Find a word in JTextArea and higlight it

[mehnihma]

I need to find a word in JTextArea and highlight it, can you help me with this code?

class managerClass implements ActionListener
   {
   
      @Override
      public void actionPerformed(ActionEvent e) {
      
      String myWord = txt.getText();
      Highlighter h = textArea.getHighlighter();
      
         if (e.getSource() == bFind)
         
         {
        	 
        	 
        	   
                pattern = Pattern.compile("\\b"+myWord+"\\b");
                
    

            Matcher matcher = pattern.matcher(myWord);

            while( matcher.find() )
                {
                int start = matcher.start();
                int end = matcher.end();

                try {
					h.addHighlight(start, end, DefaultHighlighter.DefaultPainter);
				} catch (BadLocationException e1) {
					
					e1.printStackTrace();
				}
                }
        	 
        	 
        	 
        	 
            
        	 
        	 JOptionPane.showMessageDialog(null,"No Match Found"); 
        	 
        	 
            }
      
      
      
      
      
      }

[mKorbel]

you have to search and use hightlighter from Document, linked tutorial contains searching and Hightlighter too

[mehnihma]

I have solved that, but how to set text color now? and why my if else wont work?

public void actionPerformed(ActionEvent e) {
         
            String myWord = txt.getText();
            Highlighter h = textArea.getHighlighter();
         
            if (e.getSource() == bFind)
            
            {
            
            
            
               pattern = Pattern.compile("\\b"+myWord+"\\b");
                
            
            
               Matcher matcher = pattern.matcher(myWord);
					
					boolean matchFound = matcher.matches(); // false
            
            
            
               if (!matchFound){
               
                  while( matcher.find() )
                  {
                     int start = matcher.start();
                     int end = matcher.end();
                  
                     try {
                        Font font = new Font("Verdana", Font.BOLD,40);
                     
                        h.addHighlight(start, end, DefaultHighlighter.DefaultPainter);
                     } 
                        catch (BadLocationException e1) {
                        
                           e1.printStackTrace();
                        }
                  }
               
               }
               
               else
               {
                  JOptionPane.showMessageDialog(null,"No Match Found"); 
               }
            
            
            
            
            
            
            
            
            
            
            }

[mKorbel]

you have to define own Highlighter.HighlightPainter or use DefaultHighlighter.DefaultPainter directly, and then to set Highlighter to JTextArea (called textPane here)

textPane.getHighlighter().addHighlight(int start, int end, yourPainter);

[mehnihma]

I will try that.
But why my if else is not working ? how to do this check?

[mehnihma]

and how to make yourPainter?
to apply font to it

[mKorbel]

not possible for JTexArea (without using Htlm), you have to use JComponents implementing styled text, maybe

[mehnihma]

I will try that

do you maybe know why is this not working now_ it finds only frist word but nothing else?

class managerClass implements ActionListener
      {
      
         @Override
         public void actionPerformed(ActionEvent e) {
         
            String myWord = txt.getText();
            Highlighter h = textArea.getHighlighter();
            String searchArea = textArea.getText();
         
            if (e.getSource() == bFind)
            
            {
            
            
               String[] searchArray = null;
               searchArray = searchArea.split("[^A-Z][^a-z][^0-9]");
            
               for(String element : searchArray)
               {
                  if(element.equals(myWord))
                  {
                     pattern = Pattern.compile("\\b"+myWord+"\\b");
                  	
                  	
                  	
                     for (int i = 0; i < searchArray.length; i++) 
                     
                     {

                     
                        Matcher matcher = pattern.matcher(searchArray[i]);
                     
                     
                        while( matcher.find() )
                        
                        
                        {
                           int start = matcher.start();
                           int end = matcher.end();
                        
                           try {
                           
                           
                              Highlighter hilit = new DefaultHighlighter();
                           
                           
                              Highlighter.HighlightPainter painter = new DefaultHighlighter.DefaultHighlightPainter(Color.YELLOW);
                           
                           //h.addHighlight(start, end, DefaultHighlighter.DefaultPainter);
                              h.addHighlight(start, end, painter);
                           
                           } 
                              catch (BadLocationException e1) {
                              
                                 e1.printStackTrace();
                              }
                        }
                     
                     
                     }
                  
                  
                  
                  
                  }
                  else
                  {
                     JOptionPane.showMessageDialog(null, "No match found", "Message", JOptionPane.INFORMATION_MESSAGE);
                  }
               }
            }

[mehnihma]

not possible for JTexArea (without using Htlm), you have to use JComponents implementing styled text, maybe

i did it like this

Highlighter.HighlightPainter painter = new DefaultHighlighter.DefaultHighlightPainter(Color.YELLOW);
                           
                           
                              h.addHighlight(start, end, painter);
                           	
                              textArea.setSelectionStart(start);
                              textArea.setSelectionEnd(end);
                              textArea.setSelectedTextColor(Color.PINK);

[mehnihma]

but why it highlights every word but colors just second one?

[mKorbel]

remove textArea.setSelectedTextColor(Color.PINK);

[mehnihma]

It does not work, and I need to change color of the selected text

[mKorbel]

this isn't simple possible override Caret and by using Highlighter together, there are bunch of code lines and required some knowledges about JTextComponents, I'm out of this thread

[peter_budo]

I was able to modify/use this example from Swing - A Beginner's Guide in the past to get it working with text area

import javax.swing.*;
import javax.swing.event.CaretEvent;
import javax.swing.event.CaretListener;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class CaretDemo {
    JLabel labelAll;
    JLabel labelSelected;
    
    JTextField textField;
    
    JButton buttonCut;
    JButton buttonPaste;
    final String allText = "All text: ";
    final String selectedText = "Selected text: ";
    
    public CaretDemo(){
        JFrame frame = new JFrame("Caret Demo");
        frame.getContentPane().setLayout(new FlowLayout());
        frame.setSize(200, 150);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        labelAll = new JLabel(allText);
        labelSelected = new JLabel(selectedText);
        
        textField = new JTextField("This is a test", 15);
        
        textField.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent actionEvent) {
                labelAll.setText((allText + textField.getText()));
                labelSelected.setText(selectedText + textField.getSelectedText());
            }
        });
        
        buttonCut = new JButton("Cut");
        buttonPaste = new JButton("Paste");
        
        buttonCut.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent actionEvent) {
                textField.cut();
                labelAll.setText(allText + textField.getText());
                labelSelected.setText(selectedText + textField.getSelectedText());
            }
        });

        buttonPaste.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent actionEvent) {
                textField.paste();
            }
        });

        textField.addCaretListener(new CaretListener() {
            public void caretUpdate(CaretEvent caretEvent) {
                labelAll.setText(allText + textField.getText());
                labelSelected.setText(selectedText + textField.getSelectedText());
            }
        });

        frame.getContentPane().add(textField);
        frame.getContentPane().add(buttonCut);
        frame.getContentPane().add(buttonPaste);
        frame.getContentPane().add(labelAll);
        frame.getContentPane().add(labelSelected);
        
        textField.setCaretPosition(5);
        textField.moveCaretPosition(7);
        
        frame.setVisible(true);
    }
    
    public  static void main(String[] args){
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                new CaretDemo();
            }
        });
    }
}