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POhow to drawline with button event?
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  1. POhow to drawline with button event?
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    copied!<p>MY program here is basically a JPanel with three buttons I want to use one of the buttons to drawLine on the JPanel. I have two classes one that extends JPanel (Panel.class) and the other that extends the JFrame (frame.class)</p> <p>The button is in the frame.class which calls a method in panel.class called drawer(); to which the button event passes xy co-ordinates and then drawer passes those co-ordinates to four int var in panel.class and invoke repaint(); but no line in drawn. </p> <p>Panel.class code :</p> <pre><code>package my.jpanel; import java.awt.*; import java.awt.event.*; import java.io.IOException; import java.util.ArrayList; import javax.swing.*; public class Panel extends javax.swing.JPanel { //draws using the initial (x1, y1) co-ordiantes of the previous i in the array private int x1, y1, x2, y2; ArrayList linex1 = new ArrayList(); ArrayList linex2 = new ArrayList(); ArrayList liney1 = new ArrayList(); ArrayList liney2 = new ArrayList(); public int fx1, fy1, fx2, fy2; public void drawer(int fx1i, int fy1i, int fx2i, int fy2i){ fx1 = fx1i; fy1 = fy1i; fx2 = fx2i; fy2 = fy2i; repaint(); } public Panel() { addMouseListener( new MouseAdapter(){ public void mousePressed (MouseEvent e){ x1 = e.getX(); y1 = e.getY(); int z = linex1.size(); System.out.println("z: "+z); if (z!=0){ linex1.add(linex2.get(z-1)); liney1.add(liney2.get(z-1));} else{ linex1.add(x1); liney1.add(y1); System.out.println("x1:"+x1);} } public void mouseReleased( MouseEvent e){ x2 = e.getX(); y2 = e.getY(); linex2.add(x2); liney2.add(y2); System.out.println("x1:"+x1+" x2:"+x2+" y1: "+y1+" y2: "+y2); double slope = ((((double)y2)-((double)y1))/(((double)x2)-((double)x1))); System.out.println("Slope of line: "+slope); repaint(); } }); addMouseMotionListener ( new MouseMotionAdapter(){ public void mouseDragged(MouseEvent e){ x2 = e.getX(); y2 = e.getY(); repaint(); } }); } public Dimension getPreferredSize(){ return new Dimension(250, 150); } public void paintComponent( Graphics g ){ super.paintComponent(g); // g.drawOval(Math.min(x1, x2), Math.min(y1, y2), Math.abs(x1-x2), Math.abs(y1-y2)); g.drawLine(fx1, fy1, fx2, fy2); g.drawLine(x1, y1, x2, y2); int lx1 = linex1.size(); int lx2 = linex2.size(); int ly1 = liney1.size(); int ly2 = liney2.size(); System.out.println("lx1: "+lx1); System.out.println("lx2: "+lx2); System.out.println("ly1: "+ly1); System.out.println("ly2: "+ly2); System.out.println("-------------"); if ((lx1 != 0 &amp;&amp; lx2 != 0 &amp;&amp; ly1 != 0 &amp;&amp; ly2 != 0) &amp;&amp; (lx1 != 1 &amp;&amp; ly1 != 1 &amp;&amp; !(lx2 &lt; (lx1)) &amp;&amp; !(ly2 &lt; (ly1)))){ for (int i=0; i&lt;lx1; ++i){ int x1x = ((int) (linex1.get(i))); int x2x = ((int) (linex2.get(i))); int y1y = ((int) (liney1.get(i))); int y2y = ((int) (liney2.get(i))); g.drawLine(x1x,y1y,x2x, y2y);} if ((lx1 != 0 &amp;&amp; lx2 != 0 &amp;&amp; ly1 != 0 &amp;&amp; ly2 != 0) &amp;&amp; (lx1 != 1 &amp;&amp; ly1 != 1 &amp;&amp; lx2&lt;lx1 &amp;&amp; ly2&lt;ly1)){ for (int x1=0, x2=0; x1&lt;linex1.size() &amp;&amp; x2&lt;linex2.size()-1; ++x1, ++x2){ int x1x = ((int) (linex1.get(x1))); int x2x = ((int) (linex2.get(x2))); int y1y = ((int) (liney1.get(y1))); int y2y = ((int) (liney2.get(y2))); g.drawLine(x1x,y1y,x2x, y2y);} } } } public void Panelint() { initComponents(); } @SuppressWarnings("unchecked") // &lt;editor-fold defaultstate="collapsed" desc="Generated Code"&gt; private void initComponents() { setBackground(new java.awt.Color(153, 204, 255)); javax.swing.GroupLayout layout = new javax.swing.GroupLayout(this); this.setLayout(layout); layout.setHorizontalGroup( layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGap(0, 400, Short.MAX_VALUE) ); layout.setVerticalGroup( layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGap(0, 