how to define action listener for buttons in java

Question

I have a jframe that includes JButton.I have six buttons in this frame, but I don\'t know how to define action listener for this buttons.please help to solve this probl

Answer 1

First you have to import the package java.awt.event.* to enable events. After the class name you have to add implements ActionListener so that the class can handle events. When you have created the buttons you have to add an actionlistener to each button. Since you haven't showed which code you use I make an example with a simple program that counts votes, if the user clicks the yesButton the votes are increased with 1 and if the user clicks the noButton the votes are decreased with 1.

Here is the code to add an ActionListener to each button:

yesButton.addActionListener(this);
noButton.addActionListener(this);

Then write the following code to handle the events:

public void actionPerformed(ActionEvent e) {
  JButton src = (JButton) e.getSource();
  if(src.getActionCommand().equals("Yes")) {
    yesCount++;
  } else {
    noCount++;
  }
  label.setText("Difference: " + (yesCount - noCount));
}

If you have 6 buttons you need to have an if statement and then 5 "else if" statements instead of only an if and an else statement.