From b795a254dd97f738d99775c58dfce37f90157fb4 Mon Sep 17 00:00:00 2001
From: sekelsenmat <sekelsenmat@lazarus-ide.org>
Date: Thu, 4 Aug 2016 06:57:58 +0000
Subject: [PATCH] customdrawn: Fixes bug #21573 problems in TCDScrollBar slider
 mouse drag

git-svn-id: trunk@52782 -
---
 lcl/customdrawncontrols.pas | 27 ++++++++++++++++++---------
 lcl/interfaces/lcl.lpk      |  5 +++++
 lcl/lclbase.lpk             |  5 +++++
 3 files changed, 28 insertions(+), 9 deletions(-)

diff --git a/lcl/customdrawncontrols.pas b/lcl/customdrawncontrols.pas
index 2202b6f333..edb9a7fbf3 100644
--- a/lcl/customdrawncontrols.pas
+++ b/lcl/customdrawncontrols.pas
@@ -396,6 +396,7 @@ type
   private
     FKind: TScrollBarKind;
     procedure SetKind(AValue: TScrollBarKind);
+    procedure GetBorderSizes(out ALeft, ARight: Integer);
   protected
     function GetPositionFromMousePos(X, Y: Integer): integer; override;
     function GetButtonFromMousePos(X, Y: Integer): TCDControlState; override;
@@ -2372,7 +2373,7 @@ end;
 function TCDPositionedControl.GetPositionDisplacementWithMargins(AOldMousePos,
   ANewMousePos: TPoint; ALeftMargin, ARightMargin: Integer; AIsHorizontal: Boolean): Integer;
 var
-  lCoord, lSize: Integer;
+  lCoord, lSize, lCurPos: Integer;
 begin
   if AIsHorizontal then
   begin
@@ -2385,12 +2386,12 @@ begin
     lSize := Height;
   end;
 
-  Result := FMin + (lCoord - ALeftMargin) * (FMax - FMin + 1) div (lSize - ARightMargin - ALeftMargin);
-  Result := FPositionAtMouseDown + Result;
+  Result := FMin + lCoord * (FMax - FMin + 1) div (lSize - ARightMargin - ALeftMargin);
+  lCurPos := Result + FPositionAtMouseDown;
 
   // sanity check
-  if Result > FMax then Result := FMax;
-  if Result < FMin then Result := FMin;
+  if lCurPos > FMax then Result := FMax - FPositionAtMouseDown;
+  if lCurPos < FMin then Result := FMin - FPositionAtMouseDown;
 end;
 
 function TCDPositionedControl.GetButtonFromMousePos(X, Y: Integer): TCDControlState;
@@ -2551,12 +2552,21 @@ begin
   if not (csLoading in ComponentState) then Invalidate;
 end;
 
+procedure TCDScrollBar.GetBorderSizes(out ALeft, ARight: Integer);
+begin
+  ALeft := FDrawer.GetMeasures(TCDSCROLLBAR_LEFT_SPACING) +
+    FDrawer.GetMeasures(TCDSCROLLBAR_LEFT_BUTTON_POS) +
+    FDrawer.GetMeasures(TCDSCROLLBAR_BUTTON_WIDTH);
+  ARight := FDrawer.GetMeasures(TCDSCROLLBAR_RIGHT_SPACING) +
+    FDrawer.GetMeasures(TCDSCROLLBAR_RIGHT_BUTTON_POS) +
+    FDrawer.GetMeasures(TCDSCROLLBAR_BUTTON_WIDTH);
+end;
+
 function TCDScrollBar.GetPositionFromMousePos(X, Y: Integer): integer;
 var
   lLeftBorder, lRightBorder: Integer;
 begin
-  lLeftBorder := FDrawer.GetMeasures(TCDSCROLLBAR_LEFT_SPACING);
-  lRightBorder := FDrawer.GetMeasures(TCDSCROLLBAR_RIGHT_SPACING);
+  GetBorderSizes(lLeftBorder, lRightBorder);
 
   Result := GetPositionFromMousePosWithMargins(X, Y, lLeftBorder, lRightBorder, FKind = sbHorizontal, False);
 end;
@@ -2592,8 +2602,7 @@ function TCDScrollBar.GetPositionDisplacement(AOldMousePos, ANewMousePos: TPoint
 var
   lLeftBorder, lRightBorder: Integer;
 begin
-  lLeftBorder := FDrawer.GetMeasures(TCDSCROLLBAR_LEFT_SPACING);
-  lRightBorder := FDrawer.GetMeasures(TCDSCROLLBAR_RIGHT_SPACING);
+  GetBorderSizes(lLeftBorder, lRightBorder);
 
   Result := GetPositionDisplacementWithMargins(AOldMousePos, ANewMousePos,
     lLeftBorder, lRightBorder, FKind = sbHorizontal);
diff --git a/lcl/interfaces/lcl.lpk b/lcl/interfaces/lcl.lpk
index c40bb5aca9..2798120afe 100644
--- a/lcl/interfaces/lcl.lpk
+++ b/lcl/interfaces/lcl.lpk
@@ -113,6 +113,11 @@ end;"/>
           <ValueDescriptions Count="2"/>
         </Item2>
       </BuildMacros>
+      <Linking>
+        <Debugging>
+          <DebugInfoType Value="dsDwarf2"/>
+        </Debugging>
+      </Linking>
       <Other>
         <CompilerMessages>
           <IgnoredMessages idx5044="True"/>
diff --git a/lcl/lclbase.lpk b/lcl/lclbase.lpk
index 3d0993f479..a3d6de8cfd 100644
--- a/lcl/lclbase.lpk
+++ b/lcl/lclbase.lpk
@@ -13,6 +13,11 @@
       </SearchPaths>
       <Conditionals Value="if SrcOS&lt;>'win' then
   UnitPath := 'nonwin32';"/>
+      <Linking>
+        <Debugging>
+          <DebugInfoType Value="dsDwarf2"/>
+        </Debugging>
+      </Linking>
       <Other>
         <Verbosity>
           <ShowNotes Value="False"/>