From 267a457efe0aff1ee69d565ae99117ed47f99043 Mon Sep 17 00:00:00 2001
From: ask <ask@lazarus-ide.org>
Date: Tue, 12 Jul 2011 09:22:52 +0000
Subject: [PATCH] TAChart: Add and use TLegendItemsEnumerator

git-svn-id: trunk@31674 -
---
 components/tachart/demo/legend/main.pas |  4 +--
 components/tachart/tachartlistbox.pas   |  6 ++---
 components/tachart/talegend.pas         | 36 ++++++++++++++++++-------
 3 files changed, 32 insertions(+), 14 deletions(-)

diff --git a/components/tachart/demo/legend/main.pas b/components/tachart/demo/legend/main.pas
index 51d6d1846a..b13d1ada5e 100644
--- a/components/tachart/demo/legend/main.pas
+++ b/components/tachart/demo/legend/main.pas
@@ -115,13 +115,13 @@ end;
 
 procedure TForm1.FormCreate(Sender: TObject);
 var
-  i: Integer;
+  li: TLegendItem;
 begin
   // Workaround for issue #19632
   Chart1FuncSeries1.Legend.OnCreate := @Chart1FuncSeries1LegendCreate;
   FItems := Chart1.GetLegendItems;
   Chart1.Legend.SortItemsByOrder(FItems);
-  for i := 1 to FItems.Count do
+  for li in FItems do
     cbSeries.AddItem('', nil);
 end;
 
diff --git a/components/tachart/tachartlistbox.pas b/components/tachart/tachartlistbox.pas
index 4b0c15b5a5..fcab5bcc32 100644
--- a/components/tachart/tachartlistbox.pas
+++ b/components/tachart/tachartlistbox.pas
@@ -460,7 +460,7 @@ procedure TChartListbox.Populate;
 { populates the listbox with all series contained in the chart. Use the event
   OnPopulate if you don't omit special series from the listbox (RemoveSeries) }
 var
-  i: Integer;
+  li: TLegendItem;
 begin
   Items.BeginUpdate;
   try
@@ -469,9 +469,9 @@ begin
     FreeAndNil(FLegendItems);
     FLegendItems := CreateLegendItems;
     Chart.Legend.SortItemsByOrder(FLegendItems);
-    for i := 0 to FLegendItems.Count - 1 do
+    for li in FLegendItems do
       // The caption is owner-drawn, but add it anyway for user convenience.
-      Items.AddObject(FLegendItems[i].Text, FLegendItems[i]);
+      Items.AddObject(li.Text, li);
     if Assigned(OnPopulate) then
       OnPopulate(Self);
   finally
diff --git a/components/tachart/talegend.pas b/components/tachart/talegend.pas
index 8792984438..3dba1c2021 100644
--- a/components/tachart/talegend.pas
+++ b/components/tachart/talegend.pas
@@ -111,6 +111,12 @@ type
     procedure Draw(ADrawer: IChartDrawer; const ARect: TRect); override;
   end;
 
+  TLegendItemsEnumerator = class(TListEnumerator)
+  public
+    function GetCurrent: TLegendItem;
+    property Current: TLegendItem read GetCurrent;
+  end;
+
   { TChartLegendItems }
 
   TChartLegendItems = class(TObjectList)
@@ -118,6 +124,7 @@ type
     function GetItem(AIndex: Integer): TLegendItem;
     procedure SetItem(AIndex: Integer; AValue: TLegendItem);
   public
+    function GetEnumerator: TLegendItemsEnumerator;
     property Items[AIndex: Integer]: TLegendItem
       read GetItem write SetItem; default;
   end;
@@ -275,8 +282,20 @@ begin
     Result := Sign(li1.Order - li2.Order);
 end;
 
+{ TLegendItemsEnumerator }
+
+function TLegendItemsEnumerator.GetCurrent: TLegendItem;
+begin
+  Result := TLegendItem(inherited GetCurrent);
+end;
+
 { TChartLegendItems }
 
+function TChartLegendItems.GetEnumerator: TLegendItemsEnumerator;
+begin
+  Result := TLegendItemsEnumerator.Create(Self);
+end;
+
 function TChartLegendItems.GetItem(AIndex: Integer): TLegendItem;
 begin
   Result := TLegendItem(inherited GetItem(AIndex));
@@ -517,19 +536,18 @@ end;
 function TChartLegend.MeasureItem(
   ADrawer: IChartDrawer; AItems: TChartLegendItems): TPoint;
 var
-  i: Integer;
   p: TPoint;
   prevFont: TFont = nil;
+  li: TLegendItem;
 begin
   Result := Point(0, 0);
-  for i := 0 to AItems.Count - 1 do
-    with AItems[i] do begin
-      AItems[i].UpdateFont(ADrawer, prevFont);
-      p := ADrawer.TextExtent(Text);
-      if HasSymbol then
-        p.X += SYMBOL_TEXT_SPACING + SymbolWidth;
-      Result := MaxPoint(p, Result);
-    end;
+  for li in AItems do begin
+    li.UpdateFont(ADrawer, prevFont);
+    p := ADrawer.TextExtent(li.Text);
+    if li.HasSymbol then
+      p.X += SYMBOL_TEXT_SPACING + SymbolWidth;
+    Result := MaxPoint(p, Result);
+  end;
 end;
 
 procedure TChartLegend.Prepare(