moved code from TControlScrollBar to TScrollingWinControl, deriving TScrollingWinControl from TCustomControl from Flavio

git-svn-id: trunk@9952 -

lcl/forms.pp

@@ -104,7 +104,6 @@ type
     function VisibleIsStored: boolean; virtual;
     procedure AutoCalcRange; virtual;
     procedure ControlUpdateScrollBars; virtual;
-    procedure ScrollControlBy(DeltaX, DeltaY: integer); virtual;
     procedure ScrollHandler(var Message: TLMScroll);
     procedure SetIncrement(const AValue: TScrollBarInc); virtual;
     procedure SetPage(const AValue: TScrollBarInc); virtual;
@@ -113,7 +112,7 @@ type
     procedure SetSize(const AValue: integer); virtual;
     procedure SetSmooth(const Value: Boolean); virtual;
     procedure SetVisible(const Value: Boolean); virtual;
-    Procedure UpdateScrollBar; virtual;
+    procedure UpdateScrollBar; virtual;
   public
     constructor Create(AControl: TWinControl; AKind: TScrollBarKind);
     procedure Assign(Source: TPersistent); override;
@@ -136,38 +135,32 @@ type
 
   { TScrollingWinControl }
 
-  TScrollingWinControl = class(TWinControl)
+  TScrollingWinControl = class(TCustomControl)
   private
     FHorzScrollBar: TControlScrollBar;
     FVertScrollBar: TControlScrollBar;
     FAutoScroll: Boolean;
-    FOnPaint: TNotifyEvent;
-    FCanvas: TControlCanvas;
     FIsUpdating: Boolean;
     procedure SetAutoScroll(Value: Boolean);
     procedure SetHorzScrollBar(Value: TControlScrollBar);
     procedure SetVertScrollBar(Value: TControlScrollBar);
+    //todo: rename to IsScrollbarsStored
     Function StoreScrollBars : Boolean;
   protected
     procedure AlignControls(AControl: TControl; var ARect: TRect); override;
     procedure CreateWnd; override;
     function  GetClientScrollOffset: TPoint; override;
-    Procedure WMEraseBkgnd(var Message: TLMEraseBkgnd); message LM_ERASEBKGND;
-    procedure WMPaint(var message: TLMPaint); message LM_PAINT;
     procedure DoOnResize; override;
     procedure WMHScroll(var Message : TLMHScroll); message LM_HScroll;
     procedure WMVScroll(var Message : TLMVScroll); message LM_VScroll;
     procedure ScrollBy(DeltaX, DeltaY: Integer);
-    property OnPaint: TNotifyEvent read FOnPaint write FOnPaint;
+    procedure ComputeScrollbars; virtual;
+    procedure ScrollbarHandler(p_ScrollKind: TScrollBarKind; p_OldPosition: Integer); virtual;
   public
     Constructor Create(AOwner : TComponent); Override;
     Destructor Destroy; Override;
-    procedure Paint; dynamic;
+    procedure UpdateScrollbars;
-    procedure PaintWindow(dc : Hdc); override;
-    procedure UpdateScrollbars; virtual;
     function HasVisibleScrollbars: boolean; virtual;
-    procedure DestroyWnd; override;
-    property Canvas: TControlCanvas read FCanvas;
   published
     property AutoScroll: Boolean read FAutoScroll write SetAutoScroll;
     property HorzScrollBar: TControlScrollBar

lcl/include/controlscrollbar.inc

@@ -47,10 +47,8 @@ begin
   // scroll content of FControl
   OldPosition:=FPosition;
   FPosition := Value;
-  if Kind = sbVertical then
+  if FControl is TScrollingWinControl then
-    ScrollControlBy(0, OldPosition - FPosition)
+    TScrollingWinControl(FControl).ScrollbarHandler(Kind, OldPosition);
-  else
-    ScrollControlBy(OldPosition - FPosition, 0);
 
   // check that the new position is also set on the scrollbar
   if HandleAllocated
@@ -169,12 +167,6 @@ begin
   ControlUpdateScrollBars;
 end;
 
