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</o:shapelayout></xml><![endif]--></head><body lang=ES-PE link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span lang=EN-US style='color:#0070C0'>Hi All, I found a possible Bug in TAChart component. Lazarus v0.9.30.1 SVN:3056 on Windows 7 x64<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:#0070C0'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:#0070C0'>Create a Project with a TChart and TButton controls, add a TLineseries and TUserDefinedChartSource with some points, select the last one as source for the serie. Define a Var array of real and assign values to the array on the Tbutton onclick event. Populate the AItem values with the data in the array. Sometimes when I zoom the chart the serie is not redrawing. (The example project is not attached because size limit of the message). Make a zoom on the second point [0.1,0.5] but without include the zero Y axis value, the serie is not drawing but if the zero level is included in the zoom then the serie is drawing correctly)<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Courier New"'> TForm1 = class(TForm)<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Courier New"'> Button1: TButton;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Courier New"'> Chart1: TChart;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Courier New"'> Chart1LineSeries1: TLineSeries;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Courier New"'> DataSource: TUserDefinedChartSource;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Courier New"'> procedure Button1Click(Sender: TObject);<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Courier New"'> procedure DataSourceGetChartDataItem(ASource: TUserDefinedChartSource;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Courier New"'> AIndex: Integer; var AItem: TChartDataItem);<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Courier New"'> end;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Courier New"'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Courier New"'>var<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Courier New"'> Form1: TForm1;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Courier New"'> dat:array [0..3] of real;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Courier New"'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Courier New"'>implementation<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Courier New"'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Courier New"'>{$R *.lfm}<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Courier New"'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Courier New"'>{ TForm1 }<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Courier New"'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Courier New"'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Courier New"'>procedure TForm1.Button1Click(Sender: TObject);<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Courier New"'>begin<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Courier New"'> DataSource.BeginUpdate;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Courier New"'> dat[0]:=0;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Courier New"'> dat[1]:=0.5;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Courier New"'> dat[2]:=0;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Courier New"'> dat[3]:=-0.5;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Courier New"'> DataSource.EndUpdate;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Courier New"'>end;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Courier New"'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Courier New"'>procedure TForm1.DataSourceGetChartDataItem(ASource: TUserDefinedChartSource;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Courier New"'> AIndex: Integer; var AItem: TChartDataItem);<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Courier New"'>begin<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Courier New"'> AItem.X:=AIndex/10;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Courier New"'> AItem.Y:=dat[AIndex];<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:8.0pt;font-family:"Courier New"'>end;<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:#0070C0'>Thank you.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:#0070C0'> <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p></div></body></html>