JListから長方形を描く方法選択

Question

私が書いているJavaプログラムに関する助けを探しています。私は、JListの選択イベントによって生成された配列に保存されたデータに基づいて矩形で構成される単純な棒グラフを表示する必要があります。しかし、JPanelには何も描かれておらず、私はそれを修正する方法を理解できません。

try 
{ 
BufferedReader in = new BufferedReader((new FileReader("scores.txt"))); 

String sLine; 

while ((sLine = in.readLine()) != null) 
{ 
    vecAthlete.addElement(new Stage3_DataFile(sLine)); 
} 

String[] saAthlete = new String[vecAthlete.size()]; 
for (int iI = 0; iI < vecAthlete.size(); iI++) 
    saAthlete[iI] = vecAthlete.get(iI).sName; 
jList_Athlete.setListData(saAthlete); 
jList_Athlete.setSelectedIndex(0); 

// Reading input line by line 
// Close file 
    in.close(); 
} 
catch (IOException e) 
{ 
    System.out.println("ERROR: Could not read text file!"); 
} 
jList_Athlete.addListSelectionListener(new javax.swing.event.ListSelectionListener() 
{ 
    public void valueChanged(javax.swing.event.ListSelectionEvent e) 
    { 
     double[][] daRun = new double[2][7]; 

     final double dScoreUsed = 5; 
     double dMinScoreRun1 = 10, dMaxScoreRun1 = 0; 
     double dMinScoreRun2 = 10, dMaxScoreRun2 = 0; 

     double dTotalRun1 = 0, dTotalRun2 = 0; 

     jLabel_Athlete.setText(vecAthlete.get(jList_Athlete.getSelectedIndex()).sName); 
     jLabel_Country.setText(vecAthlete.get(jList_Athlete.getSelectedIndex()).sCountry); 

     jLabel_Run1_Score_1.setText(vecAthlete.get(jList_Athlete.getSelectedIndex()).saTempRun1[0]); 
    jLabel_Run1_Score_2.setText(vecAthlete.get(jList_Athlete.getSelectedIndex()).saTempRun1[1]); 
    jLabel_Run1_Score_3.setText(vecAthlete.get(jList_Athlete.getSelectedIndex()).saTempRun1[2]); 
    jLabel_Run1_Score_4.setText(vecAthlete.get(jList_Athlete.getSelectedIndex()).saTempRun1[3]); 
    jLabel_Run1_Score_5.setText(vecAthlete.get(jList_Athlete.getSelectedIndex()).saTempRun1[4]); 
    jLabel_Run1_Score_6.setText(vecAthlete.get(jList_Athlete.getSelectedIndex()).saTempRun1[5]); 
    jLabel_Run1_Score_7.setText(vecAthlete.get(jList_Athlete.getSelectedIndex()).saTempRun1[6]); 

    jLabel_Run2_Score_1.setText(vecAthlete.get(jList_Athlete.getSelectedIndex()).saTempRun2[0]); 
    jLabel_Run2_Score_2.setText(vecAthlete.get(jList_Athlete.getSelectedIndex()).saTempRun2[1]); 
    jLabel_Run2_Score_3.setText(vecAthlete.get(jList_Athlete.getSelectedIndex()).saTempRun2[2]); 
    jLabel_Run2_Score_4.setText(vecAthlete.get(jList_Athlete.getSelectedIndex()).saTempRun2[3]); 
    jLabel_Run2_Score_5.setText(vecAthlete.get(jList_Athlete.getSelectedIndex()).saTempRun2[4]); 
    jLabel_Run2_Score_6.setText(vecAthlete.get(jList_Athlete.getSelectedIndex()).saTempRun2[5]); 
    jLabel_Run2_Score_7.setText(vecAthlete.get(jList_Athlete.getSelectedIndex()).saTempRun2[6]); 


