Remove all hibernation bug fix hacks per v4.24.2

This is a merge of two commits proposed by @SirRufo per PR#160, with
trivial FrOverview.dfm changes removed.

Author: delphidabbler

Src/FmMain.pas

@@ -526,12 +526,6 @@   TMainForm = class(THelpAwareForm)
       ///  <summary>Object that manages favourites.</summary>
       fFavouritesMgr: TFavouritesManager;
 
-    ///  <summary>Handles the <c>WM_POWERBROADCAST</c> messages to detect and
-    ///  respond to hibernation messages.</summary>
-    ///  <remarks>!! HACK necessary as part of the fix for an obscure bug. See
-    ///  https://github.com/delphidabbler/codesnip/issues/70</remarks>
-    procedure WMPowerBroadcast(var Msg: TMessage); message WM_POWERBROADCAST;
-
     ///  <summary>Displays view item given by TViewItemAction instance
     ///  referenced by Sender and adds to history list.</summary>
     procedure ActViewItemExecute(Sender: TObject);
@@ -1601,19 +1595,5 @@ procedure TMainForm.splitVertCanResize(Sender: TObject;
     Accept := False;
 end;
 
-procedure TMainForm.WMPowerBroadcast(var Msg: TMessage);
-begin
-  // !! HACK
-  // Sometimes when the computer is resumed from hibernation the tree view in
-  // the overview frame is destroyed and recreated by Windows. Unfortunately the
-  // IView instances associated with the recreated tree nodes are lost.
-  // Attempting to read those (now nil) IView instances was resulting in an
-  // access violation.
-  case Msg.WParam of
-    PBT_APMSUSPEND:
-      fMainDisplayMgr._HACK_PrepareForHibernate;
-  end;
-end;
-
 end.
 

Src/FrOverview.pas

@@ -26,29 +26,6 @@ interface
 
 type
 
-  // !! HACK
-  // Horrible hack to expose CreateWnd for overiding TTreeView.CreateWnd for the
-  // existing TTreeView component of TOverviewFrame. The hack avoids having to
-  // remove the component and replacing it with a descendant class that is
-  // manually constructed at run time.
-  // This is here to enable the tree view to be recreated with correctly
-  // instantiated TViewItemTreeNode nodes after Windows recreates the tree
-  // behind the scenes after resuming from hibernation.
-  // I am deeply ashamed of this hack.
-  TTreeView = class(ComCtrls.TTreeView)
-  strict private
-    var
-      _HACK_fOnAfterCreateNilViews: TNotifyEvent;
-  protected
-    procedure CreateWnd; override;
-  public
-    ///  <summary>!! HACK. Event triggered after the inherited CreateWnd is
-    ///  called. Only called if the tree view has nil references to IView
-    ///  objects.</summary>
-    property _HACK_OnAfterCreateNilViews: TNotifyEvent
-      read _HACK_fOnAfterCreateNilViews write _HACK_fOnAfterCreateNilViews;
-  end;
-
   {
   TOverviewFrame:
     Titled frame that displays lists of snippets grouped in various ways and
@@ -237,10 +214,6 @@       TTVDraw = class(TSnippetsTVDraw)
     procedure RestoreTreeState;
       {Restores last saved treeview expansion state from memory.
       }
-    ///  <summary>!! HACK: Sets an event handler on the tree view to work
-    ///  around a bug that can occur after resuming from hibernation.</summary>
-    ///  <remarks>Method of IOverviewDisplayMgr.</remarks>
-    procedure _HACK_SetHibernateHandler(const AHandler: TNotifyEvent);
     { IPaneInfo }
     function IsInteractive: Boolean;
       {Checks if the pane is currently interactive with user.
@@ -982,12 +955,6 @@ procedure TOverviewFrame.UpdateTreeState(const State: TTreeNodeAction);
   end;
 end;
 
