combo.c

来自「一个类似windows」· C语言 代码 · 共 2,183 行 · 第 1/5 页

   * Get the background brush for this control.
   */
  if (CB_DISABLED(lphc))
  {
    hBkgBrush = (HBRUSH)SendMessageW(lphc->owner, WM_CTLCOLORSTATIC,
				     (WPARAM)hDC, (LPARAM)lphc->self );

    /*
     * We have to change the text color since WM_CTLCOLORSTATIC will
     * set it to the "enabled" color. This is the same behavior as the
     * edit control
     */
    SetTextColor(hDC, GetSysColor(COLOR_GRAYTEXT));
  }
  else
  {
    if (lphc->wState & CBF_EDIT)
    {
      hBkgBrush = (HBRUSH)SendMessageW(lphc->owner, WM_CTLCOLOREDIT,
				       (WPARAM)hDC, (LPARAM)lphc->self );
    }
    else
    {
      hBkgBrush = (HBRUSH)SendMessageW(lphc->owner, WM_CTLCOLORLISTBOX,
				       (WPARAM)hDC, (LPARAM)lphc->self );
    }
  }

  /*
   * Catch errors.
   */
  if( !hBkgBrush )
    hBkgBrush = GetSysColorBrush(COLOR_WINDOW);

  return hBkgBrush;
}

/***********************************************************************
 *           COMBO_EraseBackground
 */
static LRESULT COMBO_EraseBackground(
  HWND        hwnd,
  LPHEADCOMBO lphc,
  HDC         hParamDC)
{
  HBRUSH  hBkgBrush;
  HDC 	  hDC;

  if(lphc->wState & CBF_EDIT)
      return TRUE;

  hDC = (hParamDC) ? hParamDC
		   : GetDC(hwnd);
  /*
   * Retrieve the background brush
   */
  hBkgBrush = COMBO_PrepareColors(lphc, hDC);

  FillRect(hDC, &lphc->textRect, hBkgBrush);

  if (!hParamDC)
    ReleaseDC(hwnd, hDC);

  return TRUE;
}

/***********************************************************************
 *           COMBO_Paint
 */
static LRESULT COMBO_Paint(LPHEADCOMBO lphc, HDC hParamDC)
{
  PAINTSTRUCT ps;
  HDC 	hDC;

  hDC = (hParamDC) ? hParamDC
		   : BeginPaint( lphc->self, &ps);

  TRACE("hdc=%p\n", hDC);

  if( hDC && !(lphc->wState & CBF_NOREDRAW) )
  {
      HBRUSH	hPrevBrush, hBkgBrush;

      /*
       * Retrieve the background brush and select it in the
       * DC.
       */
      hBkgBrush = COMBO_PrepareColors(lphc, hDC);

      hPrevBrush = SelectObject( hDC, hBkgBrush );

      /*
       * In non 3.1 look, there is a sunken border on the combobox
       */
      CBPaintBorder(lphc->self, lphc, hDC);

      if( !IsRectEmpty(&lphc->buttonRect) )
      {
	CBPaintButton(lphc, hDC, lphc->buttonRect);
      }

      /* paint the edit control padding area */
      if (CB_GETTYPE(lphc) != CBS_DROPDOWNLIST)
      {
          RECT rPadEdit = lphc->textRect;

          InflateRect(&rPadEdit, EDIT_CONTROL_PADDING(), EDIT_CONTROL_PADDING());

          FrameRect( hDC, &rPadEdit, GetSysColorBrush(COLOR_WINDOW) );
      }

      if( !(lphc->wState & CBF_EDIT) )
	CBPaintText( lphc, hDC, lphc->textRect);

      if( hPrevBrush )
	SelectObject( hDC, hPrevBrush );
  }

  if( !hParamDC )
    EndPaint(lphc->self, &ps);

  return 0;
}

/***********************************************************************
 *           CBUpdateLBox
 *
 * Select listbox entry according to the contents of the edit control.
 */
static INT CBUpdateLBox( LPHEADCOMBO lphc, BOOL bSelect )
{
   INT	length, idx;
   LPWSTR pText = NULL;

   idx = LB_ERR;
   length = SendMessageW( lphc->hWndEdit, WM_GETTEXTLENGTH, 0, 0 );

   if( length > 0 )
       pText = HeapAlloc( GetProcessHeap(), 0, (length + 1) * sizeof(WCHAR));

   TRACE("\t edit text length %i\n", length );

   if( pText )
   {
       if( length ) GetWindowTextW( lphc->hWndEdit, pText, length + 1);
       else pText[0] = '\0';
       idx = SendMessageW(lphc->hWndLBox, LB_FINDSTRING,
			     (WPARAM)(-1), (LPARAM)pText );
       HeapFree( GetProcessHeap(), 0, pText );
   }

   SendMessageW(lphc->hWndLBox, LB_SETCURSEL, (WPARAM)(bSelect ? idx : -1), 0);

