dlls/comctl32/draglist.c

   1 /*
   2  * Drag List control
   3  *
   4  * Copyright 1999 Eric Kohl
   5  * Copyright 2004 Robert Shearman
   6  *
   7  * This library is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * This library is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with this library; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  20  *
  21  * NOTES
  22  *
  23  * This code was audited for completeness against the documented features
  24  * of Comctl32.dll version 6.0 on Mar. 10, 2004, by Robert Shearman.
  25  *
  26  * Unless otherwise noted, we believe this code to be complete, as per
  27  * the specification mentioned above.
  28  * If you discover missing features or bugs please note them below.
  29  *
  30  */
  31
  32 #include <stdarg.h>
  33
  34 #include "windef.h"
  35 #include "winbase.h"
  36 #include "wingdi.h"
  37 #include "winuser.h"
  38 #include "winnls.h"
  39 #include "commctrl.h"
  40 #include "comctl32.h"
  41 #include "wine/debug.h"
  42
  43 WINE_DEFAULT_DEBUG_CHANNEL(commctrl);
  44
  45 #define DRAGLIST_SUBCLASSID     0
  46 #define DRAGLIST_SCROLLPERIOD 200
  47 #define DRAGLIST_TIMERID      666
  48
  49 /* properties relating to IDI_DRAGICON */
  50 #define DRAGICON_HOTSPOT_X 17
  51 #define DRAGICON_HOTSPOT_Y  7
  52 #define DRAGICON_HEIGHT    32
  53
  54 /* internal Wine specific data for the drag list control */
  55 typedef struct _DRAGLISTDATA
  56 {
  57     /* are we currently in dragging mode? */
  58     BOOL dragging;
  59
  60     /* cursor to use as determined by DL_DRAGGING notification.
  61      * NOTE: as we use LoadCursor we don't have to use DeleteCursor
  62      * when we are finished with it */
  63     HCURSOR cursor;
  64
  65     /* optimisation so that we don't have to load the cursor
  66      * all of the time whilst dragging */
  67     LRESULT last_dragging_response;
  68
  69     /* prevents flicker with drawing drag arrow */
  70     RECT last_drag_icon_rect;
  71 } DRAGLISTDATA;
  72
  73 UINT uDragListMessage = 0; /* registered window message code */
  74 static DWORD dwLastScrollTime = 0;
  75 static HICON hDragArrow = NULL;
  76
  77 /***********************************************************************
  78  *              DragList_Notify (internal)
  79  *
  80  * Sends notification messages to the parent control. Note that it
  81  * does not use WM_NOTIFY like the rest of the controls, but a registered
  82  * window message.
  83  */
  84 static LRESULT DragList_Notify(HWND hwndLB, UINT uNotification)
  85 {
  86     DRAGLISTINFO dli;
  87     dli.hWnd = hwndLB;
  88     dli.uNotification = uNotification;
  89     GetCursorPos(&dli.ptCursor);
  90     return SendMessageW(GetParent(hwndLB), uDragListMessage, GetDlgCtrlID(hwndLB), (LPARAM)&dli);
  91 }
  92
  93 /* cleans up after dragging */
  94 static void DragList_EndDrag(HWND hwnd, DRAGLISTDATA * data)
  95 {
  96     KillTimer(hwnd, DRAGLIST_TIMERID);
  97     ReleaseCapture();
  98     /* clear any drag insert icon present */
  99     InvalidateRect(GetParent(hwnd), &data->last_drag_icon_rect, TRUE);
 100     /* clear data for next use */
 101     memset(data, 0, sizeof(*data));
 102 }
 103
 104 /***********************************************************************
 105  *              DragList_SubclassWindowProc (internal)
 106  *
 107  * Handles certain messages to enable dragging for the ListBox and forwards
 108  * the rest to the ListBox.
