Tkinter

This term has different meanings in different contexts, but in general it refers to a rectangular area somewhere on the user's display screen.

A window which acts as a child of the primary window. It will be decorated with the standard frame and controls for the desktop manager. It can be moved around the desktop and can usually be resized.

The generic term for any of the building blocks that make up an application in a graphical user interface.

• Core widgets: The containers: frame, labelframe, toplevel, paned window. The buttons: button, radiobutton, checkbutton (checkbox), and menubutton. The text widgets: label, message, text. The entry widgets: scale, scrollbar, listbox, slider, spinbox, entry (singleline), optionmenu, text (multiline), and canvas (vector and pixel graphics).
• Tkinter provides three modules that allow pop-up dialogs to be displayed: tk.messagebox (confirmation, information, warning and error dialogs), tk.filedialog (single file, multiple file and directory selection dialogs) and tk.colorchooser (colour picker).
• Python 2.7 and Python 3.1 incorporate the "themed Tk" ("ttk") functionality of Tk 8.5.[6][7] This allows Tk widgets to be easily themed to look like the native desktop environment in which the application is running, thereby addressing a long-standing criticism of Tk (and hence of Tkinter). Some widgets are exclusive to ttk, such as the combobox, progressbar, treeview, notebook, separator and sizegrip.[8]

In Tkinter, the Frame widget is the basic unit of organization for complex layouts. A frame is a rectangular area that can contain other widgets.

When any widget is created, a parent–child relationship is created. For example, if you place a text label inside a frame, the frame is the parent of the label.

There are four stages to creating a widget[11]

Create

create it within a frame

Configure

change the widgets attributes.

Pack

pack it into position so it becomes visible. Developers also have the option to use .grid() (row=int, column=int to define rows and columns to position the widget, defaults to 0) and .place() (relx=int or decimal, rely=int or decimal, define coordinates in the frame, or window).

Bind

bind it to a function or event.

These are often compressed, and the order can vary.

Using the object-oriented paradigm in Python, a simple program would be (requires Tcl version 8.6, which is not used by Python on MacOS by default):

#!/usr/bin/env python3
import tkinter as tk


class Application(tk.Frame):

    def __init__(self, root=None):
        tk.Frame.__init__(self, root)
        self.grid()
        self.createWidgets()

    def createWidgets(self):
        self.medialLabel = tk.Label(self, text='Hello World')
        self.medialLabel.config(bg="#00ffff")
        self.medialLabel.grid()
        self.quitButton = tk.Button(self, text='Quit', command=self.quit)
        self.quitButton.grid()


app = Application()
app.root.title('Sample application')
app.mainloop()

• line 1: Hashbang directive to the program launcher, allowing the selection of an appropriate interpreter executable, when self-executing.[12]
• line 2: Imports the tkinter module into your program's namespace, but renames it as tk.
• line 5: The application class inherits from Tkinter's Frame class.
• line 7: Defines the function that sets up the Frame.
• line 8: Calls the constructor for the parent class, Frame.
• line 12: Defining the widgets.
• line 13: Creates a label, named MedialLabel with the text "Hello World".
• line 14: Sets the MedialLabel background colour to cyan.
• line 15: Places the label on the application so it is visible using the grid geometry manager method.
• line 16: Creates a button labeled “Quit”.
• line 17: Places the button on the application. Grid, place and pack are all methods of making the widget visible.
• line 20: The main program starts here by instantiating the Application class.
• line 21: This method call sets the title of the window to “Sample application”.
• line 22: Starts the application's main loop, waiting for mouse and keyboard events.