[Android Charts] onChartValueSelectedListener for MPAndroidChart 三變化

IDE：Android Studio 2.2.2

Chart：MPAndroidChart (Open source) 畫圖前要先洗手，免得弄髒紙:)

 Chart的作者及教學 ，2016年11月原作者還有在更新。

這邊要分享的是將MPAndroidChart 的onChartValueSelectedListener，做出三種變化。

Example 1

private void initPieChart(final PieChart pieChart) {
    initBaseChart(pieChart);

    pieChart.setDrawSliceText(false);
    pieChart.setUsePercentValues(true);
    pieChart.setHoleRadius(45);
    pieChart.setTransparentCircleRadius(50);
    pieChart.setHoleColorTransparent(true);
    pieChart.setRotationEnabled(false);
    pieChart.setRotationAngle(180);

    pieChart.setOnChartValueSelectedListener(new OnChartValueSelectedListener() {
        @Override
        public void onValueSelected(Entry entry, int i, Highlight h) {
            if (entry instanceof EctsEntry) {
                float ects = ((EctsEntry) entry).getEcts();
                if (ects > 0) {
                    pieChart.setDrawCenterText(true);
                    pieChart.setCenterText(String.format("%.2f\nECTS", ects));
                }
            }
        }

        @Override
        public void onNothingSelected() {
            pieChart.setDrawCenterText(false);
        }
    });

    if (pieChart.getRenderer() != null) {
        ((PieChartRenderer) pieChart.getRenderer()).getPaintCenterText().setColor(mTextColorPrimary);
    }
}
 

Example 2

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

 // Init data storage:
 batteryData = new BatteryData();

 // Load prefs:
 appPrefes = new AppPrefes(getActivity(), "ovms");

 mShowVolt = appPrefes.getData("battery_show_volt").equals("on");
 mShowTemp = appPrefes.getData("battery_show_temp").equals("on");
 if (!mShowVolt && !mShowTemp)
  mShowVolt = true;


 // Setup UI:
 ProgressOverlay progressOverlay = createProgressOverlay(inflater, container, false);
 progressOverlay.setOnCancelListener(this);

 View rootView = inflater.inflate(R.layout.fragment_battery, null);


 //
 // Setup Cell status chart:
 //

 XAxis xAxis;
 YAxis yAxis;

 cellChart = (CandleStickChart) rootView.findViewById(R.id.chart_cells);
 cellChart.setDescription(getString(R.string.battery_cell_description));
 cellChart.getPaint(LineChart.PAINT_DESCRIPTION).setColor(Color.LTGRAY);
 cellChart.setDrawGridBackground(false);
 cellChart.setDrawBorders(true);

 xAxis = cellChart.getXAxis();
 xAxis.setTextColor(Color.WHITE);

 yAxis = cellChart.getAxisLeft();
 yAxis.setTextColor(COLOR_VOLT);
 yAxis.setGridColor(COLOR_VOLT_GRID);
 yAxis.setStartAtZero(false);
 yAxis.setValueFormatter(new ValueFormatter() {
  @Override
  public String getFormattedValue(float v) {
   return String.format("%.2f", v);
  }
 });

 yAxis = cellChart.getAxisRight();
 yAxis.setTextColor(COLOR_TEMP);
 yAxis.setGridColor(COLOR_TEMP_GRID);
 yAxis.setStartAtZero(false);
 yAxis.setValueFormatter(new ValueFormatter() {
  @Override
  public String getFormattedValue(float v) {
   return String.format("%.0f", v);
  }
 });


 //
 // Setup Pack history chart:
 //

 packChart = (LineChart) rootView.findViewById(R.id.chart_pack);
 packChart.setDescription(getString(R.string.battery_pack_description));
 packChart.getPaint(LineChart.PAINT_DESCRIPTION).setColor(Color.LTGRAY);
 packChart.setDrawGridBackground(false);
 packChart.setDrawBorders(true);
 packChart.setOnChartValueSelectedListener(new OnChartValueSelectedListener() {
  @Override
  public void onValueSelected(Entry entry, int dataSet, Highlight highlight) {
   // remember user data set selection:
   highlightSetNr = dataSet;
   highlightSetLabel = packChart.getData().getDataSetByIndex(dataSet).getLabel();

   // update seek bar:
   seekPack.setProgress(entry.getXIndex()); // fires listener event (fromUser=false)

