From 50b4688c7eaf5db706fc019eb06c841affd37748 Mon Sep 17 00:00:00 2001 From: "Dimitrie O. Paun" Date: Tue, 15 Oct 2002 21:01:57 +0000 Subject: [PATCH] Iterator updates: Add the notion of a special item which sits at the start of the list. Add the ability to iterate in both directions through the list. Document the iterator interface. Remove iterator_visibleitems. Rename iterator_clippeditems to iterator_visibleitems for consistency. Use the new bidirectionality to paint the items in decreasing order. --- dlls/comctl32/listview.c | 179 ++++++++++++++++++++++++++++++++------- 1 file changed, 150 insertions(+), 29 deletions(-) diff --git a/dlls/comctl32/listview.c b/dlls/comctl32/listview.c index b50ac1a8356..4f2a7c83361 100644 --- a/dlls/comctl32/listview.c +++ b/dlls/comctl32/listview.c @@ -51,9 +51,6 @@ * these differences cause problems): * LVM_INSERTITEM issues LVM_SETITEMSTATE and LVM_SETITEM in certain cases. * LVM_SETITEM does not always issue LVN_ITEMCHANGING/LVN_ITEMCHANGED. - * WM_PAINT does LVN_GETDISPINFO in item order 0->n, native does n->0. - * WM_SETREDRAW(True) native does LVN_GETDISPINFO for all items and - * does *not* invoke DefWindowProc * WM_CREATE does not issue WM_QUERYUISTATE and associated registry * processing for "USEDOUBLECLICKTIME". */ @@ -112,6 +109,7 @@ typedef struct tagRANGE typedef struct tagITERATOR { INT nItem; + INT nSpecial; RANGE range; HDPA ranges; INT index; @@ -712,27 +710,143 @@ static BOOL ranges_add(HDPA ranges, RANGE range); static BOOL ranges_del(HDPA ranges, RANGE range); static void ranges_dump(HDPA ranges); +/*** + * ITERATOR DOCUMENTATION + * + * The iterator functions allow for easy, and convenient iteration + * over items of iterest in the list. Typically, you create a + * iterator, use it, and destroy it, as such: + * ITERATOR i; + * + * iterator_xxxitems(&i, ...); + * while (iterator_{prev,next}(&i) + * { + * //code which uses i.nItem + * } + * iterator_destroy(&i); + * + * where xxx is either: framed, or visible. + * Note that it is important that the code destroys the iterator + * after it's done with it, as the creation of the iterator may + * allocate memory, which thus needs to be freed. + * + * You can iterate both forwards, and backwards through the list, + * by using iterator_next or iterator_prev respectively. + * + * Lower numbered items are draw on top of higher number items in + * LVS_ICON, and LVS_SMALLICON (which are the only modes where + * items may overlap). So, to test items, you should use + * iterator_next + * which lists the items top to bottom (in Z-order). + * For drawing items, you should use + * iterator_prev + * which lists the items bottom to top (in Z-order). + * If you keep iterating over the items after the end-of-items + * marker (-1) is returned, the iterator will start from the + * beginning. Typically, you don't need to test for -1, + * because iterator_{next,prev} will return TRUE if more items + * are to be iterated over, or FALSE otherwise. + * + * Note: the iterator is defined to be bidirectional. That is, + * any number of prev followed by any number of next, or + * five versa, should leave the iterator at the same item: + * prev * n, next * n = next * n, prev * n + * + * The iterator has a notion of a out-of-order, special item, + * which sits at the start of the list. This is used in + * LVS_ICON, and LVS_SMALLICON mode to handle the focused item, + * which needs to be first, as it may overlap other items. + * + * The