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delphivclteechart

TeeChart CalcClickedPart Bug after Marks.Item[nPoint].Visible :=false

Delphi 10.1 Pro, VCL with embedded Teechart controls. CalcClickedPart shows cpSeriesMarks after a Marks set to be hidden at the place it was previously shown.

I may not deleting Marks correctly, only hiding it, or there is a bug in CalcClickedPart. Please advice.

I added a tLabel on the top-left which show the CalcClickedPart Part result. Also a button to toggle the Marks visibility.

The series & Marks creation:

procedure TForm2.FormCreate(Sender: TObject);
var i: Integer;
begin
  Chart1.View3D:=false;
  with Chart1.AddSeries(TLineSeries) as TLineSeries do
    begin
      for i := 0 to 9 do
        begin
          AddXY(i, 10);
          Marks.Item[i].Visible := false; // Hide all Marks
        end;

      Marks.Show; // A global Marks enabled.
      Marks.Item[5].Visible := true;
    end;
end;

CalcClickedPart test:

procedure TForm2.Chart1MouseMove(Sender: TObject; Shift: TShiftState; X,
  Y: Integer);
Var
  ClickedPart: tChartClickedPart;
  sCursorText: string;
begin
  sCursorText := '';

  Chart1.CalcClickedPart(Point(X, Y), ClickedPart); // Return information about the TeeChart component below the Mouse pointer at an X,Y location.
  Case ClickedPart.Part of
    cpNone          : sCursorText := 'cpNone';
    cpLegend        : sCursorText := 'cpLegend';
    cpAxis          : sCursorText := 'cpAxis';
    cpSeries        : sCursorText := 'cpSeries';
    cpTitle         : sCursorText := 'cpTitle';
    cpFoot          : sCursorText := 'cpFoot';
    cpChartRect     : sCursorText := 'cpChartRect';
    cpSeriesMarks   : sCursorText := 'cpSeriesMarks';
    cpSeriesPointer : sCursorText := 'cpSeriesPointer ';
    cpSubTitle      : sCursorText := 'cpSubTitle';
    cpSubFoot       : sCursorText := 'cpSubFoot';
    cpAxisTitle     : sCursorText := 'cpAxisTitle';
  end;

  Label1.Caption := sCursorText;
end;

The Marks visibility toggling:

procedure TForm2.btnMarksToggleClick(Sender: TObject);
begin
  with (Chart1[0] as tLineSeries).Marks.Item[5] do
    Visible := not Visible;
end;

Marks is visible. A correct cpSeriesMarks (cursor in Red arrow):

Press the button to hide the Marks. Will get the following wrong CalcClickedPart. Marks is NOT visible. An incorrect cpSeriesMarks (cursor in Red arrow):

Do you have any idea for work around?

p.s I previously found a bug with CalcClickedPart when CalcVisiblePoints := false. This is another issue, not related to CalcVisiblePoints at all.

Thanks Reron

Solution

  • I've been able to reproduce the problem here so I've added it to the public tracker (#2092).

    Note the problem is at TSeriesMarks.Clicked function.
    I've already fixed it for the next versions.

    As a workaround, you could set Positions.Item[5]:=nil:

    procedure TForm2.btnMarksToggleClick(Sender: TObject);
const aMarksIndex = 5;
begin
  with (Chart1[0] as tLineSeries).Marks do
  begin
    with Item[aMarksIndex] do
      Visible := not Visible;

    if not Item[aMarksIndex].Visible then
       Positions.Items[aMarksIndex]:=nil;
  end;
end;