Member Avatar for Blackeagle

Hello,

i have two questions concerning programming in Java.

1st Q:
i have more than frame opened for the same program and when i want to close one of them, all the program closes as well.
basically i write this code for closing the frame when clicking on a button:

JButton exit= new JButton("Exit");
exit.addActionListener( new ActionListener()
		 {
		   public void actionPerformed(ActionEvent e) 
		   {
			System.exit(0);
		   }
		 });

2nd Q:
Why do the above addActionKistener method only deals with final variables ??


Thank you in advance

  • 3 Contributors
  • 4 Replies
  • 211 Views
  • 1 Day Discussion Span
  • Latest Post Latest Post by Blackeagle

Recommended Answers

All 4 Replies

Member Avatar for darkagn

Q1:

The System.exit() method terminates the Java Virtual Machine, not just a single frame.

Q2:

Not sure what you mean by this Question.

Member Avatar for Blackeagle

Is there a way to close one frame only?

about Q2.
lets say i have a variable like this:
public int temp=1;

and then in one of the methods i use this code:

x.addActionListener( new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
temp+=5;
}
});


i'll get an error saying that temp should be final.

any reason why that happens ?

Member Avatar for stephen84s

Is there a way to close one frame only?

Check out the dispose() method of the JFrame class.
You can also check this tutorial to learn more about Event Handling in Java.

The second question you mentioned is related to the concept of anonymous inner classes, but if you are beginning in Java then I suggest for now you stick to the method mentioned in The Java Tutorial which is my first link.

And please use [code] tags to post your code. Look here and here for more information of code tags

commented: Well explained :) +3
Member Avatar for Blackeagle

i'll try that and Thank you all ..

sorry for not using codes in my post .. i'm still new to this forum.

Be a part of the DaniWeb community

We're a friendly, industry-focused community of developers, IT pros, digital marketers, and technology enthusiasts meeting, networking, learning, and sharing knowledge.