code is a bit messy because we have: + * - a special item to deal with + * - simple range, or composite range + * - empty range. + * If find bugs, or want to add features, please make sure you + * always check/modify *both* iterator_prev, and iterator_next. + */ + +/**** + * This function iterates through the items in increasing order, + * but prefixed by the special item, then -1. That is: + * special, 1, 2, 3, ..., n, -1. + * Each item is listed only once. + */ static inline BOOL iterator_next(ITERATOR* i) { if (i->nItem == -1) { - if (i->ranges) goto pickarange; - return (i->nItem = i->range.lower) != -1; + i->nItem = i->nSpecial; + if (i->nItem != -1) return TRUE; } + if (i->nItem == i->nSpecial) + { + if (i->ranges) i->index = 0; + goto pickarange; + } + i->nItem++; - if (i->nItem <= i->range.upper) - return TRUE; +testitem: + if (i->nItem == i->nSpecial) i->nItem++; + if (i->nItem <= i->range.upper) return TRUE; pickarange: - if (i->ranges && i->index < i->ranges->nItemCount) + if (i->ranges) { - i->range = *(RANGE*)DPA_GetPtr(i->ranges, i->index++); - return (i->nItem = i->range.lower) != -1; + if (i->index < i->ranges->nItemCount) + i->range = *(RANGE*)DPA_GetPtr(i->ranges, i->index++); + else goto end; } - i->nItem = i->range.lower = i->range.upper = -1; + else if (i->nItem > i->range.upper) goto end; + + i->nItem = i->range.lower; + if (i->nItem >= 0) goto testitem; +end: + i->nItem = -1; return FALSE; } +/**** + * This function iterates through the items in decreasing order, + * followed by the special item, then -1. That is: + * n, n-1, ..., 3, 2, 1, special, -1. + * Each item is listed only once. + */ +static inline BOOL iterator_prev(ITERATOR* i) +{ + BOOL start = FALSE; + + if (i->nItem == -1) + { + start = TRUE; + if (i->ranges) i->index = i->ranges->nItemCount; + goto pickarange; + } + if (i->nItem == i->nSpecial) + { + i->nItem = -1; + return FALSE; + } + + i->nItem--; +testitem: + if (i->nItem == i->nSpecial) i->nItem--; + if (i->nItem >= i->range.lower) return TRUE; + +pickarange: + if (i->ranges) + { + if (i->index > 0) + i->range = *(RANGE*)DPA_GetPtr(i->ranges, --i->index); + else goto end; + } + else if (!start && i->nItem < i->range.lower) goto end; + + i->nItem = i->range.upper; + if (i->nItem >= 0) goto testitem; +end: + return (i->nItem = i->nSpecial) != -1; +} + static RANGE iterator_range(ITERATOR* i) { RANGE range; @@ -744,18 +858,27 @@ static RANGE iterator_range(ITERATOR* i) return range; } +/*** + * Releases resources associated with this ierator. + */ static inline void iterator_destroy(ITERATOR* i) { if (i->ranges) DPA_Destroy(i->ranges); } +/*** + * Create an empty iterator. + */ static inline BOOL iterator_empty(ITERATOR* i) { ZeroMemory(i, sizeof(*i)); - i->nItem = i->range.lower = i->range.upper = -1; + i->nItem = i->nSpecial = i->range.lower = i->range.upper = -1; return TRUE; } +/*** + * Creates an iterator over the items which intersect lprc. + */ static BOOL iterator_frameditems(ITERATOR* i, LISTVIEW_INFO* infoPtr, const RECT* lprc) { UINT uView = infoPtr->dwStyle & LVS_TYPEMASK; @@ -803,7 +926,10 @@ static BOOL iterator_frameditems(ITERATOR* i, LISTVIEW_INFO* infoPtr, const RECT return TRUE; } -static BOOL iterator_clippeditems(ITERATOR* i, LISTVIEW_INFO *infoPtr, HDC hdc) +/*** + * Creates an iterator over the items which intersect the visible region of hdc. + */ +static BOOL iterator_visibleitems(ITERATOR* i, LISTVIEW_INFO *infoPtr, HDC hdc) { POINT Origin, Position; RECT rcItem, rcClip; @@ -814,7 +940,7 @@ static BOOL iterator_clippeditems(ITERATOR* i, LISTVIEW_INFO *infoPtr, HDC hdc) if (!iterator_frameditems(i, infoPtr, &rcClip)) return FALSE; if (rgntype == SIMPLEREGION) return TRUE; - /* if we can't deal with the region, we'll just go with the simple range */ + /* if we can't deal with the region, we'll just go with the simple range */ if (!LISTVIEW_GetOrigin(infoPtr, &Origin)) return TRUE; if (!