    daRun[0][0] = Double.parseDouble(jLabel_Run1_Score_1.getText()); 
    daRun[0][1] = Double.parseDouble(jLabel_Run1_Score_2.getText()); 
    daRun[0][2] = Double.parseDouble(jLabel_Run1_Score_3.getText()); 
    daRun[0][3] = Double.parseDouble(jLabel_Run1_Score_4.getText()); 
    daRun[0][4] = Double.parseDouble(jLabel_Run1_Score_5.getText()); 
    daRun[0][5] = Double.parseDouble(jLabel_Run1_Score_6.getText()); 
    daRun[0][6] = Double.parseDouble(jLabel_Run1_Score_7.getText()); 

    daRun[1][0] = Double.parseDouble(jLabel_Run2_Score_1.getText()); 
    daRun[1][1] = Double.parseDouble(jLabel_Run2_Score_2.getText()); 
    daRun[1][2] = Double.parseDouble(jLabel_Run2_Score_3.getText()); 
    daRun[1][3] = Double.parseDouble(jLabel_Run2_Score_4.getText()); 
    daRun[1][4] = Double.parseDouble(jLabel_Run2_Score_5.getText()); 
    daRun[1][5] = Double.parseDouble(jLabel_Run2_Score_6.getText()); 
    daRun[1][6] = Double.parseDouble(jLabel_Run2_Score_7.getText()); 

    for(int i = 0; i < 7; i++) 
    { 
     if(daRun[0][i] <= dMinScoreRun1) 
     { 
      dMinScoreRun1 = daRun[0][i]; 
     } 
     if(daRun[0][i] >= dMaxScoreRun1) 
     { 
      dMaxScoreRun1 = daRun[0][i]; 
     } 

     dTotalRun1 += daRun[0][i]; 
    } 

    dTotalRun1 = (dTotalRun1 - dMinScoreRun1 - dMaxScoreRun1)/dScoreUsed; 
    jLabel_TotalRun1.setText(String.valueOf(dTotalRun1)); 
    jLabel_Run1AddInfo.setText("Min Score: " + (dMinScoreRun1) + ", Max Score: " + (dMaxScoreRun1)); 

    for(int i = 0; i < 7; i++) 
    { 
     if(daRun[1][i] <= dMinScoreRun2) 
     { 
      dMinScoreRun2 = daRun[1][i]; 
     } 
     if(daRun[1][i] >= dMaxScoreRun2) 
     { 
      dMaxScoreRun2 = daRun[1][i]; 
     } 

     dTotalRun2 += daRun[1][i]; 
    } 

    dTotalRun2 = (dTotalRun2 - dMinScoreRun2 - dMaxScoreRun2)/dScoreUsed; 
    jLabel_TotalRun2.setText(String.valueOf(dTotalRun2)); 
    jLabel_Run2AddInfo.setText("Min Score: " + (dMinScoreRun2) + ", Max Score: " + (dMaxScoreRun2)); 

    if(dTotalRun1 >= dTotalRun2) 
     jLabel_FinalScore.setText(String.valueOf(dTotalRun1)); 
    else 
     jLabel_FinalScore.setText(String.valueOf(dTotalRun2)); 


    jPanel_Graph.repaint(); 
} 
}); 

JPanelの定義

JPanel jPanel_Graph = new JPanel(); 
jPanel_Graph.setBorder(new BevelBorder(BevelBorder.LOWERED, null, null, null, null)); 
jPanel_Graph.setBounds(729, 159, 700, 200); 
frame.getContentPane().add(jPanel_Graph); 

img = new BufferedImage(jPanel_Graph.getWidth(), 
         jPanel_Graph.getHeight(), 
         BufferedImage.TYPE_INT_RGB); 

g2dimg = (Graphics2D)img.getGraphics(); 

// Draw a filled white coloured rectangle on the entire area to clear it. 
g2dimg.setPaint(Color.WHITE); 
g2dimg.fill(new Rectangle2D.Double(0, 0, img.getWidth(), img.getHeight())); 

