On 2/11/19 1:22 PM, Huw Davies wrote:
On Mon, Feb 11, 2019 at 01:09:14PM +0200, Gabriel Ivăncescu wrote:
On 2/11/19 12:10 PM, Huw Davies wrote:
On Fri, Feb 08, 2019 at 02:41:45PM +0200, Gabriel Ivăncescu wrote:
@@ -1535,36 +1552,42 @@ static LRESULT LISTBOX_InsertItem( LB_DESCR *descr, INT index, if (index == -1) index = descr->nb_items; else if ((index < 0) || (index > descr->nb_items)) return LB_ERR;
- if (!resize_storage(descr, descr->nb_items + 1)) return LB_ERR;
- /* Insert the item structure */
- item = &descr->items[index];
- if (index < descr->nb_items)
RtlMoveMemory( item + 1, item,(descr->nb_items - index) * sizeof(LB_ITEMDATA) );- item->str = str;
- item->data = HAS_STRINGS(descr) ? 0 : data;
- item->height = 0;
- item->selected = FALSE;
- descr->nb_items++;
- /* Get item height */
- if (descr->style & LBS_OWNERDRAWVARIABLE)
- if (is_singlesel_NODATA(descr)) {
MEASUREITEMSTRUCT mis;UINT id = (UINT)GetWindowLongPtrW( descr->self, GWLP_ID );
descr->nb_items++;descr->items_size = max(descr->items_size, descr->nb_items);- }
- else
- {
if (!resize_storage(descr, descr->nb_items + 1)) return LB_ERR;Again, resize_storage will handle the no_data case. Then add a helper to actually insert the item.
But in the insert helper, I'd have to ignore everything if it's single-selection LBS_NODATA (because there's nothing to do), so there is no difference to currently except just moving most of the function into a helper (instead of indenting it).
Is that what you had in mind?
Yes.
@@ -1678,19 +1701,29 @@ static LRESULT LISTBOX_RemoveItem( LB_DESCR *descr, INT index ) LISTBOX_InvalidateItems( descr, index ); descr->nb_items--;
- LISTBOX_DeleteItem( descr, index );
LB_DeleteItem should again handle the no_data case, it'll send LB_RESETCONTENT as required.
Shouldn't that be RemoveItem? DeleteItem, AFAIK, has to not be called with LBS_NODATA (unless you simply mean an early exit if so) nor send any messages at all.
It's an earlish exit after sending the LB_RESETCONTENT message if appropriate.
@@ -1729,7 +1762,8 @@ static void LISTBOX_ResetContent( LB_DESCR *descr ) { INT i;
- for(i = descr->nb_items - 1; i>=0; i--) LISTBOX_DeleteItem( descr, i);
- if (descr->items)
for (i = descr->nb_items - 1; i >= 0; i--) LISTBOX_DeleteItem(descr, i);LB_DeleteItems() will cope.
I don't like this solution. That would be slower than needed for large lists (which LBS_NODATA is for) when resetting them, for an operation that should basically be instant and not dependent on the list's size. i.e. from O(1) to O(n)
We'll revisit it if performance turns out to be an issue.
Huw.
Well, I find it awkward that sending SetCount to zero first would be far faster than LB_RESETCONTENT directly (that's what this will turn out to be), or that "growing" the list is instant while ResetContent is not. And it's just one line of code, I think when reducing O(n) to O(1) it should be worth it, given the point of LBS_NODATA.
(also, a variant of that line of code will also help with multi-selection listboxes later, which can also be instant)