(i->ranges = DPA_Create(10))) return TRUE; if (!ranges_add(i->ranges, i->range)) @@ -824,7 +950,7 @@ static BOOL iterator_clippeditems(ITERATOR* i, LISTVIEW_INFO *infoPtr, HDC hdc) return TRUE; } - /* no delete the invisible items from the list */ + /* now delete the invisible items from the list */ for (nItem = i->range.lower; nItem <= i->range.upper; nItem++) { if (!LISTVIEW_GetItemListOrigin(infoPtr, nItem, &Position)) continue; @@ -842,11 +968,6 @@ static BOOL iterator_clippeditems(ITERATOR* i, LISTVIEW_INFO *infoPtr, HDC hdc) return TRUE; } -static inline BOOL iterator_visibleitems(ITERATOR* i, LISTVIEW_INFO *infoPtr) -{ - return iterator_frameditems(i, infoPtr, &infoPtr->rcList); -} - /******** Misc helper functions ************************************/ static inline LRESULT CallWindowProcT(WNDPROC proc, HWND hwnd, UINT uMsg, @@ -1281,7 +1402,7 @@ static void LISTVIEW_InvalidateSelectedItems(LISTVIEW_INFO *infoPtr) { ITERATOR i; - iterator_visibleitems(&i, infoPtr); + iterator_frameditems(&i, infoPtr, &infoPtr->rcList); while(iterator_next(&i)) { if (LISTVIEW_GetItemState(infoPtr, i.nItem, LVIS_SELECTED)) @@ -3238,7 +3359,7 @@ static void LISTVIEW_RefreshOwnerDraw(LISTVIEW_INFO *infoPtr, HDC hdc) if (!LISTVIEW_GetOrigin(infoPtr, &Origin)) return; /* figure out what we need to draw */ - iterator_clippeditems(&i, infoPtr, hdc); + iterator_visibleitems(&i, infoPtr, hdc); /* send cache hint notification */ if (infoPtr->dwStyle & LVS_OWNERDATA) @@ -3252,7 +3373,7 @@ static void LISTVIEW_RefreshOwnerDraw(LISTVIEW_INFO *infoPtr, HDC hdc) } /* iterate through the invalidated rows */ - while(iterator_next(&i)) + while(iterator_prev(&i)) { item.iItem = i.nItem; item.iSubItem = 0; @@ -3344,13 +3465,13 @@ static void LISTVIEW_RefreshReport(LISTVIEW_INFO *infoPtr, HDC hdc, DWORD cdmode } /* figure out what we need to draw */ - iterator_clippeditems(&i, infoPtr, hdc); + iterator_visibleitems(&i, infoPtr, hdc); /* a last few bits before we start drawing */ TRACE("Colums=(%di - %d)\n", nFirstCol, nLastCol); /* iterate through the invalidated rows */ - while(iterator_next(&i)) + while(iterator_prev(&i)) { nDrawPosY = i.nItem * infoPtr->nItemHeight; @@ -3404,9 +3525,9 @@ static void LISTVIEW_RefreshList(LISTVIEW_INFO *infoPtr, HDC hdc, DWORD cdmode) if (!LISTVIEW_GetOrigin(infoPtr, &Origin)) return; /* figure out what we need to draw */ - iterator_clippeditems(&i, infoPtr, hdc); + iterator_visibleitems(&i, infoPtr, hdc); - while(iterator_next(&i)) + while(iterator_prev(&i)) { if (!LISTVIEW_GetItemListOrigin(infoPtr, i.nItem, &Position)) continue; Position.x += Origin.x; @@ -3439,9 +3560,9 @@ static void LISTVIEW_RefreshIcon(LISTVIEW_INFO *infoPtr, HDC hdc, DWORD cdmode) if (!LISTVIEW_GetOrigin(infoPtr, &Origin)) return; /* figure out what we need to draw */ - iterator_clippeditems(&i, infoPtr, hdc); + iterator_visibleitems(&i, infoPtr, hdc); - while(iterator_next(&i)) + while(iterator_prev(&i)) { if (LISTVIEW_GetItemState(infoPtr, i.nItem, LVIS_FOCUSED)) continue;