+// we hook into WndProc to process WM_MOUSEMOVE/WM_BUTTONUP messages - as we
+// only do it during dragging, minimize wxWin overhead (this is important for
+// WM_MOUSEMOVE as they're a lot of them) by catching Windows messages directly
+// instead of passing by wxWin events
+WXLRESULT
+wxTreeCtrl::MSWWindowProc(WXUINT nMsg, WXWPARAM wParam, WXLPARAM lParam)
+{
+ bool processed = false;
+ WXLRESULT rc = 0;
+ bool isMultiple = HasFlag(wxTR_MULTIPLE);
+
+ if ( nMsg == WM_CONTEXTMENU )
+ {
+ int x = GET_X_LPARAM(lParam),
+ y = GET_Y_LPARAM(lParam);
+
+ // the item for which the menu should be shown
+ wxTreeItemId item;
+
+ // the position where the menu should be shown in client coordinates
+ // (so that it can be passed directly to PopupMenu())
+ wxPoint pt;
+
+ if ( x == -1 || y == -1 )
+ {
+ // this means that the event was generated from keyboard (e.g. with
+ // Shift-F10 or special Windows menu key)
+ //
+ // use the Explorer standard of putting the menu at the left edge
+ // of the text, in the vertical middle of the text
+ item = wxTreeItemId(TreeView_GetSelection(GetHwnd()));
+ if ( item.IsOk() )
+ {
+ // Use the bounding rectangle of only the text part
+ wxRect rect;
+ GetBoundingRect(item, rect, true);
+ pt = wxPoint(rect.GetX(), rect.GetY() + rect.GetHeight() / 2);
+ }
+ }
+ else // event from mouse, use mouse position
+ {
+ pt = ScreenToClient(wxPoint(x, y));
+
+ TV_HITTESTINFO tvhti;
+ tvhti.pt.x = pt.x;
+ tvhti.pt.y = pt.y;
+
+ if ( TreeView_HitTest(GetHwnd(), &tvhti) )
+ item = wxTreeItemId(tvhti.hItem);
+ }
+
+ // create the event
+ wxTreeEvent event(wxEVT_COMMAND_TREE_ITEM_MENU, this, item);
+
+ event.m_pointDrag = pt;
+
+ if ( HandleTreeEvent(event) )
+ processed = true;
+ //else: continue with generating wxEVT_CONTEXT_MENU in base class code
+ }
+ else if ( (nMsg >= WM_MOUSEFIRST) && (nMsg <= WM_MOUSELAST) )
+ {
+ // we only process mouse messages here and these parameters have the
+ // same meaning for all of them
+ int x = GET_X_LPARAM(lParam),
+ y = GET_Y_LPARAM(lParam);
+
+ TV_HITTESTINFO tvht;
+ tvht.pt.x = x;
+ tvht.pt.y = y;
+
+ HTREEITEM htOldItem = TreeView_GetSelection(GetHwnd());
+ HTREEITEM htItem = TreeView_HitTest(GetHwnd(), &tvht);
+
+ switch ( nMsg )
+ {
+ case WM_LBUTTONDOWN:
+ if ( !isMultiple )
+ break;
+
+ m_htClickedItem.Unset();
+
+ if ( !MSWIsOnItem(tvht.flags) )
+ {
+ if ( tvht.flags & TVHT_ONITEMBUTTON )
+ {
+ // either it's going to be handled by user code or
+ // we're going to use it ourselves to toggle the
+ // branch, in either case don't pass it to the base
+ // class which would generate another mouse click event
+ // for it even though it's already handled here
+ processed = true;
+ SetFocus();
+
+ if ( !HandleMouseEvent(nMsg, x, y, wParam) )
+ {
+ if ( !IsExpanded(htItem) )