   /* probably superfluous but Windows sends this too */
   SendMessageW(lphc->hWndLBox, LB_SETCARETINDEX, (WPARAM)(idx < 0 ? 0 : idx), 0);
   SendMessageW(lphc->hWndLBox, LB_SETTOPINDEX, (WPARAM)(idx < 0 ? 0 : idx), 0);

   return idx;
}

/***********************************************************************
 *           CBUpdateEdit
 *
 * Copy a listbox entry to the edit control.
 */
static void CBUpdateEdit( LPHEADCOMBO lphc , INT index )
{
   INT	length;
   LPWSTR pText = NULL;
   static const WCHAR empty_stringW[] = { 0 };

   TRACE("\t %i\n", index );

   if( index >= 0 ) /* got an entry */
   {
       length = SendMessageW(lphc->hWndLBox, LB_GETTEXTLEN, (WPARAM)index, 0);
       if( length != LB_ERR)
       {
	   if( (pText = HeapAlloc( GetProcessHeap(), 0, (length + 1) * sizeof(WCHAR))) )
	   {
		SendMessageW(lphc->hWndLBox, LB_GETTEXT,
				(WPARAM)index, (LPARAM)pText );
	   }
       }
   }

   lphc->wState |= (CBF_NOEDITNOTIFY | CBF_NOLBSELECT);
   SendMessageW(lphc->hWndEdit, WM_SETTEXT, 0, pText ? (LPARAM)pText : (LPARAM)empty_stringW);
   lphc->wState &= ~(CBF_NOEDITNOTIFY | CBF_NOLBSELECT);

   if( lphc->wState & CBF_FOCUSED )
      SendMessageW(lphc->hWndEdit, EM_SETSEL, 0, (LPARAM)(-1));

   HeapFree( GetProcessHeap(), 0, pText );
}

/***********************************************************************
 *           CBDropDown
 *
 * Show listbox popup.
 */
static void CBDropDown( LPHEADCOMBO lphc )
{
   RECT rect,r;
   int nItems = 0;
   int nDroppedHeight;

   TRACE("[%p]: drop down\n", lphc->self);

   CB_NOTIFY( lphc, CBN_DROPDOWN );

   /* set selection */

   lphc->wState |= CBF_DROPPED;
   if( CB_GETTYPE(lphc) == CBS_DROPDOWN )
   {
       lphc->droppedIndex = CBUpdateLBox( lphc, TRUE );

       /* Update edit only if item is in the list */
       if( !(lphc->wState & CBF_CAPTURE) && lphc->droppedIndex >= 0)
	 CBUpdateEdit( lphc, lphc->droppedIndex );
   }
   else
   {
       lphc->droppedIndex = SendMessageW(lphc->hWndLBox, LB_GETCURSEL, 0, 0);

       SendMessageW(lphc->hWndLBox, LB_SETTOPINDEX,
                     (WPARAM)(lphc->droppedIndex == LB_ERR ? 0 : lphc->droppedIndex), 0 );
       SendMessageW(lphc->hWndLBox, LB_CARETON, 0, 0);
   }

   /* now set popup position */
   GetWindowRect( lphc->self, &rect );

   /*
    * If it's a dropdown, the listbox is offset
    */
   if( CB_GETTYPE(lphc) == CBS_DROPDOWN )
     rect.left += COMBO_EDITBUTTONSPACE();

  /* if the dropped height is greater than the total height of the dropped
     items list, then force the drop down list height to be the total height
     of the items in the dropped list */

  /* And Remove any extra space (Best Fit) */
   nDroppedHeight = lphc->droppedRect.bottom - lphc->droppedRect.top;
  /* if listbox length has been set directly by its handle */
   GetWindowRect(lphc->hWndLBox, &r);
   if (nDroppedHeight < r.bottom - r.top)
       nDroppedHeight = r.bottom - r.top;
   nItems = (int)SendMessageW(lphc->hWndLBox, LB_GETCOUNT, 0, 0);

   if (nItems > 0)
   {
      int nHeight;
      int nIHeight;

      nIHeight = (int)SendMessageW(lphc->hWndLBox, LB_GETITEMHEIGHT, 0, 0);

      nHeight = nIHeight*nItems;

      if (nHeight < nDroppedHeight - COMBO_YBORDERSIZE())
         nDroppedHeight = nHeight + COMBO_YBORDERSIZE();

      if (nDroppedHeight < nIHeight)
      {
            if (nItems < 5)
                nDroppedHeight = (nItems+1)*nIHeight;
            else
                nDroppedHeight = 6*nIHeight;
      }
   }

   /*If height of dropped rectangle gets beyond a screen size it should go up, otherwise down.*/
   if( (rect.bottom + nDroppedHeight) >= GetSystemMetrics( SM_CYSCREEN ) )
      rect.bottom = rect.top - nDroppedHeight;

   SetWindowPos( lphc->hWndLBox, HWND_TOP, rect.left, rect.bottom,
		 lphc->droppedRect.right - lphc->droppedRect.left,
		 nDroppedHeight,
		 SWP_NOACTIVATE | SWP_SHOWWINDOW);


   if( !(lphc->wState & CBF_NOREDRAW) )
     RedrawWindow( lphc->self, NULL, 0, RDW_INVALIDATE |
			   RDW_ERASE | RDW_UPDATENOW | RDW_NOCHILDREN );

