The progressbar widget changes its visual appearance each time the
value or the
max option is set. For example, the default value for
0 and the default value for
100. So when the progressbar widget is displayed with these values, we don't actually see the graphical bar, yet that depicts the progress percentage. However, setting the
value option will update this bar. If the bar is already visible, a change in the
value option results in a change of the width for the progressbar. These changes, using the default progressbar implementation, simply change the widget instantaneously. Let's look at how we can modify the widget to support a smooth transition between progressbar values.
We'll use ...