So far, we have laid out our widgets in a very basic manner.
We have set absolute positions and sizes
and we have specified the position within the parent and the size at which
a widget should be shown. This process is generally not desirable. It makes
the window that contains the widgets (often a dialog box) look bad when
it is resized. If the size of this window is increased, an empty space will
appear at the right and lower borders of the window because
the widgets stay at their fixed positions and do not fill the newly
available space. If, on the other hand, the size of the window is
decreased, some widgets will not be visible any longer, or the window might
appear incomplete. Again, this occurs because the widgets do
not occupy less space and use less intrawidget space to
accommodate the smaller parent window.
Another disadvantage comes from internationalization. When you prepare your program to display text in different languages, on-screen text in different languages are rarely the same size. If you design your dialog boxes with English labels and then have your application translated into a language such as Finnish, in which the average word length is long, the text will probably not fit into the allocated space.
The solution to these two problems is geometry management, also called layout management. When using geometry management, sizes and positions ...