Question

i try to move it to the right(x++) every seconds

i try to move it with thread..

1. how to do it? (and can see it move every second)
2. there are another way to do it without use thread?
3. what layout manager that i should use?

heres i try..

public class help {
    JFrame frame = new JFrame();
    JLabel label = new JLabel("target");

    public help() {
        frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
        frame.setSize(800,600);
        frame.setLayout(new GridLayout());
        frame.add(label);
        label.setPreferredSize(new Dimension(100,100));
        label.setLocation(400, 300);

        frame.getContentPane().validate();
        frame.repaint();
        frame.setVisible(true);

        mysterious();
    }

    void mysterious(){
     ////////////////////////////////
     // part of edit responding David kroukamp  
    Thread t = new Thread(new Runnable() {
    @Override
    public void run() {
         try{

            for (int z=0; z<10; z++){
            label.setLocation((label.getLocationOnScreen().x+10), label.getLocationOnScreen().y);
            Thread.sleep(1000);  
            } 
        }catch(Exception ae){

    }
    }
});
t.start();
    //////////////////////////////



    }
    public static void main(String[]args){
        new help();  
        }
}

thanks a lot for any kind of help

Answer 1

• Class names begin with capital letters i.e Help
• Swing components should be created and modified on Event Dispatch Thread

• A new Thread is created like this:

  Thread t = new Thread(new Runnable() {
      @Override
      public void run() {
          //work here
      }
  });
  t.start();//start thread
  

however I’d suggest a Swing Timer as it runs on EDT:

• How to Use Swing Timers

EDIT:

As per your questions I suggest using a Timer the creating thread point was for general knowledge.

The probelm is the Thread is not run on EDT Thread of your swing GUI where as a Timer does:

 int delay = 1000; //milliseconds
  ActionListener taskPerformer = new ActionListener() {
      int count=0;
      public void actionPerformed(ActionEvent evt) {
           if(count==10) {//we did the task 10 times
                 ((Timer)evt.getSource()).stop();
            }

            label.setLocation((label.getLocationOnScreen().x+10), label.getLocationOnScreen().y);
            System.out.println(SwingUtilities.isEventDispatchThread());
           count++;
      }
  };
  new Timer(delay, taskPerformer).start();

Reference:

• http://docs.oracle.com/javase/7/docs/api/javax/swing/Timer.html