300, Short.MAX_VALUE) ); }// &lt;/editor-fold&gt; // Variables declaration - do not modify // End of variables declaration </code></pre> <p>}</p> <p>frame.class code is below:</p> <pre><code>/* * To change this template, choose Tools | Templates * and open the template in the editor. */ package my.jpanel; import java.awt.Graphics; import java.io.BufferedWriter; import java.io.File; import java.io.FileWriter; import java.io.IOException; import java.text.SimpleDateFormat; import java.util.ArrayList; import java.util.Date; import java.util.Iterator; import java.util.Scanner; // } public class frame extends javax.swing.JFrame { ArrayList&lt;Integer&gt; drawnpattern = new ArrayList&lt;Integer&gt;(); ArrayList&lt;Integer&gt; filepattern = new ArrayList&lt;Integer&gt;(); public frame() { initComponents(); } /** * This method is called from within the constructor to initialize the form. * WARNING: Do NOT modify this code. The content of this method is always * regenerated by the Form Editor. */ @SuppressWarnings("unchecked") // &lt;editor-fold defaultstate="collapsed" desc="Generated Code"&gt; private void initComponents() { panel1 = new my.jpanel.Panel(); btn = new javax.swing.JButton(); jScrollPane1 = new javax.swing.JScrollPane(); jta = new javax.swing.JTextArea(); jButton1 = new javax.swing.JButton(); jButtondraw = new javax.swing.JButton(); setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE); panel1.setBackground(new java.awt.Color(153, 204, 255)); javax.swing.GroupLayout panel1Layout = new javax.swing.GroupLayout(panel1); panel1.setLayout(panel1Layout); panel1Layout.setHorizontalGroup( panel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGap(0, 250, Short.MAX_VALUE) ); panel1Layout.setVerticalGroup( panel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGap(0, 150, Short.MAX_VALUE) ); btn.setText("Print Co-ordinate and Save File"); btn.addActionListener(new java.awt.event.ActionListener() { public void actionPerformed(java.awt.event.ActionEvent evt) { btnActionPerformed(evt); } }); jta.setColumns(20); jta.setRows(5); jScrollPane1.setViewportView(jta); jButton1.setText("Match patterns"); jButton1.addActionListener(new java.awt.event.ActionListener() { public void actionPerformed(java.awt.event.ActionEvent evt) { jButton1ActionPerformed(evt); } }); jButtondraw.setText("Draw Both line"); javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane()); getContentPane().setLayout(layout); layout.setHorizontalGroup( layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addComponent(jScrollPane1) .addGroup(layout.createSequentialGroup() .addGap(18, 18, 18) .addComponent(btn) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 24, Short.MAX_VALUE) .addComponent(jButtondraw) .addGap(18, 18, 18) .addComponent(jButton1) .addGap(24, 24, 24)) .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup() .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE) .addComponent(panel1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE) .addGap(107, 107, 107)) ); layout.setVerticalGroup( layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGroup(layout.createSequentialGroup() .addContainerGap() .addComponent(panel1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 43, Short.MAX_VALUE) .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE) .addComponent(btn) .addComponent(jButton1) .addComponent(jButtondraw)) .addGap(18, 18, 18) .addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, 107, javax.swing.GroupLayout.PREFERRED_SIZE)) ); pack(); }// &lt;/editor-fold&gt; private void btnActionPerformed(java.awt.event.ActionEvent evt) { String axis = null; for (int i=0; i&lt;(panel1.linex1.size()); ++i ){ axis = ("Line "+i+": "+" x1: "+panel1.linex1.get(i)+" y1: "+panel1.liney1.get(i)+" x2: "+panel1.linex2.get(i)+" y2: "+panel1.liney2.get(i)+"."); jta.append(axis); jta.append("\n"); } try { File file = new File("I:/Programming/linedata.txt"); FileWriter fw = new FileWriter(file.getAbsoluteFile(),true); // append=true so that we don't overwrite the whole file BufferedWriter