Android aChartEngine 可移动折线图

Question

我正在使用适用于 Android 的 aChartEngine 的 0.7.0 图表库。谁能帮助我了解如何从左到右绘制折线图并最终移出视图以及如何将图表视图滚动到左侧？

我的代码是....

public class MainActivity extends Activity {

    private GraphicalView view;
    private static Thread thread;
    private TimeSeries dataSet = new TimeSeries("Heart Beat Rate");
    private XYSeriesRenderer renderer = new XYSeriesRenderer();
    private XYMultipleSeriesDataset mDataset = new XYMultipleSeriesDataset();
    private XYMultipleSeriesRenderer mRenderer = new XYMultipleSeriesRenderer();
      @Override
      public void onCreate(Bundle savedInstanceState) {
              super.onCreate(savedInstanceState);
              setContentView(R.layout.main);       
              LinearLayout layout_eeg1 = (LinearLayout) findViewById(R.id.chart1);
                view = getView(this);
                layout_eeg1.addView(view,new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT));
                thread = new Thread() {
                public void run() {
                    for (int i = 0; i < 200; i++) {
                        try {
                            Thread.sleep(500);
                        } catch (InterruptedException e) {
                            e.printStackTrace();
                        } 
                        Point p = getDataFromReciver(i);
                        addNewPoint(p);
                        view.repaint();
                    }
                }
            };
            thread.start(); 

      }      
      private static Point getDataFromReciver(int x) {
        return new Point(x, randomData());
    }

    private static int randomData() {
        Random random = new Random();
        return random.nextInt(180);
    }

    private int x;
    private int y;

    public void Point( int x, int y) {
        this.x = x;
        this.y = y;
    }
    private int getX() {
        return x;
    }   
     private int getY() {
        return y;
    }
      public MainActivity() {
        mDataset.removeSeries(dataSet);
        mDataset.addSeries(dataSet);


        renderer.setColor(Color.GREEN);
        renderer.setLineWidth(2);
        double xmax = mRenderer.getXAxisMax();
        mRenderer.setXAxisMin(xmax - 5);
        //renderer.setPointStyle(PointStyle.SQUARE);
        //renderer.setFillPoints(true);
         mRenderer.setShowAxes(false);
        mRenderer.setShowGridX(false); // X grid helps identify values
        mRenderer.setShowLabels(false); // See the values
        mRenderer.setXTitle("Milisecond #");
        mRenderer.setYTitle("HeartBeat");
        mRenderer.removeSeriesRenderer(renderer);
        mRenderer.addSeriesRenderer(renderer);
        }
      private GraphicalView getView(Context context) {
        view = ChartFactory.getLineChartView(context, mDataset, mRenderer);
        return view;

    }
    private void addNewPoint(Point p) {
        dataSet.add(p.x, p.y);      
    }
}

Answer 1

如果您的图表不使用时间值，那么它应该是直截了当的。如您所知，achartengine 会自动尝试将所有点拟合到一个图形中，以便始终显示右侧。由于您只想控制左侧显示的内容，因此您可以获得最大 x 值，无论它是什么，然后将最小值设置为小于您要显示的间隔。这里的 mrenderer 是 XYMultipleSeriesRenderer

顺便说一句，achartengine 已经将其库升级到 1.0.0

改用这个线程：

    thread = new Thread() {
        public void run() {
            for (int i = 0; i < 200; i++) {
                try {
                    Thread.sleep(500);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
                Point p = getDataFromReciver(i);
                addNewPoint(p);

                if (i > 5) {
                    mRenderer.setXAxisMin(i - 5);
                }

                view.repaint();
            }
        }
    };
    thread.start();