Steema Central

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procedure TForm1.FormCreate(Sender: TObject);
var i,j : Integer;
begin
  InitChart;

  for i:=0 to Chart1.SeriesCount-1 do
    InitSeries(Chart1[i]);

  for j:=0 to Series1.Count-1 do
    Series1.XLabel[j] := DateTimeToStr(now);

  //You'll need to refresh the grid if setting labels separately.
  //ChartGrid1.Refresh;

  ChartGrid1.ShowXValues:=cgsNo;
  ChartGrid1.ShowLabels:=true;
end;

procedure TForm1.InitSeries(ASeries: TChartSeries);
Var X,Y : Array of Double;   // TChartValues
    t   : Integer;
    Num : Integer;
begin
  With (ASeries as TFastLineSeries) do
  begin
    FastPen:=true;
    DrawAllPoints:=false;
    AutoRepaint:=false;
    LinePen.OwnerCriticalSection := nil;
  end;

  Num:= 500000;

  { allocate our custom arrays }
  SetLength(X,Num);
  SetLength(Y,Num);

  { fill data in our custom arrays }
  X[0]:=0;
  Y[0]:=Random(10000);
  for t:=1 to Num-1 do
  begin
    X[t]:=t;
    Y[t]:=Y[t-1]+Random(101)-50;
  end;

  { set our X array }
  With ASeries.XValues do
  begin
    Value:=TChartValues(X);  { <-- the array }
    Count:=Num;               { <-- number of points }
    Modified:=True;           { <-- recalculate min and max }
  end;

  { set our Y array }
  With ASeries.YValues do
  begin
    Value:=TChartValues(Y);
    Count:=Num;
    Modified:=True;
  end;

  { Show data }
  Series1.Repaint;
end;

procedure TForm1.InitChart;
begin
  with Chart1 do
  begin
    ClipPoints := False;
    Title.Visible := False;
    Legend.Visible := False;
    With Axes do
    begin
      Left.Axis.Width:=1;
      Bottom.Axis.Width:=1;
      Bottom.RoundFirstLabel := False;
      FastCalc := True;
    end;
    View3D := False;
    Canvas.ReferenceCanvas.Pen.OwnerCriticalSection := nil;
  end;
end;