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javaswingjtextfieldpromptwindowbuilder

How to set Text like Placeholder in JTextfield in swing


I want to put some texts in text-Field when the form is load which instruct to user and when user click on that text-filed the texts remove automatically.

 txtEmailId = new JTextField();
 txtEmailId.setText("Email ID");

i have wrote above code but it display the text and keep as it is when user click on that text button i want to remove it.

is there any way to do this task?


Solution

  • I use to override the text fields paint method, until I ended up with more custom text fields then I really wanted...

    Then I found this prompt API which is simple to use and doesn't require you to extend any components. It also has a nice "buddy" API

    This has now been included in the SwingLabs, SwingX library which makes it even eaiser to use...

    For example (this uses SwingX-1.6.4)

    PromptSupport

    import java.awt.BorderLayout;
    import java.awt.EventQueue;
    import java.awt.Font;
    import java.awt.GridBagConstraints;
    import java.awt.GridBagLayout;
    import javax.swing.JFrame;
    import javax.swing.JTextField;
    import javax.swing.UIManager;
    import javax.swing.UnsupportedLookAndFeelException;
    import org.jdesktop.swingx.prompt.PromptSupport;
    
    public class PromptExample {
    
        public static void main(String[] args) {
            new PromptExample();
        }
    
        public PromptExample() {
            EventQueue.invokeLater(new Runnable() {
                @Override
                public void run() {
                    try {
                        UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
                    } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
                    }
    
                    JTextField bunnies = new JTextField(10);
                    JTextField ponnies = new JTextField(10);
                    JTextField unicorns = new JTextField(10);
                    JTextField fairies = new JTextField(10);
    
                    PromptSupport.setPrompt("Bunnies", bunnies);
                    PromptSupport.setPrompt("Ponnies", ponnies);
                    PromptSupport.setPrompt("Unicorns", unicorns);
                    PromptSupport.setPrompt("Fairies", fairies);
    
                    PromptSupport.setFocusBehavior(PromptSupport.FocusBehavior.HIDE_PROMPT, bunnies);
                    PromptSupport.setFocusBehavior(PromptSupport.FocusBehavior.HIGHLIGHT_PROMPT, ponnies);
                    PromptSupport.setFocusBehavior(PromptSupport.FocusBehavior.SHOW_PROMPT, unicorns);
    
                    PromptSupport.setFontStyle(Font.BOLD, bunnies);
                    PromptSupport.setFontStyle(Font.ITALIC, ponnies);
                    PromptSupport.setFontStyle(Font.ITALIC | Font.BOLD, unicorns);
    
                    JFrame frame = new JFrame("Testing");
                    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                    frame.setLayout(new GridBagLayout());
                    GridBagConstraints gbc = new GridBagConstraints();
                    gbc.gridwidth = GridBagConstraints.REMAINDER;
                    frame.add(bunnies, gbc);
                    frame.add(ponnies, gbc);
                    frame.add(unicorns, gbc);
                    frame.add(fairies, gbc);
                    frame.pack();
                    frame.setLocationRelativeTo(null);
                    frame.setVisible(true);
                }
            });
        }
    
    }