bw = new BufferedWriter(fw); // buffer writing for (int i=0; i&lt;(panel1.linex1.size()); ++i ){ bw.write("x1:"+panel1.linex1.get(i)); bw.write("y1:"+panel1.liney1.get(i)); bw.write("x2:"+panel1.linex2.get(i)); bw.write("y2:"+panel1.liney2.get(i)); } bw.flush(); bw.close(); } catch (IOException e) { e.printStackTrace(); } } private void jButtondrawActionPerformed(java.awt.event.ActionEvent evt){ //for (int i=0; i&lt;((filepattern.size())/4); i++){ filepattern.add(26); filepattern.add(50); filepattern.add(36); filepattern.add(130); filepattern.add(36); filepattern.add(130); filepattern.add(64); filepattern.add(97); filepattern.add(64); filepattern.add(97); filepattern.add(81); filepattern.add(127); filepattern.add(81); filepattern.add(127); filepattern.add(100); filepattern.add(96); filepattern.add(100); filepattern.add(96); filepattern.add(122); filepattern.add(128); filepattern.add(122); filepattern.add(128); filepattern.add(127); filepattern.add(57); int fx1 = filepattern.get(0); int fy1 = filepattern.get(1); int fx2 = filepattern.get(2); int fy2 = filepattern.get(3); panel1.drawer(fx1, fy1, fx2, fy2); } private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) { String axis = null; // add into array current drawn pattern for (int i=0; i&lt;(panel1.linex1.size()); ++i ){ drawnpattern.add((int)panel1.linex1.get(i)); drawnpattern.add((int)panel1.liney1.get(i)); drawnpattern.add((int)panel1.linex2.get(i)); drawnpattern.add((int)panel1.liney2.get(i)); // append current drawn pattern line data axis = ("Line "+i+": "+" x1: "+panel1.linex1.get(i)+" y1: "+panel1.liney1.get(i)+" x2: "+panel1.linex2.get(i)+" y2: "+panel1.liney2.get(i)+"."); jta.append(axis); jta.append("\n"); // read file and append file data to filepattern array filepattern.add(26); filepattern.add(50); filepattern.add(36); filepattern.add(130); filepattern.add(36); filepattern.add(130); filepattern.add(64); filepattern.add(97); filepattern.add(64); filepattern.add(97); filepattern.add(81); filepattern.add(127); filepattern.add(81); filepattern.add(127); filepattern.add(100); filepattern.add(96); filepattern.add(100); filepattern.add(96); filepattern.add(122); filepattern.add(128); filepattern.add(122); filepattern.add(128); filepattern.add(127); filepattern.add(57); // after adding original data then we need to calculate the values of original data and also the incoming data. // then we need to use our formula to compare } } /** * @param args the command line arguments */ public static void main(String args[]) { /* Set the Nimbus look and feel */ //&lt;editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) "&gt; /* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel. * For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html */ try { for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) { if ("Nimbus".equals(info.getName())) { javax.swing.UIManager.setLookAndFeel(info.getClassName()); break; } } } catch (ClassNotFoundException ex) { java.util.logging.Logger.getLogger(frame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex); } catch (InstantiationException ex) { java.util.logging.Logger.getLogger(frame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex); } catch (IllegalAccessException ex) { java.util.logging.Logger.getLogger(frame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex); } catch (javax.swing.UnsupportedLookAndFeelException ex) { java.util.logging.Logger.getLogger(frame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex); } //&lt;/editor-fold&gt; /* Create and display the form */ java.awt.EventQueue.invokeLater(new Runnable() { public void run() { new frame().setVisible(true); } }); } // Variables declaration - do not modify private javax.swing.JButton btn; private javax.swing.JButton jButton1; private javax.swing.JButton jButtondraw; private javax.swing.JScrollPane jScrollPane1; private javax.swing.JTextArea jta; private my.jpanel.Panel panel1; // End of variables declaration } </code></pre>
 

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