Shulou(Shulou.com)06/01 Report--

Today, Xiaobian will share with you the relevant knowledge points on how to realize the Tkinter main menu. The content is detailed and the logic is clear. I believe most people still know too much about this knowledge, so share this article for your reference. I hope you will gain something after reading this article. Let's find out together.

Menus are one of the most common controls in GUI programs. This article explains how to use menus in Tkinter.

Mini programs in the video are modified on the basis of the previous Text control sample program, and their functions are basically the same, except that menu operation functions are added. The reader can pay a little attention to the interaction between the Enable/Disable button and the menu item.

The first is to build the main menu object. The code is divided into two steps: one is to build a menu object top_menu with the main window as a parameter, and the other is to set the menu attribute of the main window object with the top_menu object.

Note that pack, grid, etc. are not used here.

top_menu = Menu(root)root.config(menu=top_menu)

The following code adds two subordinate menus to the main menu: edit and format.

There are also two steps to building a subordinate menu: building objects and adding them to the main menu. The parameters used should require little explanation, except tearoff. If you do not set tearoff to False, a horizontal line will appear at the top of the lower menu. The code deliberately specifies tearoff as False for edit_menu and defaults to format menu, and the result can be seen in menu presentation.

edit_menu = Menu(top_menu, tearoff=False)top_menu.add_cascade(label='Edit', menu=edit_menu)format_menu = Menu(top_menu)top_menu.add_cascade(label='Format', menu=format_menu)

The code that follows is a bit longer, and some of it is the same as the previous sample code, so the reader should just pay attention to the menu-related parts.

text_enable = IntVar()text_enable.set(1)

# change state function.def enable_text(): text_enable.set(1)

# change state button.eb = Radiobutton(root,text="Enable", width=8, command=enable_text, value=1, variable=text_enable)eb.grid(row=1, column=0, sticky=E+W)edit_menu.add_radiobutton(label='Enable', command=enable_text, value=1, variable=text_enable)

# change state function.def disable_text(): text_enable.set(0)

# change state button.eb = Radiobutton(root,text="Disable", width=8, command=disable_text, value=0, variable=text_enable)eb.grid(row=1, column=1, sticky=E+W)edit_menu.add_radiobutton(label='Disable', command=disable_text, value=0, variable=text_enable)

The code first constructs a text_enable variable, and then changes the value of this variable when a button or menu action is performed. At the same time, when adding the readiobutton menu item, specify the observation object variable (variable) and the variable value (value) required to display the selected state. This is exactly the same way Rediobutton controls are used.

Next we want to modify the effective state of the Text control, which can be achieved by adding the effective state of the Text control to the enable_text/disable_text method in the above code, or by monitoring the state change of the variable:

def var_changed(*args): if text_enable.get(): text.config(state='normal') text.config(background='#a0ffa0') else: text.config(state='disabled') text.config(background='#efefef')# set variable observer.text_enable.trace_variable('w', var_changed)

Next comes the process of building other generic menu items that readers can understand in conjunction with the button code. The form is slightly different, but the content is exactly the same.

# delete selection.def delete_selection(): try: sel_from = text.index(SEL_FIRST) sel_to = text.index(SEL_LAST) # delete the selection. text.delete(sel_from, sel_to) except TclError: pass

# delete selection button.db = Button(root,text="Delete", width = 8, command=delete_selection)db.grid(row=1, column=2, sticky=E+W)edit_menu.add_radiobutton(label='Delete', command=delete_selection)

# undo buttonundo = Button(root, text='Undo', width = 8, command=lambda:text.edit_undo())undo.grid(row=1, column = 3, sticky=E+W)edit_menu.add_radiobutton(label='Undo', command=lambda:text.edit_undo())

#redo buttonredo = Button(root, text='Redo', width = 8, command=lambda:text.edit_redo())redo.grid(row=1, column = 4, sticky=E+W)edit_menu.add_radiobutton(label='Redo', command=lambda:text.edit_redo())

# create fontsfonts = [ Font(family='SimHei', size=20, weight=BOLD), Font(family='SimHei', size=16), Font(family='SimSun', size=12, weight=BOLD), Font(family='SimSun', size=12) ]

# delete selection.def format(index): tag_name = 'Format' + str(index) try: sel_from = text.index(SEL_FIRST) sel_to = text.index(SEL_LAST) for name in text.tag_names(): text.tag_remove(name, sel_from, sel_to) text.tag_add(tag_name, sel_from, sel_to) # set format at first time. range_count = len(text.tag_ranges(tag_name)) if range_count == 2: text.tag_config(tag_name, font=fonts[index]) except TclError: pass

# delete selection button.for i in range(0, 4): fb = Button(root, text="Format" + str(i), width = 8, command=lambda v=i : format(v)) format_menu.add_command(label="Format" + str(i), command=lambda v=i : format(v)) fb.grid(row=2, column=i, sticky=E+W)

# create text widget.text = Text(root, undo=True, background="#a0ffa0", foreground="#000000", height = 10)text.grid(row=3 , column=0, columnspan=8) The above is "Tkinter main menu how to achieve" All the contents of this article, thank you for reading! I believe everyone has a great harvest after reading this article. Xiaobian will update different knowledge for everyone every day. If you want to learn more knowledge, please pay attention to the industry information channel.

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.