   EnableWindow( lphc->hWndLBox, TRUE );
   if (GetCapture() != lphc->self)
      SetCapture(lphc->hWndLBox);
}

/***********************************************************************
 *           CBRollUp
 *
 * Hide listbox popup.
 */
static void CBRollUp( LPHEADCOMBO lphc, BOOL ok, BOOL bButton )
{
   HWND	hWnd = lphc->self;

   TRACE("[%p]: sel ok? [%i] dropped? [%i]\n",
	 lphc->self, (INT)ok, (INT)(lphc->wState & CBF_DROPPED));

   CB_NOTIFY( lphc, (ok) ? CBN_SELENDOK : CBN_SELENDCANCEL );

   if( IsWindow( hWnd ) && CB_GETTYPE(lphc) != CBS_SIMPLE )
   {

       if( lphc->wState & CBF_DROPPED )
       {
	   RECT	rect;

	   lphc->wState &= ~CBF_DROPPED;
	   ShowWindow( lphc->hWndLBox, SW_HIDE );

           if(GetCapture() == lphc->hWndLBox)
           {
               ReleaseCapture();
           }

	   if( CB_GETTYPE(lphc) == CBS_DROPDOWN )
	   {
	       rect = lphc->buttonRect;
	   }
	   else
           {
	       if( bButton )
	       {
		 UnionRect( &rect,
			    &lphc->buttonRect,
			    &lphc->textRect);
	       }
	       else
		 rect = lphc->textRect;

	       bButton = TRUE;
	   }

	   if( bButton && !(lphc->wState & CBF_NOREDRAW) )
	       RedrawWindow( hWnd, &rect, 0, RDW_INVALIDATE |
			       RDW_ERASE | RDW_UPDATENOW | RDW_NOCHILDREN );
	   CB_NOTIFY( lphc, CBN_CLOSEUP );
       }
   }
}

/***********************************************************************
 *           COMBO_FlipListbox
 *
 * Used by the ComboLBox to show/hide itself in response to VK_F4, etc...
 */
BOOL COMBO_FlipListbox( LPHEADCOMBO lphc, BOOL ok, BOOL bRedrawButton )
{
   if( lphc->wState & CBF_DROPPED )
   {
       CBRollUp( lphc, ok, bRedrawButton );
       return FALSE;
   }

   CBDropDown( lphc );
   return TRUE;
}

/***********************************************************************
 *           CBRepaintButton
 */
static void CBRepaintButton( LPHEADCOMBO lphc )
   {
  InvalidateRect(lphc->self, &lphc->buttonRect, TRUE);
  UpdateWindow(lphc->self);
}

/***********************************************************************
 *           COMBO_SetFocus
 */
static void COMBO_SetFocus( LPHEADCOMBO lphc )
{
   if( !(lphc->wState & CBF_FOCUSED) )
   {
       if( CB_GETTYPE(lphc) == CBS_DROPDOWNLIST )
           SendMessageW(lphc->hWndLBox, LB_CARETON, 0, 0);

       /* This is wrong. Message sequences seem to indicate that this
          is set *after* the notify. */
       /* lphc->wState |= CBF_FOCUSED;  */

       if( !(lphc->wState & CBF_EDIT) )
	 InvalidateRect(lphc->self, &lphc->textRect, TRUE);

       CB_NOTIFY( lphc, CBN_SETFOCUS );
       lphc->wState |= CBF_FOCUSED;
   }
}

/***********************************************************************
 *           COMBO_KillFocus
 */
static void COMBO_KillFocus( LPHEADCOMBO lphc )
{
   HWND	hWnd = lphc->self;

   if( lphc->wState & CBF_FOCUSED )
   {
       CBRollUp( lphc, FALSE, TRUE );
       if( IsWindow( hWnd ) )
       {
           if( CB_GETTYPE(lphc) == CBS_DROPDOWNLIST )
               SendMessageW(lphc->hWndLBox, LB_CARETOFF, 0, 0);

 	   lphc->wState &= ~CBF_FOCUSED;

           /* redraw text */
	   if( !(lphc->wState & CBF_EDIT) )
	     InvalidateRect(lphc->self, &lphc->textRect, TRUE);

           CB_NOTIFY( lphc, CBN_KILLFOCUS );
       }
   }
}

/***********************************************************************
 *           COMBO_Command
 */
static LRESULT COMBO_Command( LPHEADCOMBO lphc, WPARAM wParam, HWND hWnd )
{
   if ( lphc->wState & CBF_EDIT && lphc->hWndEdit == hWnd )
   {
       /* ">> 8" makes gcc generate jump-table instead of cmp ladder */

       switch( HIWORD(wParam) >> 8 )
       {
	   case (EN_SETFOCUS >> 8):

               TRACE("[%p]: edit [%p] got focus\n", lphc->self, lphc->hWndEdit );

		COMBO_SetFocus( lphc );