X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/6719c06a978dcb50e2e7b156a4925aa9849a7589..d6f04127fe1b3a9008605b22419af78eba5ae857:/src/msw/treectrl.cpp

diff --git a/src/msw/treectrl.cpp b/src/msw/treectrl.cpp
index 63019b5e22..cbda527b0e 100644
--- a/src/msw/treectrl.cpp
+++ b/src/msw/treectrl.cpp
@@ -72,19 +72,38 @@ typedef struct tagNMTVITEMCHANGE
 #endif
 
 
-// this global variable is used on vista systems for preventing unwanted
-// item state changes in the vista tree control.  It is only used in
+// this helper class is used on vista systems for preventing unwanted
+// item state changes in the vista tree control.  It is only effective in
 // multi-select mode on vista systems.
 
-static HTREEITEM gs_unlockItem = NULL;
+// The vista tree control includes some new code that originally broke the
+// multi-selection tree, causing seemingly spurious item selection state changes
+// during Shift or Ctrl-click item selection. (To witness the original broken
+// behavior, simply make IsLocked() below always return false). This problem was
+// solved by using the following class to 'unlock' an item's selection state.
 
 class TreeItemUnlocker
 {
 public:
-    TreeItemUnlocker(HTREEITEM item) { gs_unlockItem = item; }
-    ~TreeItemUnlocker() { gs_unlockItem = NULL; }
+    // unlock a single item
+    TreeItemUnlocker(HTREEITEM item) { ms_unlockedItem = item; }
+
+    // unlock all items, don't use unless absolutely necessary
+    TreeItemUnlocker() { ms_unlockedItem = (HTREEITEM)-1; }
+
+    // lock everything back
+    ~TreeItemUnlocker() { ms_unlockedItem = NULL; }
+
+
+    // check if the item state is currently locked
+    static bool IsLocked(HTREEITEM item)
+        { return ms_unlockedItem != (HTREEITEM)-1 && item != ms_unlockedItem; }
+
+private:
+    static HTREEITEM ms_unlockedItem;
 };
 
+HTREEITEM TreeItemUnlocker::ms_unlockedItem = NULL;
 
 // ----------------------------------------------------------------------------
 // private functions
@@ -1586,6 +1605,10 @@ wxTreeItemId wxTreeCtrl::DoInsertItem(const wxTreeItemId& parent,
 
 void wxTreeCtrl::Delete(const wxTreeItemId& item)
 {
+    // unlock tree selections on vista, without this the
+    // tree ctrl will eventually crash after item deletion
+    TreeItemUnlocker unlock_all;
+
     if ( !TreeView_DeleteItem(GetHwnd(), HITEM(item)) )
     {
         wxLogLastError(wxT("TreeView_DeleteItem"));
@@ -1595,6 +1618,9 @@ void wxTreeCtrl::Delete(const wxTreeItemId& item)
 // delete all children (but don't delete the item itself)
 void wxTreeCtrl::DeleteChildren(const wxTreeItemId& item)
 {
+    // unlock tree selections on vista for the duration of this call
+    TreeItemUnlocker unlock_all;
+
     wxTreeItemIdValue cookie;
 
     wxArrayTreeItemIds children;
@@ -1618,6 +1644,9 @@ void wxTreeCtrl::DeleteChildren(const wxTreeItemId& item)
 
 void wxTreeCtrl::DeleteAllItems()
 {
+    // unlock tree selections on vista for the duration of this call
+    TreeItemUnlocker unlock_all;
+
     // delete the "virtual" root item.
     if ( GET_VIRTUAL_ROOT() )
     {
@@ -1665,7 +1694,7 @@ void wxTreeCtrl::DoExpand(const wxTreeItemId& item, int flag)
                                                            : IDX_COLLAPSE]
                                          [IDX_DONE],
                            this, item);
-        (void)GetEventHandler()->ProcessEvent(event);
+        (void)HandleWindowEvent(event);
     }
     //else: change didn't took place, so do nothing at all
 }
@@ -1727,7 +1756,7 @@ void wxTreeCtrl::SelectItem(const wxTreeItemId& item, bool select)
                   _T("SelectItem(false) works only for multiselect") );
 
