, padx=5, pady=5)

class SeeDismissPanel(ttk.Frame):
    def __init__(self, master):
        ttk.Frame.__init__(self, master)
        self.pack(side=BOTTOM, fill=X)          # resize with parent

        # separator widget
        sep = ttk.Separator(orient=HORIZONTAL)

        # Dismiss button
        #im = Image.open('images//delete.png')   # image file
        #imh = ImageTk.PhotoImage(im)            # handle to file
        dismissBtn = ttk.Button(text='Dismiss', command=self.winfo_toplevel().destroy)
        #dismissBtn.image = imh                  # prevent image from being garbage collected
        dismissBtn['compound'] = LEFT           # display image to left of label text

        # 'See Code' button
        #im = Image.open('images//view.png')
        #imh = ImageTk.PhotoImage(im)
        codeBtn = ttk.Button(text='See Code', default=ACTIVE, command=lambda: CodeDialog(self.master))
        #codeBtn.image = imh
        codeBtn['compound'] = LEFT
        codeBtn.focus()

        # position and register widgets as children of this frame
        sep.grid(in_=self, row=0, columnspan=4, sticky=EW, pady=5)
        codeBtn.grid(in_=self, row=1, column=0, sticky=E)
        dismissBtn.grid(in_=self, row=1, column=1, sticky=E)

        # set resize constraints
        self.rowconfigure(0, weight=1)
        self.columnconfigure(0, weight=1)

        # bind <Return> to demo window, activates 'See Code' button;
        # <'Escape'> activates 'Dismiss' button
        self.winfo_toplevel().bind('<Return>', lambda x: codeBtn.invoke() )
        self.winfo_toplevel().bind('<Escape>', lambda x: dismissBtn.invoke() )

class CodeDialog(Dialog):
    """Create a modal dialog to display a demo's source code file. """

    def body(self, master):
        """Overrides Dialog.body() to populate the dialog window with a scrolled text window
        and custom dialog buttons. """

        # get the full path of this object's parent source code file
        fileName = inspect.getsourcefile(self.parent._create_widgets)

        self.title('Source Code: ' + fileName)

        # create scrolled text widget
        txtFrame = ttk.Frame(self)
        txtFrame.pack(side=TOP, fill=BOTH)

        text = Text(txtFrame, height=24, width=100, wrap=WORD, setgrid=1, highlightthickness=0, pady=2, padx=3)
        xscroll = ttk.Scrollbar(txtFrame, command=text.xview, orient=HORIZONTAL)
        yscroll = ttk.Scrollbar(txtFrame, command=text.yview, orient=VERTICAL)
        text.configure(xscrollcommand=xscroll.set, yscrollcommand=yscroll.set)

        # position in frame and set resize constraints
        text.grid(row=0, column=0, sticky=NSEW)
        yscroll.grid(row=0, column=1, sticky=NSEW)
        txtFrame.rowconfigure(0, weight=1)
        txtFrame.columnconfigure(0, weight=1)

        # add text of file to scrolled text widget
        text.delete('0.0', END)
        text.insert(END, open(fileName).read())

    def buttonbox(self):
        """Overrides Dialog.buttonbox() to create custom buttons for this dialog. """

        box = ttk.Frame(self)

        # Cancel button
        cancelBtn = ttk.Button(box, text='Cancel', command=self.cancel)       
        cancelBtn.pack(side=RIGHT, padx=5, pady=5)
        self.bind('<Return>', self.cancel)
        self.bind('<Escape>', self.cancel)

        box.pack()

Useful links

• Learn Tkinter: https://pythonbasics.org/tkinter/
• Wikipedia tkinter: https://en.wikipedia.org/wiki/Tkinter