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Clear TextField on button press - Java Applet

I have a Java Applet for login form. It has 2 TextFields, username and password. I need to clear them on clicking Reset button. This is the code I have written.
public class LoginForm extends Applet implements ActionListener
{
TextField name, pass, hidden;
Button b1, b2;
public void init()
{
name = new TextField(20);
pass = new TextField(20);
b2 = new Button("Reset");
add(name);
add(pass);
add(b2);
b2.addActionListener(this);
}
public void paint(Graphics g)
{
g.drawString("Hello", 10, 150);
}
public void actionPerformed(ActionEvent e) {
System.out.println(e);
name.setText("");
pass.setText("");
repaint();
}
}
But this is not working properly.
Once I click the Reset button, the actionPerformed() method gets called and it also calls repaint(). (I can see "Hello" being displayed).
But the TextFields do not get cleared.
If I make following changes in actionPerformed
name.setText(" "); // please note the spaces
pass.setText(" ");
then it works. But I don't want spaces there. I want the TextFields to get blank.
Any help is appreciated.

Probably it is not good solution, but this is a workaround.Before setting the text invoke getText method and it will reset. Pretty strange! This behaviour is marked as Bug on this page
public void actionPerformed(ActionEvent e) {
System.out.println(e);
name.getText();
pass.getText();
name.setText("");
pass.setText("");
repaint();
revalidate();
}
Another solution would be setting text with space. But not if you have password-like fields which have setEchoChar('*').
public void actionPerformed(ActionEvent e) {
System.out.println(e);
name.setText(" ");
pass.setText(" ");
repaint();
revalidate();
}

just put blank in text fields.
public void actionPerformed(ActionEvent e) {
name.getText();
pass.getText();
name.setText("");
pass.setText("");
repaint();
revalidate();
}

Add two buttons if another button has been pressed

b.button1 = new JButton("Deal");
b.button1.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
//code
b.button2 = new JButton("Hit");
panel.add(b.button2);
panel.validate();
b.button2.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
//code
}
});
b.button3 = new JButton("Stay");
panel.add(b.button3);
panel.validate();
b.button3.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
//code
}
}
});
So I want The Buttons Hit and Stay to be added as soon as the Deal button has been pressed. I searched for a solution and found the panel.validate() method. I used it but now if I press the Deal button it only adds the Hit button.

You could add the buttons before and make them "hidden". If you press the button, you can "show" them to include them.

Not able to call an action listener for a radio button

I am writing a code where there is a tabbedpane containing 4 tabs. Each tab is containing some radio buttons and a button. the button should act according the pressed radio button. Following is my code for it.
if(radiobtn1.isSelected()==true)
` {
System.out.println("option 1 selected");
radiobtn1.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
Button1.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
// action for radio button 1
}
});
}
});
}
else if(radiobtn2.isSelected()==true){
System.out.println("option 2 selected");
radiobtn2.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
Button1.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
// action for radio button 2
}
});
}
});
}
}
But whenever I am pressing a radio button its action listener is not getting called. Is there anything wrong in my code?

Modify your code as below
rdbtnSample.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent arg0) {
if (rdbtnSample.isSelected())
System.out.println("Button Pressed");
else
System.out.println("Button Released");
}
});
add the if condition inside the action performed.
By default radio button will be deselected.

I think you should use the data or the switch parameters to control the action content. Not by the dynamic control the action listener in the buttons.
Just like use the
int radioButtonIndexPressed = 0;
and in the button press action , use the radioButtonIndexPressed to decide the real action.

Handling exit button which is create automatically?

I am building a text editor and I don't know how to handle a listener on Swing exit button, which is create automatically.
I want to use dialogs when user doesn't save file, for example press exit button.

final JFrame f = new JFrame("Good Location & Size");
// make sure the exit operation is correct.
f.setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE);
f.addWindowListener( new WindowAdapter() {
public void windowClosing(WindowEvent we) {
// pop the dialog here, and if the user agrees..
System.exit(0);
}
});
As seen in this answer to Best practice for setting JFrame locations, which serializes the frame location & size before exiting.

Assuming you have a handle on your window, assuming it's a Window object (e.g. a JFrame or other kind of window), you can listen to WindowEvent events. Here is an example with windowClosed, you can replace it with windowClosing if you need to intercept it before.
frame.addWindowListener(new WindowAdapter() {
#Override
public void windowClosed(WindowEvent e) {
// do something here
}
});

Go stepwise:
Declare a boolean variable saved and set its default value to false.
When user saves the file, change it to true
When exit button is pressed, check the variable.
If true, exit, else, prompt user for saving file.
So, finally this code snippet looks like:
public boolean saved = false;
saveButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
saved = true;
//Code to save file
}
});
exitButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
if(saved)
System.exit(0);
else {
//Code to prompt user to save file
}
}
});

How to delete text when a user clicks a JTextField?

In my program, the user writes something in a JTextField then clicks a 'generate' button, which triggers the characters in the JTextField to be drawn to a JPanel.
I would then like to clear all the text in the JTextField when the user clicks the JTextField again. I tried to achieve this by adding a FocusListener and an ActionListener to the JTextField, however my attempts did not work. Moreover, my implementation of the FocusListener gave an Unreachable Statement compiler error.
Is this possible to do in Java and if so how can I do this?
The code below is my ActionListener implementation.
dfaText = new JTextField(6);
dfaText.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
generateLabel.setText("NOOOOO!!!");
dfaText.setText("");
isDfaDrawn = false;
canDraw = false;
repaint();
}
});

Add a mouse listener:
field.addMouseListener(new MouseAdapter() {
#Override
public void mouseClicked(MouseEvent e) {
field.setText("");
}
});
Bear in mind this could get frustrating if the user legitimately clicks elsewhere and returns to the field. You may wish to maintain some state, e.g. only clear the field if the button has been clicked in the interim.

You can do this:
textField.addMouseListener(new MouseAdapter() {
#Override
public void mouseClicked(MouseEvent e) {
textField.setText("");
}
});

Just an addition to others' code.
public void textfieldMouseClicked(java.awt.event.MouseEvent evt) {
uname_tf.setText(null);
} //This will set the JTextfield blank on mouse click//
public void textfieldFocusLost(java.awt.event.FocusEvent evt) {
uname_tf.setText("Username");
} //This will bring back the default text when not in focus//
Hope it helps, Cheers!!!

If you want it just one Click on it to delete the text you can do like this :
textField.addMouseListener(new java.awt.event.MouseAdapter() {
public void mousePressed(java.awt.event.MouseEvent evt) {
textFieldMousePressed(evt);
}
});
private void textFieldMousePressed(java.awt.event.MouseEvent evt) {
textField.setText("");
}

Add 1 line to you buttonMethod e.g:
txtfield.clear();
or set your txtfield to an empty string