[PATCH v3 4/4] comctl32/listbox: Implement LBS_NODATA for multi-selection listboxes
Gabriel Ivăncescu
gabrielopcode at gmail.com
Wed Feb 27 06:19:17 CST 2019
Use a byte array to store selection state of items, since we don't need any
other data for LBS_NODATA multi-selection listboxes. This improves memory
usage dramatically for large lists, and performance boosts are nice too.
Signed-off-by: Gabriel Ivăncescu <gabrielopcode at gmail.com>
---
dlls/comctl32/listbox.c | 86 +++++++++++++++++++++++++++--------------
1 file changed, 56 insertions(+), 30 deletions(-)
diff --git a/dlls/comctl32/listbox.c b/dlls/comctl32/listbox.c
index 46b2304..b19f482 100644
--- a/dlls/comctl32/listbox.c
+++ b/dlls/comctl32/listbox.c
@@ -18,8 +18,6 @@
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
*
- * TODO:
- * - LBS_NODATA for multi-selection listboxes
*/
#include <string.h>
@@ -71,7 +69,11 @@ typedef struct
UINT style; /* Window style */
INT width; /* Window width */
INT height; /* Window height */
- LB_ITEMDATA *items; /* Array of items */
+ union
+ {
+ LB_ITEMDATA *items; /* Array of items */
+ BYTE *items_nodata; /* For multi-selection LBS_NODATA */
+ } u;
INT nb_items; /* Number of items */
UINT items_size; /* Total number of allocated items in the array */
INT top_item; /* Top visible item */
@@ -127,9 +129,19 @@ static TIMER_DIRECTION LISTBOX_Timer = LB_TIMER_NONE;
static LRESULT LISTBOX_GetItemRect( const LB_DESCR *descr, INT index, RECT *rect );
+/*
+ For listboxes without LBS_NODATA, an array of LB_ITEMDATA is allocated
+ to store the states of each item into descr->u.items.
+
+ For single-selection LBS_NODATA listboxes, no storage is allocated,
+ and thus descr->u.items_nodata will always be NULL.
+
+ For multi-selection LBS_NODATA listboxes, one byte per item is stored
+ for the item's selection state into descr->u.items_nodata.
+*/
static size_t get_item_size( const LB_DESCR *descr )
{
- return sizeof(LB_ITEMDATA);
+ return (descr->style & LBS_NODATA) ? sizeof(BYTE) : sizeof(LB_ITEMDATA);
}
static BOOL resize_storage(LB_DESCR *descr, UINT items_size)
@@ -142,20 +154,20 @@ static BOOL resize_storage(LB_DESCR *descr, UINT items_size)
items_size = (items_size + LB_ARRAY_GRANULARITY - 1) & ~(LB_ARRAY_GRANULARITY - 1);
if ((descr->style & (LBS_NODATA | LBS_MULTIPLESEL | LBS_EXTENDEDSEL)) != LBS_NODATA)
{
- items = heap_realloc(descr->items, items_size * get_item_size(descr));
+ items = heap_realloc(descr->u.items, items_size * get_item_size(descr));
if (!items)
{
SEND_NOTIFICATION(descr, LBN_ERRSPACE);
return FALSE;
}
- descr->items = items;
+ descr->u.items = items;
}
descr->items_size = items_size;
}
- if ((descr->style & LBS_NODATA) && descr->items && items_size > descr->nb_items)
+ if ((descr->style & LBS_NODATA) && descr->u.items_nodata && items_size > descr->nb_items)
{
- memset(&descr->items[descr->nb_items], 0,
+ memset(&descr->u.items_nodata[descr->nb_items], 0,
(items_size - descr->nb_items) * get_item_size(descr));
}
return TRUE;
@@ -163,67 +175,81 @@ static BOOL resize_storage(LB_DESCR *descr, UINT items_size)
static ULONG_PTR get_item_data( const LB_DESCR *descr, UINT index )
{
- return (descr->style & LBS_NODATA) ? 0 : descr->items[index].data;
+ return (descr->style & LBS_NODATA) ? 0 : descr->u.items[index].data;
}
static void set_item_data( LB_DESCR *descr, UINT index, ULONG_PTR data )
{
- if (!(descr->style & LBS_NODATA)) descr->items[index].data = data;
+ if (!(descr->style & LBS_NODATA)) descr->u.items[index].data = data;