-procedure TControlScrollBar.ScrollControlBy(DeltaX, DeltaY: integer);
-begin
-  if FControl is TScrollingWinControl then
-    TScrollingWinControl(FControl).ScrollBy(DeltaX, DeltaY);
-end;
-
 procedure TControlScrollBar.SetSmooth(const Value: Boolean);
 begin
   // only used by the ScrollHandler procedure
@@ -237,58 +229,19 @@ end;
 procedure TControlScrollBar.UpdateScrollBar;
 var
   ScrollInfo: TScrollInfo;
-  SBSize : Longint;
-  OtherScrollbar: TControlScrollBar;
-  CurMax: Integer;
 begin
+  //todo: probably needs to be moved somewhere else.
   FAutoRange := 0;
 
   if FControl is TScrollingWinControl then begin
     ScrollInfo.cbSize := SizeOf(ScrollInfo);
     ScrollInfo.fMask := SIF_ALL;
     ScrollInfo.nMin := 0;
+    ScrollInfo.nMax := FRange;
     ScrollInfo.nPos := FPosition;
     ScrollInfo.nTrackPos := FPosition;
-
+    if HandleAllocated then
-    With TScrollingWinControl(FControl) do begin
+      SetScrollInfo(FControl.Handle, IntfBarKind[Kind], ScrollInfo, FVisible);
-      // page
-      if Self.Kind=sbVertical then
-        FPage := TScrollBarInc(Min(ClientHeight - 1,High(FPage)))
-      else
-        FPage := TScrollBarInc(Min(ClientWidth - 1,High(FPage)));
-      ScrollInfo.nPage := FPage;
-
-      // range
-      OtherScrollbar:=GetOtherScrollBar;
-      If OtherScrollbar.FVisible then
-        SBSize := OtherScrollbar.Size
-      else
-        SBSize := 0;
-      if Kind=sbVertical then begin
-        SBSize:=ClientHeight - SBSize;
-      end else begin
-        SBSize:=ClientWidth - SBSize;
-      end;
-      if (fRange>SBSize) and (SBSize>0) then   FAutoRange := (FRange - SBSize)
-                                        else   FAutoRange := 0;
-      ScrollInfo.nMax := FRange;
-
-      // visible
-      if Kind=sbVertical then
-        CurMax:=Height
-      else
-        CurMax:=Width;
-      If (Self.FVisible and not FAutoScroll)
-      or (FAutoScroll and (ScrollInfo.nMax > 0) and (ScrollInfo.nMax > CurMax))
-      then
-        Self.FVisible := True
-      else
-        Self.FVisible := False;
-
-      // transmit scollinfo to interface
-      if HandleAllocated then
-        SetScrollInfo(Handle, IntfBarKind[Kind], ScrollInfo, Self.FVisible);
-    end
   end;
 
   SetPosition(ScrollInfo.nTrackPos);

lcl/include/customform.inc

@@ -760,12 +760,12 @@ Procedure TCustomForm.PaintWindow(DC : Hdc);
 begin
   // FCanvas.Lock;
   try
-    FCanvas.Handle := DC;
+    Canvas.Handle := DC;
     //DebugLn('[TCustomForm.PaintWindow] ',ClassName,' DC=',DbgS(DC,8),'  ',DbgS(FCanvas.Handle,8));
     try
       if FDesigner <> nil then FDesigner.PaintGrid else Paint;
     finally
-      FCanvas.Handle := 0;
+      Canvas.Handle := 0;
     end;
   finally
     // FCanvas.Unlock;

lcl/include/scrollingwincontrol.inc

@@ -56,42 +56,6 @@ begin
   inherited AlignControls(AControl, ARect);
 end;
 
-Procedure TScrollingWinControl.WMEraseBkgnd(var Message: TLMEraseBkgnd);
-begin
-  inherited WMEraseBkgnd(Message);
-end;
-
-procedure TScrollingWinControl.WMPaint(var Message: TLMPaint);
-begin
-  Include(FControlState, csCustomPaint);
-  try
-    inherited WMPaint(Message);
-  finally
-    Exclude(FControlState, csCustomPaint);
-  end;
-end;
-
-Procedure TScrollingWinControl.Paint;
-begin
-  if Assigned (FOnPaint) then
-    FOnPaint(Self);
-end;
-
-Procedure TScrollingWinControl.PaintWindow(DC : Hdc);
-begin
-  FCanvas.Lock;
-  try
-    FCanvas.Handle := DC;
-    try
-      Paint;
-    finally
-      FCanvas.Handle := 0;
-    end;
-  finally
-    FCanvas.Unlock;
-  end;
-end;
-
 procedure TScrollingWinControl.DoOnResize;
 begin
   inherited DoOnResize;
@@ -110,11 +74,64 @@ begin
   FVertScrollbar.Assign(Value);
 end;
 