     wxTreeEvent event(wxEVT_COMMAND_TREE_SEL_CHANGING, this, item);
-    if ( !GetEventHandler()->ProcessEvent(event) || event.IsAllowed() )
+    if ( !HandleWindowEvent(event) || event.IsAllowed() )
     {
         if ( HasFlag(wxTR_MULTIPLE) )
         {
@@ -1748,7 +1777,7 @@ void wxTreeCtrl::SelectItem(const wxTreeItemId& item, bool select)
         }
 
         event.SetEventType(wxEVT_COMMAND_TREE_SEL_CHANGED);
-        (void)GetEventHandler()->ProcessEvent(event);
+        (void)HandleWindowEvent(event);
     }
     //else: program vetoed the change
 }
@@ -2041,7 +2070,7 @@ WXLRESULT wxTreeCtrl::MSWWindowProc(WXUINT nMsg, WXWPARAM wParam, WXLPARAM lPara
 
         event.m_pointDrag = pt;
 
-        if ( GetEventHandler()->ProcessEvent(event) )
+        if ( HandleWindowEvent(event) )
             processed = true;
         //else: continue with generating wxEVT_CONTEXT_MENU in base class code
     }
@@ -2280,7 +2309,7 @@ WXLRESULT wxTreeCtrl::MSWWindowProc(WXUINT nMsg, WXWPARAM wParam, WXLPARAM lPara
                     wxTreeEvent event(wxEVT_COMMAND_TREE_END_DRAG, this, htItem);
                     event.m_pointDrag = wxPoint(x, y);
 
-                    (void)GetEventHandler()->ProcessEvent(event);
+                    (void)HandleWindowEvent(event);
 
                     // if we don't do it, the tree seems to think that 2 items
                     // are selected simultaneously which is quite weird
@@ -2632,7 +2661,7 @@ bool wxTreeCtrl::MSWOnNotify(int idCtrl, WXLPARAM lParam, WXLPARAM *result)
 
                    wxTreeEvent event2(wxEVT_COMMAND_TREE_ITEM_ACTIVATED,
                                         this, item);
-                   (void)GetEventHandler()->ProcessEvent(event2);
+                   (void)HandleWindowEvent(event2);
                 }
             }
             break;
@@ -2646,6 +2675,7 @@ bool wxTreeCtrl::MSWOnNotify(int idCtrl, WXLPARAM lParam, WXLPARAM *result)
         // that can be used to regulate this incorrect behavior.  The
         // following messages will allow only the unlocked item's selection
         // state to change
+
         case TVN_ITEMCHANGINGA:
         case TVN_ITEMCHANGINGW:
             {
@@ -2654,7 +2684,7 @@ bool wxTreeCtrl::MSWOnNotify(int idCtrl, WXLPARAM lParam, WXLPARAM *result)
                 {
                     // get info about the item about to be changed
                     NMTVITEMCHANGE* info = (NMTVITEMCHANGE*)lParam;
-                    if (info->hItem != gs_unlockItem)
+                    if (TreeItemUnlocker::IsLocked(info->hItem))
                     {
                         // item's state is locked, don't allow the change
                         // returning 1 will disallow the change
@@ -2849,7 +2879,7 @@ bool wxTreeCtrl::MSWOnNotify(int idCtrl, WXLPARAM lParam, WXLPARAM *result)
     if ( event.m_item.IsOk() )
         event.SetClientObject(GetItemData(event.m_item));
 
-    bool processed = GetEventHandler()->ProcessEvent(event);
+    bool processed = HandleWindowEvent(event);
 
     // post processing
     switch ( hdr->code )