10.2. The Alignment widget
The Alignment widget allows you to place
a widget within its window at a position and size relative to the size of
the Alignment widget itself. For example, it can be
very useful for centering a widget within the window.
There are only two calls associated with the
alignment = gtk.Alignment(xalign=0.0, yalign=0.0, xscale=0.0, yscale=0.0)
alignment.set(xalign, yalign, xscale, yscale)
The gtk.Alignment() function creates a new
Alignment widget with the specified parameters. The
set() method allows the alignment parameters of an
existing Alignment widget to be altered.
All four alignment parameters are floating point numbers which
can range from 0.0 to 1.0. The xalign and
yalign arguments affect the position of the widget
placed within the gtk.Alignment
widget. The align properties specify the fraction of
free space that will be placed above or to the left of
the child widget. The values range from 0.0 (no free
space above or to the left of the child) to 1.0 (all
free space above or to the left of the child). Of
course, if the scale properties are both set to 1.0, the alignment
properties have no effect since the child widget will expand to fill the
The xscale and
yscale arguments specify the fraction of
free space absorbed by the child widget. The values can
range from 0.0 (meaning the child absorbs none) to 1.0 (meaning the child
absorbs all of the free space).
A child widget can be added to this
Alignment widget using:
For an example of using an Alignment
widget, refer to the progressbar.py
example for the Progress Bar widget.