}
static WCHAR *get_item_string( const LB_DESCR *descr, UINT index )
{
- return HAS_STRINGS(descr) ? descr->items[index].str : NULL;
+ return HAS_STRINGS(descr) ? descr->u.items[index].str : NULL;
}
static UINT get_item_height( const LB_DESCR *descr, UINT index )
{
- return (descr->style & LBS_NODATA) ? 0 : descr->items[index].height;
+ return (descr->style & LBS_NODATA) ? 0 : descr->u.items[index].height;
}
static void set_item_height( LB_DESCR *descr, UINT index, UINT height )
{
- if (!(descr->style & LBS_NODATA)) descr->items[index].height = height;
+ if (!(descr->style & LBS_NODATA)) descr->u.items[index].height = height;
}
static BOOL is_item_selected( const LB_DESCR *descr, UINT index )
{
if (!(descr->style & (LBS_MULTIPLESEL | LBS_EXTENDEDSEL)))
return index == descr->selected_item;
- return descr->items[index].selected;
+ if (descr->style & LBS_NODATA)
+ return descr->u.items_nodata[index];
+ else
+ return descr->u.items[index].selected;
}
static void set_item_selected_state(LB_DESCR *descr, UINT index, BOOL state)
{
if (descr->style & (LBS_MULTIPLESEL | LBS_EXTENDEDSEL))
- descr->items[index].selected = state;
+ {
+ if (descr->style & LBS_NODATA)
+ descr->u.items_nodata[index] = state;
+ else
+ descr->u.items[index].selected = state;
+ }
}
static void insert_item_data(LB_DESCR *descr, UINT index, WCHAR *str, ULONG_PTR data)
{
- LB_ITEMDATA *item;
+ size_t size = get_item_size(descr);
+ BYTE *p = descr->u.items_nodata + index * size;
- if (!descr->items) return;
+ if (!descr->u.items) return;
- item = descr->items + index;
if (index < descr->nb_items)
- memmove(item + 1, item, (descr->nb_items - index) * get_item_size(descr));
+ memmove(p + size, p, (descr->nb_items - index) * size);
- item->str = str;
- item->data = HAS_STRINGS(descr) ? 0 : data;
- item->height = 0;
- item->selected = FALSE;
+ if (descr->style & LBS_NODATA)
+ descr->u.items_nodata[index] = FALSE;
+ else
+ {
+ LB_ITEMDATA *item = descr->u.items + index;
+ item->str = str;
+ item->data = HAS_STRINGS(descr) ? 0 : data;
+ item->height = 0;
+ item->selected = FALSE;
+ }
}
static void remove_item_data(LB_DESCR *descr, UINT index)
{
- LB_ITEMDATA *item;
+ size_t size = get_item_size(descr);
+ BYTE *p = descr->u.items_nodata + index * size;
- if (!descr->items) return;
+ if (!descr->u.items) return;
- item = descr->items + index;
if (index < descr->nb_items)
- memmove(item, item + 1, (descr->nb_items - index) * get_item_size(descr));
+ memmove(p, p + size, (descr->nb_items - index) * size);
}
/***********************************************************************
@@ -1776,14 +1802,14 @@ static void LISTBOX_ResetContent( LB_DESCR *descr )
if (!(descr->style & LBS_NODATA))
for (i = descr->nb_items - 1; i >= 0; i--) LISTBOX_DeleteItem(descr, i);
- HeapFree( GetProcessHeap(), 0, descr->items );
+ HeapFree( GetProcessHeap(), 0, descr->u.items );
descr->nb_items = 0;
descr->top_item = 0;
descr->selected_item = -1;
descr->focus_item = 0;
descr->anchor_item = -1;
descr->items_size = 0;
- descr->items = NULL;
+ descr->u.items = NULL;
}
@@ -2530,7 +2556,7 @@ static BOOL LISTBOX_Create( HWND hwnd, LPHEADCOMBO lphc )
descr->style = GetWindowLongW( descr->self, GWL_STYLE );
descr->width = rect.right - rect.left;
descr->height = rect.bottom - rect.top;
- descr->items = NULL;
+ descr->u.items = NULL;
descr->items_size = 0;
descr->nb_items = 0;
descr->top_item = 0;
--
2.20.1
More information about the wine-devel
mailing list