Volume 6A: Motif Programming Manual

Output of text_form.c

Notice that the Labels are centered vertically with respect to their corresponding Text widgets. This arrangement

happened because each Label was stretched vertically in order to attach it to the top and bottom of the respective

Form. Of course, if the Labels were higher than the Text widgets, the Text widgets would be stretched instead.

Later, we'll show another version of this program that gives better results. As you can imagine, there are many

different ways for a Form, or any other manager widget, to manage the geometry of its children to produce the same

layout. Later, when we discuss the RowColumn widget, we will show you another solution to the problem of

horizontal alignment. It is important to remember that there is no right or wrong way to create a layout, as long as it

works for your application. However, you should be very careful to experiment with resizing issues as well as with

resources that can be set by the user that might affect widget layout, such as fonts and strings.

9.4.6 Common Problems

With a Form widget, you can specify a virtually unlimited number of attachments for its children. The dependencies

inherent in these attachments can lead to various errors in the layout of the widgets. One common problem involves

circular dependencies. The following code fragment shows a very simple example of a circular dependency:

w1 = XtVaCreateManagedWidget ...