Jtext highlight visited line s

[Anu Bhagat]

I can highlight visited lines in one color. I want to highlight previously visited lines with gray and the current line with yellow.
My code is as follows. With this all visted lines are highlighted with yellow. When step button is clicked the actionPerformed method is invoked.

Please help Thanks in advance.

Anu

public class stepper {
private javax.swing.JButton stepButton;
private Highlighter.HighlightPainter graypainter;
private Highlighter.HighlightPainter yellowpainter;
int numLines = 0;
int lineNumber = 0;
int startIndex = 0;
int endIndex = 0;
private void stepButtonActionPerformed(java.awt.event.ActionEvent evt) {
try {
hasDiagramChanged = true;
int executedStartIndex = 0;
int executedEndIndex = 0;
if (lineNumber <= numLines) {
startIndex = jTextArea1.getLineStartOffset(lineNumber);
endIndex = jTextArea1.getLineEndOffset(lineNumber);
//System.out.println(" startIndex = " + startIndex + " endIndex= " + endIndex);
jTextArea1.setCaretPosition(endIndex);
//graypainter = new DefaultHighlighter.DefaultHighlightPainter(Color.GRAY);
yellowpainter = new DefaultHighlighter.DefaultHighlightPainter(Color.YELLOW);
jTextArea1.getHighlighter().addHighlight(startIndex, endIndex, yellowpainter);
lineNumber++;
//System.out.println(" lineNumber " + lineNumber);
} else {
System.out.println("end of the file");
//jTextArea1.setCaretPosition(jTextArea1.getText().length() -1);
}
//Now use gray painter for previously visited lines except for the current line. THIS DOES NOT WORK. I NEED HELP WITH THIS.
executedStartIndex = jTextArea1.getLineStartOffset(0);
executedEndIndex = jTextArea1.getLineEndOffset(lineNumber-1);
graypainter = new DefaultHighlighter.DefaultHighlightPainter(Color.GRAY);
jTextArea1.getHighlighter().addHighlight(executedStartIndex, executedEndIndex, graypainter);
} catch (BadLocationException ex) {
System.out.println("We got exception in stepButtonActionPerformed");
Logger.getLogger(SequenceStepper.class.getName()).log(Level.SEVERE, null, ex);
}
}
} 

[Anu Bhagat]

Please give any pointer hint that will help me to hilight the current line with different color than all the previously visited lines.