+procedure TScrollingWinControl.ComputeScrollbars;
+
+  procedure UpdateRange(p_Bar: TControlScrollBar);
+  var
+    SBSize: Longint;
+    OtherScrollbar: TControlScrollBar;
+  begin
+    p_Bar.FAutoRange := 0;
+    OtherScrollbar := p_Bar.GetOtherScrollBar;
+    If OtherScrollbar.FVisible then
+      SBSize := OtherScrollbar.Size
+    else
+      SBSize := 0;
+    if p_Bar.Kind = sbVertical then
+      SBSize := ClientHeight - SBSize
+    else
+      SBSize := ClientWidth - SBSize;
+    if (p_Bar.fRange>SBSize) and (SBSize>0) then
+      p_Bar.FAutoRange := (p_Bar.FRange - SBSize)
+    else
+      p_Bar.FAutoRange := 0;
+  end;
+  
+  procedure UpdateVisible(p_Bar: TControlScrollBar);
+  var
+    CurMax: Integer;
+  begin
+    if p_Bar.Kind = sbVertical then
+      CurMax := Height
+    else
+      CurMax := Width;
+    If (p_Bar.FVisible and not FAutoScroll)
+      or (FAutoScroll and (p_Bar.FRange > 0) and (p_Bar.FRange > CurMax))
+    then
+      p_Bar.FVisible := True
+    else
+      p_Bar.FVisible := False;
+  end;
+  
+begin
+  //todo: why doesn't it simply use ClientWidth/Height?
+  // page
+  HorzScrollbar.FPage := Min(ClientWidth -1, High(HorzScrollbar.FPage));
+  VertScrollbar.FPage := Min(ClientHeight -1, High(VertScrollbar.FPage));
+  // range
+  UpdateRange(VertScrollbar);
+  UpdateRange(VertScrollbar);
+  // visible
+  UpdateVisible(HorzScrollbar);
+  UpdateVisible(VertScrollbar);
+end;
+
 Procedure TScrollingWinControl.UpdateScrollbars;
 begin
   If FIsUpdating then exit;
   FIsUpdating := True;
   try
+    ComputeScrollbars;
     FVertScrollbar.UpdateScrollbar;
     FHorzScrollbar.UpdateScrollbar;
   finally
@@ -128,13 +145,6 @@ begin
       and (HorzScrollBar<>nil) and HorzScrollBar.Visible;
 end;
 
-procedure TScrollingWinControl.DestroyWnd;
-begin
-  inherited DestroyWnd;
-  if Canvas<>nil then
-    Canvas.FreeHandle;
-end;
-
 Function TScrollingWinControl.StoreScrollBars : Boolean;
 begin
   Result := Not AutoScroll;
@@ -144,10 +154,19 @@ procedure TScrollingWinControl.ScrollBy(DeltaX, DeltaY: Integer);
 begin
   if HandleAllocated then begin
     TWSScrollingWinControlClass(WidgetSetClass).ScrollBy(Self, DeltaX, DeltaY);
+    //todo: shouldn't call Invalidate. Instead, the TWidgetSet should call it if it needs to.
     Invalidate;
   end;
 end;
 
+procedure TScrollingWinControl.ScrollbarHandler(p_ScrollKind: TScrollBarKind; p_OldPosition: Integer);
+begin
+  if p_ScrollKind = sbVertical then
+    ScrollBy(0, FVertScrollBar.Position - p_OldPosition)
+  else
+    ScrollBy(FHorzScrollBar.Position - p_OldPosition, 0);
+end;
+
 Procedure TScrollingWinControl.WMVScroll(var Message : TLMVScroll);
 begin
   VertScrollbar.ScrollHandler(Message);
@@ -162,9 +181,6 @@ Constructor TScrollingWinControl.Create(AOwner : TComponent);
 begin
   Inherited Create(AOwner);
 
-  FCanvas := TControlCanvas.Create;
-  FCanvas.Control := Self;
-
   FVertScrollbar := TControlScrollBar.Create(Self, sbVertical);
   FHorzScrollbar := TControlScrollBar.Create(Self, sbHorizontal);
 
@@ -177,7 +193,6 @@ Destructor TScrollingWinControl.Destroy;
 begin
   FreeThenNil(FHorzScrollBar);
   FreeThenNil(FVertScrollBar);
-  FreeThenNil(FCanvas);
   inherited Destroy;
 end;