Scott L. Johnson wrote in message <5911@palm-dev-forum>...
>
>> From: Richard M. Hartman [mailto:[EMAIL PROTECTED]]
>> What does the OS normally do for memory management
>> on label objects on forms? Likewise, what must I do if
>> I am going to mess w/ the label text?
>
>When a form is initially loaded, the text pointer in every control (and
>label, etc) points to a string of bytes that is embedded inside the form
>object itself. The entire form object itself is a single chunk in the
>dynamic heap.
>
>When you close a form, the OS basically just frees the single chunk that
>constitutes the form object. It does not attempt to free any other memory
>chunks that may be referenced by the various pointers in controls and
labels
>within the form. It just assumes that nothing got changed, so that the
>controls and labels still point to the embedded strings within the form
>object.
...
>The key to all this is to understand exactly who (you -or- the form object)
>owns the memory you're about to fiddle with. If you own it, then you need
>to clean it up.
Ok, your explanation makes it pretty clear for labels. I can see how
their original text is part of the resource so the pointers are "included"
when you deallocate the form resource as a whole.
But now what about fields (using FldSetTextHandle() & FldGetTextHandle())?
The documentation states:
If the previous text handle points to a string on the dynamic heap
and you want to free it, use FldGetTextHandle
But that is a big "if" there ... does the initial handle for a field point
to
a string on the dynamic heap? If so, I am responsible for freeing it
if I replace it with my own handle, if not then I am not responsible. So I
know what to do for each answer but I don't know the answer....
--
-Richard M. Hartman
[EMAIL PROTECTED]
186,000 mi/sec: not just a good idea, it's the LAW!
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