 109  */
 110 static LRESULT CALLBACK
 111 DragList_SubclassWindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam, UINT_PTR uIdSubclass, DWORD_PTR dwRefData)
 112 {
 113     DRAGLISTDATA * data = (DRAGLISTDATA*)dwRefData;
 114     switch (uMsg)
 115     {
 116     case WM_LBUTTONDOWN:
 117         SetFocus(hwnd);
 118         data->dragging = DragList_Notify(hwnd, DL_BEGINDRAG);
 119         if (data->dragging)
 120         {
 121             SetCapture(hwnd);
 122             SetTimer(hwnd, DRAGLIST_TIMERID, DRAGLIST_SCROLLPERIOD, NULL);
 123         }
 124         /* note that we don't absorb this message to let the list box
 125          * do its thing (normally selecting an item) */
 126         break;
 127
 128     case WM_KEYDOWN:
 129     case WM_RBUTTONDOWN:
 130         /* user cancelled drag by either right clicking or
 131          * by pressing the escape key */
 132         if ((data->dragging) &&
 133             ((uMsg == WM_RBUTTONDOWN) || (wParam == VK_ESCAPE)))
 134         {
 135             /* clean up and absorb message */
 136             DragList_EndDrag(hwnd, data);
 137             DragList_Notify(hwnd, DL_CANCELDRAG);
 138             return 0;
 139         }
 140         break;
 141
 142     case WM_MOUSEMOVE:
 143     case WM_TIMER:
 144         if (data->dragging)
 145         {
 146             LRESULT cursor = DragList_Notify(hwnd, DL_DRAGGING);
 147             /* optimisation so that we don't have to load the cursor
 148              * all of the time whilst dragging */
 149             if (data->last_dragging_response != cursor)
 150             {
 151                 switch (cursor)
 152                 {
 153                 case DL_STOPCURSOR:
 154                     data->cursor = LoadCursorW(NULL, (LPCWSTR)IDC_NO);
 155                     SetCursor(data->cursor);
 156                     break;
 157                 case DL_COPYCURSOR:
 158                     data->cursor = LoadCursorW(COMCTL32_hModule, (LPCWSTR)IDC_COPY);
 159                     SetCursor(data->cursor);
 160                     break;
 161                 case DL_MOVECURSOR:
 162                     data->cursor = LoadCursorW(NULL, (LPCWSTR)IDC_ARROW);
 163                     SetCursor(data->cursor);
 164                     break;
 165                 }
 166                 data->last_dragging_response = cursor;
 167             }
 168             /* don't pass this message on to List Box */
 169             return 0;
 170         }
 171         break;
 172
 173     case WM_LBUTTONUP:
 174         if (data->dragging)
 175         {
 176             DragList_EndDrag(hwnd, data);
 177             DragList_Notify(hwnd, DL_DROPPED);
 178         }
 179         break;
 180
 181     case WM_GETDLGCODE:
 182         /* tell dialog boxes that we want to receive WM_KEYDOWN events
 183          * for keys like VK_ESCAPE */
 184         if (data->dragging)
 185             return DLGC_WANTALLKEYS;
 186         break;
 187     case WM_NCDESTROY:
 188         RemoveWindowSubclass(hwnd, DragList_SubclassWindowProc, DRAGLIST_SUBCLASSID);
 189         Free(data);
 190         break;
 191     }
 192     return DefSubclassProc(hwnd, uMsg, wParam, lParam);
 193 }
 194
 195 /***********************************************************************
 196  *              MakeDragList (COMCTL32.13)
 197  *
 198  * Makes a normal ListBox into a DragList by subclassing it.
 199  *
 200  * RETURNS
 201  *      Success: Non-zero
 202  *      Failure: Zero
 203  */
 204 BOOL WINAPI MakeDragList (HWND hwndLB)
 205 {
 206     DRAGLISTDATA *data = Alloc(sizeof(DRAGLISTDATA));
 207
 208     TRACE("(%p)\n", hwndLB);
 209
 210     if (!uDragListMessage)
 211         uDragListMessage = RegisterWindowMessageW(DRAGLISTMSGSTRINGW);
 212
 213     return SetWindowSubclass(hwndLB, DragList_SubclassWindowProc, DRAGLIST_SUBCLASSID, (DWORD_PTR)data);
 214 }
 215
 216 /***********************************************************************
 217  *              DrawInsert (COMCTL32.15)
 218  *
 219  * Draws insert arrow by the side of the ListBox item in the parent window.
 220  *
 221  * RETURNS
 222  *      Nothing.
