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Re: [ve-dev] running sweet
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Mark Proctor wrote:
I've just seen that CompositeTable does implement virtual tables,
although not quite sure how that works - seems to create a new internal
table for each redraw.
Nope. When you build a UI, you create a custom control that extends
Composite. You drop this into CompositeTable to tell CompositeTable
what your row looks like. CompositeTable uses reflection to get a
Constructor object (the Star Trek replicator (tm) object) and then
duplicates your row object for as many rows as are visible at a given
time. Scrolling is implemented by rearranging these Composites. For
example, to scroll down by a line, CompositeTable does the following:
- Move every row object up by 1 row.
- Move the top row object to the bottom row position.
- Fire a row refresh event to ask the content provider to refresh the
bottom row with new data.
So redraws are very efficient. On Linux/GTK my keyboard can't repeat
enough to cause CompositeTable to get behind, although there are a few
other places where the Linux/GTK implementation is slow enough that my
keyboard autorepeat can out-type it.
Does a Composite per row mean you wont be able to
do vertical merges?
Not sure what you mean here?
Best,
Dave Orme
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