Unfortunately, I don't know of any books on subforms in Designer but maybe a sample form will help you understand a little more about how things work.
Catherine was suggesting using a text field with its height set as "expandable" placed in a flowed subform such that if the text entered in the text field is too long to fit in its entirety, the text field would expand in height and push the rest of the form downward, thereby ensuring that all the text entered into the comment text field is visible when printed and the remainder of the form is still visible and unobstructed as well.
I've applied her suggestions to a sample form.
Because I knew I wanted an expandable Comments section in the middle of my form (such that when comments are entered, if they're too long to fit in the space initially provided, the Comments section would expand in height and move the bottom section downward), I started by creating 3 subforms on the page: TopSubform, CommentsSubform (in the middle) and BottomSubform. All these subforms were made to be as wide as the page subform and as tall as required to fit their respective fields.
In the middle subform (CommentsSubform), I placed a text field with these modifications: I removed the caption (using the Position property at the bottom of the Layout palette), made its height expandable (checked the
Expand to fit property on the Layout palette as well) and made it multi-lined (
Allow Multiple Lines property on the Object palette's Field tab).
In order to ensure that the text field in the CommentsSubform can expand in height and push the BottomSubform downwards, I then made the CommentsSubform's content
Flowed by using the Content property on the Object palette's Subform tab.
The last step, which brings this all together, was to give a
Flowed content to the page subform which contains all 3 subforms defined earlier. This way, when the text field in the CommentsSubform expands in height, the form's layout will reflow and cause the BottomSubform to shift downward to accommodate the length of the comment specified by the user. This is also the reason why I placed the top and bottom form fields in subforms as well because I wanted to
position these fields in precise locations. I could've placed all fields in the page subform, made the page subform flowed and have it work as well but I wouldn't have had any control over the position of the fields.
I hope this clarifies things about subforms and helps you fix your form as well.
Note:
The expandable comment text field doesn't expand as your entering text into it. It'll expand only once you tab or click out of it.
Stefan
Adobe Systems