Displaying a pop-up menu

A pop-up menu is exactly as the name implies: a menu that appears arbitrarily. It is accessed via a user action (normally a mouse click). The menu is created as normally, but is accessed by binding to an event. The actual display of the menu is accomplished by the tk_popup command.

The syntax is as follows:

tk_popup name x y

How to do it…

In the following example, we will create a menu that contains an option to exit a window. Create the following text file and save it in your working path with the name my_popup.tcl:

# Load the TK Package
package require Tk
#Define our interface
wm geometry . 320x240
wm title . "Menu Example"
# Create a menu to exit our window
set File [menu .popup]
# Add the Exit entry
$File add command -label Exit -command exit
# Now we add a label to bind to
label .l -text "Click here to access your menu"
pack .l
# Now bind to the right mouse click
bind .l <3> {tk_popup .popup %X %Y}

Now launch the program by invoking the following command...