 223  */
 224 VOID WINAPI DrawInsert (HWND hwndParent, HWND hwndLB, INT nItem)
 225 {
 226     RECT rcItem, rcListBox, rcDragIcon;
 227     HDC hdc;
 228     DRAGLISTDATA * data;
 229
 230     TRACE("(%p %p %d)\n", hwndParent, hwndLB, nItem);
 231
 232     if (!hDragArrow)
 233         hDragArrow = LoadIconW(COMCTL32_hModule, (LPCWSTR)IDI_DRAGARROW);
 234
 235     if (LB_ERR == SendMessageW(hwndLB, LB_GETITEMRECT, nItem, (LPARAM)&rcItem))
 236         return;
 237
 238     if (!GetWindowRect(hwndLB, &rcListBox))
 239         return;
 240
 241     /* convert item rect to parent co-ordinates */
 242     if (!MapWindowPoints(hwndLB, hwndParent, (LPPOINT)&rcItem, 2))
 243         return;
 244
 245     /* convert list box rect to parent co-ordinates */
 246     if (!MapWindowPoints(HWND_DESKTOP, hwndParent, (LPPOINT)&rcListBox, 2))
 247         return;
 248
 249     rcDragIcon.left = rcListBox.left - DRAGICON_HOTSPOT_X;
 250     rcDragIcon.top = rcItem.top - DRAGICON_HOTSPOT_Y;
 251     rcDragIcon.right = rcListBox.left;
 252     rcDragIcon.bottom = rcDragIcon.top + DRAGICON_HEIGHT;
 253
 254     if (!GetWindowSubclass(hwndLB, DragList_SubclassWindowProc, DRAGLIST_SUBCLASSID, (DWORD_PTR*)&data))
 255         return;
 256
 257     if (nItem < 0)
 258         SetRectEmpty(&rcDragIcon);
 259
 260     /* prevent flicker by only redrawing when necessary */
 261     if (!EqualRect(&rcDragIcon, &data->last_drag_icon_rect))
 262     {
 263         /* get rid of any previous inserts drawn */
 264         RedrawWindow(hwndParent, &data->last_drag_icon_rect, NULL,
 265             RDW_INTERNALPAINT | RDW_ERASE | RDW_INVALIDATE | RDW_UPDATENOW);
 266
 267         CopyRect(&data->last_drag_icon_rect, &rcDragIcon);
 268
 269         if (nItem >= 0)
 270         {
 271             hdc = GetDC(hwndParent);
 272
 273             DrawIcon(hdc, rcDragIcon.left, rcDragIcon.top, hDragArrow);
 274
 275             ReleaseDC(hwndParent, hdc);
 276         }
 277     }
 278 }
 279
 280 /***********************************************************************
 281  *              LBItemFromPt (COMCTL32.14)
 282  *
 283  * Gets the index of the ListBox item under the specified point,
 284  * scrolling if bAutoScroll is TRUE and pt is outside of the ListBox.
 285  *
 286  * RETURNS
 287  *      The ListBox item ID if pt is over a list item or -1 otherwise.
 288  */
 289 INT WINAPI LBItemFromPt (HWND hwndLB, POINT pt, BOOL bAutoScroll)
 290 {
 291     RECT rcClient;
 292     INT nIndex;
 293     DWORD dwScrollTime;
 294
 295     TRACE("(%p %d x %d %s)\n",
 296            hwndLB, pt.x, pt.y, bAutoScroll ? "TRUE" : "FALSE");
 297
 298     ScreenToClient (hwndLB, &pt);
 299     GetClientRect (hwndLB, &rcClient);
 300     nIndex = (INT)SendMessageW (hwndLB, LB_GETTOPINDEX, 0, 0);
 301
 302     if (PtInRect (&rcClient, pt))
 303     {
 304         /* point is inside -- get the item index */
 305         while (TRUE)
 306         {
 307             if (SendMessageW (hwndLB, LB_GETITEMRECT, nIndex, (LPARAM)&rcClient) == LB_ERR)
 308                 return -1;
 309
 310             if (PtInRect (&rcClient, pt))
 311                 return nIndex;
 312
 313             nIndex++;
 314         }
 315     }
 316     else
 317     {
 318         /* point is outside */
 319         if (!bAutoScroll)
 320             return -1;
 321
 322         if ((pt.x > rcClient.right) || (pt.x < rcClient.left))
 323             return -1;
 324
 325         if (pt.y < 0)
 326             nIndex--;
 327         else
 328             nIndex++;
 329
 330         dwScrollTime = GetTickCount ();
 331
 332         if ((dwScrollTime - dwLastScrollTime) < DRAGLIST_SCROLLPERIOD)
 333             return -1;
 334
 335         dwLastScrollTime = dwScrollTime;
 336
 337         SendMessageW (hwndLB, LB_SETTOPINDEX, (WPARAM)nIndex, 0);
 338     }
 339
 340     return -1;
 341 }