Java中时间序列数据中用户选择的标记

Question

我的代码在面板中绘制了5000个时间序列数据点，默认宽度为581像素，但当用户调整窗口大小时，宽度会发生变化。我的代码还绘制了几个矩形标记，每个标记在相同的空间中标识一个局部最大值/峰值。

我需要让用户右键单击任何矩形峰标记，以便用户可以手动删除任何假峰。问题在于，当用户右键单击峰标记时，我的代码报告的x坐标不同于预期值。我怀疑这个原因可能与将581个x像素转换回5000个数据索引时的舍入误差有关。但我不确定原因。

任何人都可以提出一个解决方案，使我的用户可以通过右键单击来手动选择上述峰值标记之一吗？

我附上下面的代码的相关部分。我的实际代码非常非常长，而且太复杂，无法发布。但是下面的相关部分应该足以让某人看到我的方法的逻辑，然后提出一个更有效的方法。

声明所涉及的类的代码是：

class SineDraw extends JPanel implements MouseMotionListener, MouseListener { 
// lots of code, including the two segments excerpted below 
} 

此代码段重载JPanel的的paintComponent使我的数据绘制：

// declare some variables 
ArrayList<Double> PeakList = new ArrayList<Double>() // this ArrayList is populated by an extraneous process 
visiblePoints = 5000 
hstep = getWidth()/visiblePoints //=581/5000 by default, but will change when user resizes window 
int numPeaks = PeakList.size(); 

// scale (y-coordinate) data relative to height of panel 
pts = new double[visiblePoints] 
for (int i = 0; i < pts.length-1; i++){pts[i]=//data vertical scaled to fill panel;} 

// plot the 5000 time-series-data-points within the 581 pixels in x-axis 
for (int i = 1; i < visiblePoints; i++) { 
    int x1 = (int) ((i - 1) * hstep); 
    int x2 = (int) (i * hstep); 
    int y1 = (int)pts[i - 1]; 
    int y2 = (int)pts[i]; 
    g2.drawLine(x1, y1, x2, y2); 
} 

// plot a rectangle for each of the local peaks 
for(int m=0;m<=(numPeaks-1);m++){ 
    if(i==(int)(PeakList.get(m)){ 
     int currentVal = (int)pts[(int)(PeakList.get(m)]; 
     g2.drawRect((int)(PeakList.get(m), currentVal, 6, 6); 
    } 
} 

这部分代码是用于处理鼠标右击：

public void mousePressed(MouseEvent e){ 
    // check to see if right mouse button was clicked 
    boolean jones = (e.getModifiers()&InputEvent.BUTTON3_MASK)==InputEvent.BUTTON3_MASK; 
    if(jones==true){ 
     // test the value returned as x-coordinate when user right-clicks (code always underestimates x-coordinate of local peaks by this test) 
     double ReverseHstep = visiblePoints/getWidth(); 
     int getX_ConvertedTo_i = (int) (e.getX()*ReverseHstep); 
     System.out.println("getX_ConvertedTo_i is: "+getX_ConvertedTo_i); 

     // check to see if peaklist contains a value within the x-coordinates of the user-selected-rectangle 
     if(PeakList.contains((double)(e.getX()-3)) 
       ||PeakList.contains((double)(e.getX()-2)) 
       ||PeakList.contains((double)(e.getX()-1)) 
       ||PeakList.contains((double)(e.getX())) 
       ||PeakList.contains((double)(e.getX()+1)) 
       ||PeakList.contains((double)(e.getX()+2)) 
       ||PeakList.contains((double)(e.getX()+3)) 
       ){ 
       // handling code will go here, but for now it is a print test that never succeeds because x-coordinate is always underestimated 
       System.out.println("You just selected a peak!"); 
     } 
     } 
    repaint(); 
    } 

Answer 1

我建议你创建对象（在这种情况下Rectangles）你想要点击每件事情。这里是一个过度简化的例子，说明如何让你绘制可点击的东西。关键是要采取的方法是mouseClicked方法，如果鼠标在矩形内单击，将显示对话框只有。

一个棘手的问题是，我无法弄清楚如何用颜色填充矩形而不用在其上绘制另一个矩形。我会离开那一个给你;-)

public class Canvas extends JPanel implements MouseListener{ 
    private Rectangle rect = new Rectangle(100,100); 

    public Canvas(){ 
     this.addMouseListener(this); 
     rect.setSize(100, 100); 
    } 

    @Override 
    public void paintComponent(Graphics g){ 
     g.setClip(rect); 
     g.setColor(Color.RED); 
     g.fillRect(0, 0, 100, 100); 
    } 

    @Override 
    public void mouseClicked(MouseEvent e){ 
     if(rect.contains(e.getPoint())){ 
      JOptionPane.showConfirmDialog(this, "Click!"); 
     } 
    } 

    // The rest of the MouseListener methods have been cut out 

    public static void main(String[] a){ 
     JFrame frame = new JFrame("Canvas Thingy"); 
     frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
     frame.setBounds(0, 0, 300, 300); 
     frame.add(new Canvas()); 
     frame.setVisible(true); 
    } 
}