   // update cell chart:
   showCellStatus(entry.getXIndex());
  }

  @Override
  public void onNothingSelected() {
   // nop
  }
 });

 xAxis = packChart.getXAxis();
 xAxis.setTextColor(Color.WHITE);

 yAxis = packChart.getAxisLeft();
 yAxis.setStartAtZero(false);
 yAxis.setSpaceTop(5f);
 yAxis.setSpaceBottom(5f);
 yAxis.setTextColor(COLOR_SOC_TEXT);
 yAxis.setGridColor(COLOR_SOC_GRID);
 yAxis.setValueFormatter(new ValueFormatter() {
  @Override
  public String getFormattedValue(float v) {
   return String.format("%.0f%%", v);
  }
 });

 yAxis = packChart.getAxisRight();
 yAxis.setStartAtZero(false);
 yAxis.setSpaceTop(15f);
 yAxis.setSpaceBottom(15f);
 yAxis.setTextColor(COLOR_VOLT);
 yAxis.setGridColor(COLOR_VOLT_GRID);
 yAxis.setValueFormatter(new ValueFormatter() {
  @Override
  public String getFormattedValue(float v) {
   return String.format("%.0f", v);
  }
 });


 //
 // Setup Pack history seek bar:
 //

 seekPack = (SeekBar) rootView.findViewById(R.id.seek_pack);
 seekPack.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
  @Override
  public void onProgressChanged(SeekBar seekBar, int val, boolean fromUser) {
   if (fromUser) {
    // highlight entry:
    highlightPackEntry(val);

    // update cell chart:
    showCellStatus(val);
   }
  }

  @Override
  public void onStartTrackingTouch(SeekBar seekBar) {
   // nop
  }

  @Override
  public void onStopTrackingTouch(SeekBar seekBar) {
   // nop
  }
 });

 // default data set to highlight:
 highlightSetLabel = getString(R.string.battery_data_soc);

 // attach menu:
 setHasOptionsMenu(true);

 return rootView;
}

Example 3

void initializeChart() {
    Resources r = getResources();
    int CgpaColor ;
    if(Cgpa>8.0f)
        CgpaColor = r.getColor(R.color.highAttend);
    else if(Cgpa>6.0f&&Cgpa<8 .0f="" arraylist="" cgpacolor="r.getColor(R.color.lowAttend);" else="" ntry=""> data = new ArrayList<>();
    ArrayList CGPAentryList = new ArrayList<>();
    float maxGpa = 0.0f, minGpa = 10.0f;
    ArrayList xVals = new ArrayList<>();
    for (int i = 0; i < semesterWiseGrades.size(); i++) {
        float gpa = (float) semesterWiseGrades.get(i).getGpa();
        xVals.add(getString(R.string.label_semester_no, i + 1));
        data.add(new Entry(gpa, i));
        if (gpa > maxGpa)
            maxGpa = gpa;
        if (gpa < minGpa)
            minGpa = gpa;
    }
    CGPAentryList.add(new Entry(Cgpa,0));
    CGPAentryList.add(new Entry(Cgpa,data.size()-1));
    LineDataSet dset = new LineDataSet(data, getString(R.string.label_grade_gpa));
    LineDataSet CGPAdset = new LineDataSet(CGPAentryList,"CGPA " + String.valueOf(Cgpa));
    CGPAdset.setDrawCircleHole(false);
    CGPAdset.setHighlightEnabled(false);
    CGPAdset.setDrawFilled(true);
    CGPAdset.setFillAlpha(80);
    CGPAdset.enableDashedLine(1.0f,0.5f,0.5f);
    CGPAdset.setDrawCircles(false);
    CGPAdset.setDrawValues(false);
    dset.setLineWidth(2.0f);CGPAdset.setLineWidth(1.0f);
    dset.setValueTextSize(10.0f);CGPAdset.setValueTextSize(10.0f);
    dset.setColor(r.getColor(R.color.colorPrimary));CGPAdset.setColor(CgpaColor);
    CGPAdset.setFillColor(CgpaColor);
    dset.setHighLightColor(r.getColor(R.color.colorPrimary));
    dset.setCircleColor(r.getColor(R.color.colorAccent));
    dset.setDrawCircleHole(false);
    LineData chartData = new LineData(xVals, Arrays.asList(dset,CGPAdset));
    YAxis leftaxis = chart.getAxisLeft();
    leftaxis.setStartAtZero(false);
    leftaxis.setAxisMinValue(minGpa - 0.1f);
    leftaxis.setAxisMaxValue(maxGpa + 0.1f);
    chart.setDescription("");
    YAxis rightAxis = chart.getAxisRight();
    leftaxis.setEnabled(false);
    rightAxis.setEnabled(false);
    chart.getXAxis().setEnabled(false);
    chart.setData(chartData);
    chart.setPinchZoom(false);
    chart.setDoubleTapToZoomEnabled(false);
    chart.highlightValue(0, 0);
    chart.setOnChartValueSelectedListener(new OnChartValueSelectedListener() {
        @Override
        public void onValueSelected(Entry e, int dataSetIndex, Highlight h) {
            pager.setCurrentItem(e.getXIndex());
        }

        @Override
        public void onNothingSelected() {
            pager.setCurrentItem(0);
        }
    });
}