title: Unable to see Apache POI updated data value in BarChart in pptx without editing
body: <p>I have a pptx template, it has just 1 slide for testing purpose. The slide has a simple bar chart. I am able to edit the bar chart by double clicking it on pptx file and I could change the values in Sheet1 (Data sheet for Barchart), and, I able to see the changes immediately in BarChart.</p>
  
  <p>Now, I am trying to do the same using POI API. I am doing the below steps here</p>
  
  <ol>
  <li>Read the template file = "MyTemplate.pptx" - <a href="https://docs.google.com/file/d/0B-q0lBy0lKLic3dCSUVsZUdGQzA/edit?usp=sharing" rel="nofollow">https://docs.google.com/file/d/0B-q0lBy0lKLic3dCSUVsZUdGQzA/edit?usp=sharing</a></li>
  <li>Have all shapes in Map</li>
  <li>Read the BarChart shape by referring it's name - "MyBarChart"</li>
  <li>Read the excel file of the BarChart</li>
  <li>Update a cell Value in Sheet1</li>
  <li>Save everything and write into another file - "MyPresentation.pptx"</li>
  </ol>
  
  <p>When I open the file - "MyPresentation.pptx", it does not show up the updated cell value upfront in the Bar. I need to double click the chart to change it to EDIT mode to get the latest value reflected. Why does BarChart is not getting refreshed when it's underlying Data Sheet is updated using POI?</p>
  
  <p>Any suggestion to solve the issue?</p>
  
  <p>Here is the completed code, attached pptx template file as well.</p>
  
  <pre><code>package com.ppt;
  
  import java.io.FileInputStream;
  import java.io.FileOutputStream;
  import java.io.IOException;
  import java.io.OutputStream;
  import java.util.HashMap;
  import java.util.Map;
  
  import org.apache.poi.hssf.usermodel.HSSFRow;
  import org.apache.poi.hssf.usermodel.HSSFSheet;
  import org.apache.poi.hssf.usermodel.HSSFWorkbook;
  import org.apache.poi.openxml4j.exceptions.InvalidFormatException;
  import org.apache.poi.openxml4j.opc.PackagePart;
  import org.apache.poi.xslf.usermodel.XMLSlideShow;
  import org.apache.poi.xslf.usermodel.XSLFGraphicFrame;
  import org.apache.poi.xslf.usermodel.XSLFShape;
  import org.apache.poi.xslf.usermodel.XSLFSheet;
  import org.apache.poi.xslf.usermodel.XSLFSlide;
  
  public class PPTChart {
  
      public static void main(String args[]) throws InvalidFormatException, IOException{ 
  
          XMLSlideShow ppt;
  
          // Read pptx template
          ppt = new XMLSlideShow(new FileInputStream("MyTemplate.pptx"));
  
          // Get all slides
          XSLFSlide[] slide = ppt.getSlides();
  
          // Get working slide that is slide=0
          XSLFSlide slide0 = slide[0];
          XSLFShape[] shapes = slide0.getShapes();
  
          // Add all shapes into a Map
          Map &lt;String, XSLFShape&gt; shapesMap = new HashMap&lt;String, XSLFShape&gt;();
          for(XSLFShape shape : shapes)
          {
              shapesMap.put(shape.getShapeName(), shape);
              System.out.println(shape.getShapeName() + "  " + shape.getShapeId() + "   " + shape);
  
          }
  
          // Read the bar chart
          XSLFGraphicFrame chart = (XSLFGraphicFrame) shapesMap.get("MyBarChart");
  
          // Get the chart sheet
          XSLFSheet sheet =  chart.getSheet();
  
          for(int i=0; i&lt;sheet.getRelations().size(); i++)
          {
              System.out.println("Partname =" + sheet.getRelations().get(i).getPackagePart().getPartName());
  
  
  
              if(sheet.getRelations().get(i).getPackagePart().getPartName().toString().contains(".xls"))
              {
  
                  System.out.println("Found the bar chart excel");
  
                  // BarChart Excel package part
                  PackagePart barChartExcel  = sheet.getRelations().get(i).getPackagePart();
  
                  // Reference the excel in workbook
                  HSSFWorkbook wb = new HSSFWorkbook(barChartExcel.getInputStream());
  
                  // Read sheet where Barchart data is available
                  HSSFSheet mysheet =  wb.getSheetAt(1);
  
                  // Read first
                  HSSFRow row = mysheet.getRow(1);
  
  
                  //Print first cell value for debugging
                  System.out.println("Updating cell value from - " + row.getCell(1));
  
                  // New value
                  double insertValue = 7777777.0;
  
  
                  wb.getSheetAt(1).getRow(1).getCell(1).setCellValue(insertValue);
  
                  // Set first BarChart as active sheet
                  HSSFSheet mysheet0 =  wb.getSheetAt(0);
                  mysheet0.setActive(true);
  
                  // Write the updated excel back to workbook
                  OutputStream excelOut = barChartExcel.getOutputStream();
                  excelOut.flush();
                  wb.write(excelOut);
                  excelOut.close();
  
                  // Write workbook to file
                  FileOutputStream o = new FileOutputStream("MyPresentation.pptx");
                  ppt.write(o);
                  o.close();
                  System.out.println("new ppt is created....");
  
                  break; // Exit
              }
  
          }
      }
  }
  </code></pre>