JPanelの描画イベント

class myJPanel extends JPanel 
{ 
private Rectangle2D.Double rectangle; 

public void paintComponent(Graphics g) 
{ 
    super.paintComponent(g); 

    for(int i = 0; i < 7; i++) 
    { 
     dHeight = daRun[0][i]; 

     rectangle = new Rectangle2D.Double(dX, dY, dWidth, dHeight); 
     g2dimg.setPaint(Color.red); 
     g2dimg.draw(rectangle); 
     g2dimg.fill(rectangle); 

     dX += dXIncrement; 
     g2dimg.drawImage(img, 0, 0, null); 
     } 
    } 
} 

（参考）

1. リストの選択イベント

   ありがとうございます！

Answer 1

私が知る限り、あなたの "グラフ"に何を描くべきかを知る方法はありません。基本的な考え方は、あなたの "グラフ"はデータ/モデルのペイントに焦点を当てるべきだから、データが変わったときにそれを伝える方法が必要です。

これを行う方法はたくさんあります。たとえば、データを追加/削除するモデルを考案し、グラフペインのリスナーが更新をトリガーして新しいデータで更新するなどの方法があります。

それとも、ただあなたが私はそれがすべてつなぎ合わせすべきか本当にわからないんだけど、それはこの場合は、可能性があるあなたに利用できる最も簡単な解決策

import java.awt.BorderLayout; 
import java.awt.Color; 
import java.awt.Dimension; 
import java.awt.EventQueue; 
import java.awt.Graphics; 
import java.awt.Graphics2D; 
import java.awt.geom.Rectangle2D; 
import javax.swing.DefaultListModel; 
import javax.swing.JFrame; 
import javax.swing.JList; 
import javax.swing.JPanel; 
import javax.swing.JScrollPane; 
import javax.swing.UIManager; 
import javax.swing.UnsupportedLookAndFeelException; 
import javax.swing.event.ListSelectionEvent; 
import javax.swing.event.ListSelectionListener; 

public class Test { 

    public static void main(String[] args) { 
     new Test(); 
    } 

    public Test() { 
     EventQueue.invokeLater(new Runnable() { 
      @Override 
      public void run() { 
       try { 
        UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName()); 
       } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) { 
        ex.printStackTrace(); 
       } 

       JFrame frame = new JFrame("Testing"); 
       frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
       frame.add(new TestPane()); 
       frame.pack(); 
       frame.setLocationRelativeTo(null); 
       frame.setVisible(true); 
      } 
     }); 
    } 

    public class TestPane extends JPanel { 

     private GraphPane graphPane; 

     public TestPane() { 
      setLayout(new BorderLayout()); 
      DefaultListModel<Double> listmodel = new DefaultListModel<>(); 
      for (int index = 0; index < 100; index++) { 
       listmodel.addElement(Math.random()); 
      } 

      graphPane = new GraphPane(); 
      add(graphPane); 

      JList<Double> listData = new JList<>(listmodel); 
      add(new JScrollPane(listData), BorderLayout.WEST); 

      listData.addListSelectionListener(new ListSelectionListener() { 
       @Override 
       public void valueChanged(ListSelectionEvent e) { 
        graphPane.setData(listData.getSelectedValuesList().toArray(new Double[0])); 
       } 
      }); 
     } 

    } 

    public class GraphPane extends JPanel { 

     private Double[] data; 

     public void setData(Double[] data) { 
      this.data = data; 
      repaint(); 
     } 

     @Override 
     public Dimension getPreferredSize() { 
      return new Dimension(200, 200); 
     } 

     @Override 
     protected void paintComponent(Graphics g) { 
      super.paintComponent(g); 
      if (data != null && data.length > 0) { 
       Graphics2D g2d = (Graphics2D) g.create(); 
       double barWidth = getWidth()/(double)data.length; 
       int xPos = 0; 
       for (Double value : data) { 
        double height = (getHeight() - 1) * value; 
        Rectangle2D bar = new Rectangle2D.Double(xPos, getHeight() - height, barWidth, height); 
        g2d.setColor(Color.GREEN); 
        g2d.fill(bar); 
        g2d.setColor(Color.BLACK); 
        g2d.draw(bar); 
        xPos += barWidth; 
       } 
       g2d.dispose(); 
      } 
     } 

    } 

}