-procedure TOverviewFrame._HACK_SetHibernateHandler(
-  const AHandler: TNotifyEvent);
-begin
-  tvSnippets._HACK_OnAfterCreateNilViews := AHandler;
-end;
-
 { TOverviewFrame.TTVDraw }
 
 function TOverviewFrame.TTVDraw.IsSectionHeadNode(
@@ -1026,24 +993,5 @@ function TOverviewFrame.TTVDraw.IsUserDefinedNode(
     Result := False;
 end;
 
-{ TTreeView }
-
-procedure TTreeView.CreateWnd;
-var
-  HasNilViews: Boolean;
-  Node: TTreeNode;
-begin
-  inherited;
-  HasNilViews := False;
-  for Node in Items do
-  begin
-    HasNilViews := not Assigned((Node as TViewItemTreeNode).ViewItem);
-    if HasNilViews then
-      Break;
-  end;
-  if HasNilViews and Assigned(_HACK_fOnAfterCreateNilViews) then
-    _HACK_fOnAfterCreateNilViews(Self);
-end;
-
 end.
 

Src/IntfFrameMgrs.pas

@@ -19,7 +19,6 @@ interface
 uses
   // Delphi
   SHDocVw, ActiveX,
-  Classes, // !! For HACK
   // Project
   Browser.IntfDocHostUI, DB.USnippet, Compilers.UGlobals, UCommandBars, UView;
 
@@ -146,9 +145,6 @@ interface
     ///  <summary>Restore expand / collapse state of treeview to last save
     ///  state.</summary>
     procedure RestoreTreeState;
-    ///  <summary>!! HACK: Sets an event handler on the tree view to work
-    ///  around a bug that can occur after resuming from hibernation.</summary>
-    procedure _HACK_SetHibernateHandler(const AHandler: TNotifyEvent);
   end;
 
 type

Src/UMainDisplayMgr.pas

@@ -165,11 +165,6 @@   TMainDisplayMgr = class(TObject)
     procedure DisplayViewItem(ViewItem: IView; Mode: TDetailPageDisplayMode);
       overload;
 
-    ///  <summary>!! HACK event handle to redisplay the overview pane treeview.
-    ///  Called only if Windows has mysteriously recreated the treeview and lost
-    ///  necessary object references.</summary>
-    procedure _HACK_HibernateHandler(Sender: TObject);
-
   public
     ///  <summary>Object contructor. Sets up object to work with given frame
     ///  manager objects.</summary>
@@ -297,13 +292,6 @@   TMainDisplayMgr = class(TObject)
     /// <summary>Prepares display ready for database to be reloaded.</summary>
     procedure PrepareForDBReload;
 
-    ///  <summary>!!HACK: gets the overview frame prepared for program
-    ///  hibernation.</summary>
-    ///  <remarks>Saves the overview tree view state ready for restoring after
-    ///  hibernation if Windows has recreated the overview pane's treeview,
-    ///  losing necessary IView object references..</remarks>
-    procedure _HACK_PrepareForHibernate;
-
   end;
 
 
@@ -704,21 +692,5 @@ procedure TMainDisplayMgr.UpdateOverviewTreeState(const State: TTreeNodeAction);
   (fOverviewMgr as IOverviewDisplayMgr).UpdateTreeState(State);
 end;
 
-procedure TMainDisplayMgr._HACK_HibernateHandler(Sender: TObject);
-begin
-  (fOverviewMgr as IOverviewDisplayMgr).Display(Query.Selection, True);
-  (fOverviewMgr as IOverviewDisplayMgr).RestoreTreeState;
-  // disable this handler until next resume from hibernation
-  (fOverviewMgr as IOverviewDisplayMgr)._HACK_SetHibernateHandler(nil);
-end;
-
-procedure TMainDisplayMgr._HACK_PrepareForHibernate;
-begin
-  (fOverviewMgr as IOverviewDisplayMgr).SaveTreeState;
-  (fOverviewMgr as IOverviewDisplayMgr)._HACK_SetHibernateHandler(
-    _HACK_HibernateHandler
-  );
-end;
-
 end.