Ruby/TK - The pack geometry manager



Description

The pack geometry manager organizes widgets in rows or columns inside the parent window or the widget. To manage widgets easily, the pack geometry manager provides various options, such as fill, expand, and side.

  • fill − The fill option is used to specify whether a widget should occupy all the space given to it by the parent window or the widget. Some of the possible values that can be used with this option are none, x, y, or both. By default, the fill option is set to none.

  • expand − The expand option is used to specify whether a widget should expand to fill any extra space available. The default value is 0, which means that the widget is not expanded. The other value is 1.

  • side − The side option is used to specify the side against which the widget is to be packed. Some of the possible values that can be used with this option are top, left, bottom, or right. By default, the widgets are packed against the top edge of the parent window.

Syntax

Here is a simple syntax to create a pack Widget −

 pack('padx'=>10, 'pady'=>10, 'side'=>'left')

Examples

Following is the code to display the Label and an Entry widget using the pack geometry manager −

require 'tk'

top = TkRoot.new {title "Label and Entry Widget"}

#code to add a label widget
lb1 = TkLabel.new(top) {
   text 'Hello World'
   background "yellow"
   foreground "blue"
   pack('padx'=>10, 'pady'=>10, 'side'=>'left')
}

#code to add a entry widget
e1 = TkEntry.new(top) {
   background "red"
   foreground "blue"
   pack('padx'=>10, 'pady'=>10, 'side'=>'left')
}

Tk.mainloop

This will produce the following result−

Ruby/Tk Pack
ruby_tk_guide.htm
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