* (4.8 branch) Synchronize with main svn up to version 206

git-svn-id: https://svn.code.sf.net/p/lazarus-ccr/svn@1134 8e941d3f-bd1b-0410-a28a-d453659cc2b4

components/virtualtreeview-new/branches/4.8/VirtualTrees.pas

@@ -27,6 +27,10 @@ unit VirtualTrees;
 // (C) 1999-2001 digital publishing AG. All Rights Reserved.
 //----------------------------------------------------------------------------------------------------------------------
 //
+//  July 2009
+//   - Bug fix: TWorkerThread will no longer reference the tree after it has been destroyed (Mantis issue #384)
+//   - Bug fix: TBaseVirtualTree.InternalConnectNode checked the expanded state of the wrong node if Mode was
+//              amAddChildFirst or amAddChildLast
 //  June 2009
 //   - Bug fix: fixed some issues concerning the vista theme handling
 //   - Improvement: removed hidden node handling in this branch
@@ -4008,6 +4012,7 @@ type
     FWaiterList: TThreadList;
     FRefCount: Cardinal;
   protected
+    procedure CancelValidation(Tree: TBaseVirtualTree);
     procedure ChangeTreeStates(EnterStates, LeaveStates: TChangeStates);
     procedure Execute; override;
   public
@@ -4987,6 +4992,10 @@ begin
     // Make sure there is no reference remaining to the releasing tree.
     Tree.InterruptValidation;
 
+    // Borland change (used to debug shutdown issue with dangling FCurrentTree reference)
+    Assert(WorkerThread.FCurrentTree <> Tree, 'WorkerThread.FCurrentTree dangling reference!');
+
+
     if WorkerThread.FRefCount = 0 then
     begin
       with WorkerThread do
@@ -5036,6 +5045,26 @@ end;
 
 //----------------------------------------------------------------------------------------------------------------------
 
+procedure TWorkerThread.CancelValidation(Tree: TBaseVirtualTree);
+
+var
+  Msg: TMsg;
+
+begin
+  // Wait for any references to this tree to be released.
+  // Pump WM_CHANGESTATE messages so the thread doesn't block on SendMessage calls.
+  while FCurrentTree = Tree do
+  begin
+    if Tree.HandleAllocated and PeekMessage(Msg, Tree.Handle, WM_CHANGESTATE, WM_CHANGESTATE, PM_REMOVE) then
+    begin
+      TranslateMessage(Msg);
+      DispatchMessage(Msg);
+    end;
+  end;
+end;
+
+//----------------------------------------------------------------------------------------------------------------------
+
 procedure TWorkerThread.ChangeTreeStates(EnterStates, LeaveStates: TChangeStates);
 
 begin
@@ -5078,14 +5107,14 @@ begin
       end;
 
       // Something to do?
-      try
       if Assigned(FCurrentTree) then
       begin
+        try
           ChangeTreeStates([csValidating], [csUseCache]);
           EnterStates := [];
           if not (tsStopValidation in FCurrentTree.FStates) and FCurrentTree.DoValidateCache then
             EnterStates := [csUseCache];
-        end;
+
         finally
           LeaveStates := [csValidating, csStopValidation];
           if csUseCache in EnterStates then
@@ -5096,6 +5125,7 @@ begin
       end;
     end;
   end;
+end;
 
 //----------------------------------------------------------------------------------------------------------------------
 
@@ -5113,6 +5143,7 @@ begin
   finally
     FWaiterList.UnlockList;
   end;
+  CancelValidation(Tree);
 end;
 
 //----------------------------------------------------------------------------------------------------------------------
@@ -12900,10 +12931,8 @@ end;
 
 procedure TBaseVirtualTree.InterruptValidation;
 
-// Waits until the worker thread has stopped validating the caches of this tree.
+var
-
+  WasValidating: Boolean;
-//var
-//  Msg: TMsg;
 
 begin
   DoStateChange([tsStopValidation], [tsUseCache]);
@@ -12911,35 +12940,13 @@ begin
   // Check the worker thread existance. It might already be gone (usually on destruction of the last tree).
   if Assigned(WorkerThread) then
   begin
-    if tsValidating in FStates then
+    WasValidating := (tsValidating in FStates);
-    begin
-      // Do a hard break until the worker thread has stopped validation.
-      while (tsValidating in FStates) and (WorkerThread.CurrentTree = Self) and not Application.Terminated do
-      begin
-        // Pump our own messages to avoid a deadlock.
-        //todo_lcl_check
-        Application.ProcessMessages;
-        {
-        if PeekMessage(Msg, Handle, 0, 0, PM_REMOVE) then
-        begin
-          if Msg.message = WM_QUIT then
-          begin
-            PostQuitMessage(Msg.WParam);
-            Break;
-          end;
-          TranslateMessage(Msg);
-          DispatchMessage(Msg);
-        end;
-        }
-      end;
-      DoStateChange([tsValidationNeeded]);
-    end
-    else // Remove any pending validation.
     WorkerThread.RemoveTree(Self);
+    if WasValidating then
+      DoStateChange([tsValidationNeeded]);
   end;
   {$endif}
 end;
-
 //----------------------------------------------------------------------------------------------------------------------
 
 function TBaseVirtualTree.IsFirstVisibleChild(Parent, Node: PVirtualNode): Boolean;
@@ -21505,7 +21512,7 @@ begin
           Include(Destination.States, vsHasChildren);
           AdjustTotalCount(Destination, Node.TotalCount, True);
           // Add the new node's height only if its parent is expanded.
-          if Destination.Parent.States * [vsExpanded, vsVisible] = [vsExpanded, vsVisible] then
+          if Destination.States * [vsExpanded, vsVisible] = [vsExpanded, vsVisible] then
             AdjustTotalHeight(Destination, Node.TotalHeight, True);
           if FullyVisible[Node] then
             Inc(FVisibleCount, CountVisibleChildren(Node) + 1);
@@ -21536,7 +21543,7 @@ begin
           Include(Destination.States, vsHasChildren);
           AdjustTotalCount(Destination, Node.TotalCount, True);
           // Add the new node's height only if its parent is expanded.
-          if Destination.Parent.States * [vsExpanded, vsVisible] = [vsExpanded, vsVisible] then
+          if Destination.States * [vsExpanded, vsVisible] = [vsExpanded, vsVisible] then
             AdjustTotalHeight(Destination, Node.TotalHeight, True);
           if FullyVisible[Node] then
             Inc(FVisibleCount, CountVisibleChildren(Node) + 1);