From e6b1840fc4bafcf4be7dc19e2b3a6e05494595eb Mon Sep 17 00:00:00 2001
From: ask <ask@lazarus-ide.org>
Date: Sun, 26 Jun 2011 08:45:35 +0000
Subject: [PATCH] TAChart: Add TChartSeriesLegend.Order property

git-svn-id: trunk@31395 -
---
 components/tachart/demo/legend/main.lfm |  3 ++-
 components/tachart/tacustomseries.pas   |  7 ++++++-
 components/tachart/tagraph.pas          |  7 +++++++
 components/tachart/talegend.pas         | 27 ++++++++++++++++++++++++-
 4 files changed, 41 insertions(+), 3 deletions(-)

diff --git a/components/tachart/demo/legend/main.lfm b/components/tachart/demo/legend/main.lfm
index 1d35ff0111..a64ffbfe3b 100644
--- a/components/tachart/demo/legend/main.lfm
+++ b/components/tachart/demo/legend/main.lfm
@@ -60,8 +60,9 @@ object Form1: TForm1
       Source = ListChartSource2
     end
     object Chart1FuncSeries1: TFuncSeries
-      Legend.OnDraw = Chart1FuncSeries1DrawLegend
+      Legend.Order = 0
       Legend.UserItemsCount = 2
+      Legend.OnDraw = Chart1FuncSeries1DrawLegend
       Extent.XMax = 5
       Extent.UseXMin = True
       Extent.UseXMax = True
diff --git a/components/tachart/tacustomseries.pas b/components/tachart/tacustomseries.pas
index f870a9ed7c..e7acae6e92 100644
--- a/components/tachart/tacustomseries.pas
+++ b/components/tachart/tacustomseries.pas
@@ -311,13 +311,18 @@ end;
 
 procedure TCustomChartSeries.GetLegendItemsBasic(AItems: TChartLegendItems);
 var
-  i: Integer;
+  i, oldCount: Integer;
 begin
+  oldCount := AItems.Count;
   if Assigned(Legend.OnDraw) then
     for i := 0 to Legend.UserItemsCount - 1 do
       AItems.Add(TLegendItemUserDrawn.Create(i, Legend.OnDraw, Title))
   else
     GetLegendItems(AItems);
+  for i := oldCount to AItems.Count - 1 do
+    with AItems[i] do
+      if Order = LEGEND_ITEM_ORDER_AS_ADDED then
+        Order := Legend.Order;
 end;
 
 function TCustomChartSeries.GetNearestPoint(
diff --git a/components/tachart/tagraph.pas b/components/tachart/tagraph.pas
index a83007f80e..b5551940e7 100644
--- a/components/tachart/tagraph.pas
+++ b/components/tachart/tagraph.pas
@@ -927,6 +927,7 @@ end;
 function TChart.GetLegendItems(AIncludeHidden: Boolean): TChartLegendItems;
 var
   i: Integer;
+  j: Integer = MaxInt;
 begin
   Result := TChartLegendItems.Create;
   try
@@ -934,6 +935,12 @@ begin
       with Series[i] do
         if AIncludeHidden or (Active and GetShowInLegend) then
           GetLegendItemsBasic(Result);
+    for i := Result.Count - 1 downto 0 do
+      if Result[i].Order = LEGEND_ITEM_ORDER_AS_ADDED then begin
+        Result[i].Order := j;
+        j -= 1;
+      end;
+    Result.Sort(@LegendItemCompare);
   except
     FreeAndNil(Result);
     raise;
diff --git a/components/tachart/talegend.pas b/components/tachart/talegend.pas
index 42c3e47268..9f0320f7a7 100644
--- a/components/tachart/talegend.pas
+++ b/components/tachart/talegend.pas
@@ -27,6 +27,7 @@ const
   DEF_LEGEND_SPACING = 4;
   DEF_LEGEND_MARGIN = 4;
   DEF_LEGEND_SYMBOL_WIDTH = 20;
+  LEGEND_ITEM_ORDER_AS_ADDED = -1;
 
 type
   { TLegendItem }
@@ -34,12 +35,14 @@ type
   TLegendItem = class
   private
     FColor: TColor;
+    FOrder: Integer;
     FText: String;
   public
     constructor Create(const AText: String; AColor: TColor = clTAColor);
     procedure Draw(ADrawer: IChartDrawer; const ARect: TRect); virtual;
   public
     property Color: TColor read FColor write FColor;
+    property Order: Integer read FOrder write FOrder;
   end;
 
   TLegendItemDrawEvent = procedure (
@@ -181,9 +184,11 @@ type
   private
     FMultiplicity: TLegendMultiplicity;
     FOnDraw: TLegendItemDrawEvent;
+    FOrder: Integer;
     FUserItemsCount: Integer;
     procedure SetMultiplicity(AValue: TLegendMultiplicity);
     procedure SetOnDraw(AValue: TLegendItemDrawEvent);
+    procedure SetOrder(AValue: Integer);
     procedure SetUserItemsCount(AValue: Integer);
   public
     constructor Create(AOwner: TCustomChart);
@@ -192,12 +197,18 @@ type
   published
     property Multiplicity: TLegendMultiplicity
       read FMultiplicity write SetMultiplicity default lmSingle;
-    property OnDraw: TLegendItemDrawEvent read FOnDraw write SetOnDraw;
+    property Order: Integer
+      read FOrder write SetOrder default LEGEND_ITEM_ORDER_AS_ADDED;
     property UserItemsCount: Integer
       read FUserItemsCount write SetUserItemsCount default 1;
     property Visible default true;
+
+  published
+    property OnDraw: TLegendItemDrawEvent read FOnDraw write SetOnDraw;
   end;
 
+  function LegendItemCompare(AItem1, AItem2: Pointer): Integer;
+
 implementation
 
 uses
@@ -206,6 +217,11 @@ uses
 const
   SYMBOL_TEXT_SPACING = 4;
 
+function LegendItemCompare(AItem1, AItem2: Pointer): Integer;
+begin
+  Result := Sign(TLegendItem(AItem1).Order - TLegendItem(AItem2).Order);
+end;
+
 { TChartLegendItems }
 
 function TChartLegendItems.GetItem(AIndex: Integer): TLegendItem;
@@ -223,6 +239,7 @@ end;
 constructor TLegendItem.Create(const AText: String; AColor: TColor);
 begin
   FColor := AColor;
+  FOrder := LEGEND_ITEM_ORDER_AS_ADDED;
   FText := AText;
 end;
 
@@ -548,6 +565,7 @@ end;
 constructor TChartSeriesLegend.Create(AOwner: TCustomChart);
 begin
   inherited Create(AOwner);
+  FOrder := LEGEND_ITEM_ORDER_AS_ADDED;
   FVisible := true;
   FUserItemsCount := 1;
 end;
@@ -566,6 +584,13 @@ begin
   StyleChanged(Self);
 end;
 
+procedure TChartSeriesLegend.SetOrder(AValue: Integer);
+begin
+  if FOrder = AValue then exit;
+  FOrder := AValue;
+  StyleChanged(Self);
+end;
+
 procedure TChartSeriesLegend.SetUserItemsCount(AValue: Integer);
 begin
   if FUserItemsCount = AValue then exit;