How to set String value of date time on xAxis BarChart MPAndroidChart

Question

I\'m trying to show date time on X-Axis for my bar chart. I got this data from my UNIX timestamp firebase database. I have been trying to convert this UNIX timestamp to a human-

Answer 1

I added an index for x values as I said 0,1,3,4,5.. Then I created a list for the dates.

@Override
public void onDataChange(@NonNull DataSnapshot dataSnapshot) {
     int count_test = 1;
     int index = 0;
     ArrayList<BarEntry> dataValue = new ArrayList<BarEntry>();
     ArrayList<Long> dateList = new ArrayList< Long >();
     if(dataSnapshot.hasChildren()){
           for (DataSnapshot myDataSnapshot : dataSnapshot.getChildren()){
               datapoint DataPoint = myDataSnapshot.getValue(datapoint.class);
               originalTimestamp = DataPoint.getDate();
               dataValue.add(new BarEntry(index, DataPoint.getValue()));
               referenceTimestamp = 1587772800;
               convertedTimestamp = originalTimestamp - referenceTimestamp;
               dateList.add(convertedTimestamp);
               index++;
           }
         showChart(dataValue, dateList);

      } else {
          chart.clear();
          chart.invalidate();
      }
  }

I changed the formatter to use the dateList:

public class FooFormatter extends ValueFormatter {

private ArrayList<Long> dateList; // minimum timestamp
private DateFormat mDataFormat;
private Date mDate;

public FooFormatter(ArrayList<Long>  dateList) {
    dateList = dateList;
    this.mDataFormat = new SimpleDateFormat( "HH:mm", Locale.ENGLISH );
    this.mDate = new Date();
}

@Override
public String getFormattedValue(float value) {
    if((int) value < 0 || (int)(value) > longArrayList.size() -1)
        return "";

    // Retrieve original timestamp
    long originalTimestamp = dateList(((int)value));

    // Convert timestamp
    return getDateString(originalTimestamp);
}

private String getDateString(long timestamp) {
    try {
        mDate.setTime(timestamp * 1000);
        return mDataFormat.format(mDate);
    } catch(Exception ex) {
        return "xx";
    }
}

}

axisValueFormatter

FooFormatter axisValueFormatter = new FooFormatter(dateList);