java - Android aChartEngine条形图不起作用

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);
        setContentView(R.layout.nextstatschart);

        myDataset = new XYMultipleSeriesDataset ();

        statsRenderer = new DefaultRenderer();


        myRenderer.setLabelsColor(Color.BLUE);
        myRenderer.setLabelsTextSize(12);
        myRenderer.setAxesColor(Color.BLACK);
        myRenderer.setBackgroundColor(Color.WHITE);
        myRenderer.setAntialiasing(true);
        myRenderer.setShowLabels(true);
        myRenderer.setShowGrid(true);
        myRenderer.setChartTitle("Next Three Months Statistical Analysis");
        myRenderer.setChartTitleTextSize(16);
        myRenderer.setZoomEnabled(true);

         myRenderer.setChartTitle(heading);
         myRenderer.setLabelsColor(Color.BLACK);
         myRenderer.setXAxisMin(0);
         myRenderer.setXAxisMax(100);
         myRenderer.setYAxisMin(0);
         myRenderer.setYAxisMax(100);
         myRenderer.setYLabelsAlign(Align.RIGHT);
         myRenderer.setXTitle ("Case Type");
         myRenderer.setYTitle ("Count");
         myRenderer.setMargins(new int[] { 30, 40, 10, 40 });




        Bundle b = getIntent().getExtras();
        typ = b.getStringArray("typ");
        nums = b.getStringArray("counts");
        percentages = b.getDoubleArray("percs");
        stat_count = b.getInt("stat_count");
        X_Axis = b.getDoubleArray("typp");
        Y_Axis = b.getDoubleArray("contt");


        }

    @Override
    protected void onResume() {

        super.onResume();

        try {

        refreshChart();

        if (statsChartView == null) {
            LinearLayout layout = (LinearLayout) findViewById(R.id.statschart);
//          statsChartView = ChartFactory.getPieChartView(getApplicationContext(), statsSeries, statsRenderer);
//          statsChartView = ChartFactory.getLineChartView(getApplicationContext(), xyDataset, xyRender);
//          statsChartView = ChartFactory.getBarChartView(context, dataset, renderer, type)

            statsChartView = ChartFactory.getBarChartView(getApplicationContext(), myDataset, myRenderer,Type.DEFAULT);
            layout.addView(statsChartView, new LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT));
            layout.addView(statsChartView);
            statsChartView.refreshDrawableState();

            statsChartView.setBackgroundColor(Color.WHITE);


        } else {
            statsChartView.repaint();
        }
    //  refreshChart();
    }catch(Exception e){
        e.printStackTrace();
    }
}

    void refreshChart() {

        try {

             mySeries = new XYSeries (series);



                int[] colorpool = new int[] { 0xff000099, 0xff009900, 0xffff0000,
                        0xffffff00, 0xff990099, 0xffff9900, 0xff996600, 0xffcccccc,
                        0xff990000, 0xff66cccc, 0xff99ccff, 0xffccffcc };
                int[] colors = new int[stat_count];

             DecimalFormat Currency = new DecimalFormat("#0.00");

                for (int i = 0; i < stat_count; i++) {

                    mySeries.add(Double.parseDouble(typ[i]),Double.parseDouble(nums[i]));

                    if (i > 11) {
                        colors[i] = 0xff333333;
                    } else {
                        colors[i] = colorpool[i];
                    }

                }
                myDataset.addSeries (mySeries);

                for (int color : colors) {
                    SimpleSeriesRenderer r = new SimpleSeriesRenderer();
                    r.setColor(color);
//                  statsRenderer.addSeriesRenderer(r);
                    xyRender.addSeriesRenderer(r);

                }



                mySeriesRenderer = new XYSeriesRenderer ();

                if (series.equals("Weight")) {
                    mySeriesRenderer.setColor (0xff009900);
                    mySeriesRenderer.setPointStyle(PointStyle.POINT);
                } else {
                    mySeriesRenderer.setColor (0xff990099);
                }


                myRenderer.addSeriesRenderer (mySeriesRenderer);
                int length = myRenderer.getSeriesRendererCount();
                for (int i = 0; i < length; i++) {
                    ((XYSeriesRenderer) myRenderer.getSeriesRendererAt(i)).setFillPoints(true);
                }



                //  Draw the chart
                statsChartView.repaint ();
            } catch (Exception e) {
                e.printStackTrace();
                //Exception Code
            }

    }
}

E/AndroidRuntime(910): FATAL EXCEPTION: main
E/AndroidRuntime(910): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.courts.action/com.courts.action.NextStatsChart}: java.lang.NullPointerException

最佳答案

可能是因为这个原因

<activity android:name="com.courts.action.NextStatsChart" android:label="@string/app_name" />

关于java - Android aChartEngine条形图不起作用，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/13739093/