Thanks in advance Here is my java class

Anu

/**
*
* @author bhagata
*/
public class StepExer extends javax.swing.JFrame {
/** Creates new form StepExer */
public StepExer() {
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")
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents() {
loadButton = new javax.swing.JButton();
stepButton = new javax.swing.JButton();
jScrollPane1 = new javax.swing.JScrollPane();
jTextArea1 = new javax.swing.JTextArea();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
loadButton.setText("Load");
loadButton.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
loadButtonActionPerformed(evt);
}
});
stepButton.setText("Step");
stepButton.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
stepButtonActionPerformed(evt);
}
});
jTextArea1.setColumns(20);
jTextArea1.setRows(5);
jScrollPane1.setViewportView(jTextArea1);
javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGap(50, 50, 50)
.addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, 335, javax.swing.GroupLayout.PREFERRED_SIZE)
.addContainerGap(80, Short.MAX_VALUE))
.addGroup(layout.createSequentialGroup()
.addGap(78, 78, 78)
.addComponent(loadButton)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 130, Short.MAX_VALUE)
.addComponent(stepButton)
.addGap(147, 147, 147))
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGap(23, 23, 23)
.addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, 149, javax.swing.GroupLayout.PREFERRED_SIZE)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 50, Short.MAX_VALUE)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(loadButton)
.addComponent(stepButton))
.addGap(21, 21, 21))
);
pack();
}// </editor-fold>
private void loadButtonActionPerformed(java.awt.event.ActionEvent evt) {
JFileChooser fileChooser = new JFileChooser();
fileChooser.setCurrentDirectory( new File( "./output/cmd") );
fileChooser.addChoosableFileFilter(new TextFilter());
int caretPosition = 0; //at the start the file
//typeString = null;
int actionDialog = fileChooser.showOpenDialog(this);
if (actionDialog == JFileChooser.APPROVE_OPTION) {
File selectedFile = fileChooser.getSelectedFile();
try{
BufferedReader input = new BufferedReader(new FileReader(selectedFile));
String line;
//load the contents of the selected file in jTextArea1
while (( line = input.readLine()) != null){
jTextArea1.append(line + "\n");
numLines++;
}
//System.out.println("number of lines in the laoded file = " + numLines);
input.close();
jTextArea1.setCaretPosition(caretPosition);
}catch(FileNotFoundException fnfe){
System.out.println("An error has occurred" + fnfe);
}catch(IOException ioe) {
System.out.println("An error has occurred" + ioe);
}
}
}
private void stepButtonActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
try {
// TODO add your handling code here:
hasDiagramChanged = true;
int executedStartIndex = 0;
int executedEndIndex = 0;
//System.out.print(" numLines = " + numLines + " lineNumber " + lineNumber);
if (lineNumber <= numLines) {
startIndex = jTextArea1.getLineStartOffset(lineNumber);
endIndex = jTextArea1.getLineEndOffset(lineNumber);
//System.out.println(" startIndex = " + startIndex + " endIndex= " + endIndex);
jTextArea1.setCaretPosition(endIndex);
//PAINT CURRENTLY VISITED LINE WITH YELLOW- WORKS
yellowpainter = new DefaultHighlighter.DefaultHighlightPainter(Color.YELLOW);
jTextArea1.getHighlighter().addHighlight(startIndex, endIndex, yellowpainter);
lineNumber++;
//System.out.println(" lineNumber " + lineNumber);
} else {
System.out.println("end of the file");
//jTextArea1.setCaretPosition(jTextArea1.getText().length() -1);
}
//for (int i = 0; i < lineNumber; i++) {//WANT TO PAINT GRAY HERE- DOES NOT WORK- PREVIOUSLY VISITED LINE REMIAN GRAY
executedStartIndex = jTextArea1.getLineStartOffset(0);; //jTextArea1.getLineStartOffset(i);
System.out.println("lineNumber= " + lineNumber );
executedEndIndex = jTextArea1.getLineEndOffset(lineNumber-1);
System.out.println(" (lineNumber-1) = " + (lineNumber-1) +
" executedStartIndex = " + executedStartIndex +
" executedEndIndex = " + executedEndIndex );
graypainter = new DefaultHighlighter.DefaultHighlightPainter(Color.GRAY);
jTextArea1.getHighlighter().addHighlight(executedStartIndex, executedEndIndex, graypainter);
//System.out.println(" DID WE GET HERE MUST HAVE PAINTED GRAY ");
//}
} catch (BadLocationException ex) {
System.out.println("We got exception in stepButtonActionPerformed");
Logger.getLogger(StepExer.class.getName()).log(Level.SEVERE, null, ex);
}
}
//Class to create a filer for filechooser //change the filer to .cmd files
class TextFilter extends javax.swing.filechooser.FileFilter {
public boolean accept(File file) {
String filename = file.getName();
//return filename.endsWith(".txt");
return filename.endsWith(".cmd");
}
public String getDescription() {
//return "*.txt";
return "*.cmd";
}
}
/**
* @param args the command line arguments
*/
public static void main(String args[]) {
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
new StepExer().setVisible(true);
}
});
}
// Variables declaration - do not modify
private javax.swing.JScrollPane jScrollPane1;
private javax.swing.JTextArea jTextArea1;
private javax.swing.JButton loadButton;
private javax.swing.JButton stepButton;
// End of variables declaration
private Highlighter.HighlightPainter graypainter;
private Highlighter.HighlightPainter yellowpainter;
int numLines = 0;
int lineNumber = 0;
int startIndex = 0;
int endIndex = 0;
boolean hasDiagramChanged = false;
}