Consider a license agreement (this is not what I am doing, but it
illustrates the need). You have a form of mostly text, and at the bottom of
the form there is an OK button that appears only when you have scrolled down
to the bottom.

It is NOT impossible. In the AvantGo application they are DOING IT! HOW?

For those of you who have access to it, you can click on the ad on the front
page, and you will enter a page with both horizontal and vertical
scrollbars, that contains images, static text, text fields, checkboxes and a
button as well, all of which looks like the normal form elements. However,
you can scroll the elements half off the screen and still use them! This
means that whenever the elements within are drawn (also on pen-down, text
input etc, which the PalmOS is (normally) handling for you), a clipping
rectangle must be active to prevent the elements from drawing outside the
area and obscuring the scroll bars or title.

Either there is some feature in PalmOS that I haven't fount yet that enables
some form elements to be contained within a clipping rectangle (wouldn't
that be neat), or they have a jolly complicated system at AvantGo for
enabling and disabling the clip rect while drawing different form items, and
moving the elements of the form around when scrolling occurs. Also, when
they are scrolling, they are obviously only drawing the thin areas that are
appearing along the edges, otherwise the scrolling would not appear so
smooth.

Would anyone at AvantGo please give up this code for the public good? Or
would some programming experts at Palm please reinvent it and release it to
us? I have searched all the 27000 messages in this forum and I can say that
the topic comes up quite often, but since this is obviously a shortcoming of
the operating system, the least that Palm could provide is a good example
program on how to work around it.


Regards,
Roar Lauritzsen




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