Thread supposed to block keyevents

**Fecoooo** · 03-11-2012, 08:37 AM

Hi There!

I wrote 2 class, the first is a canvas wich can listen to keyevents, the second is a thread wich sets a boolean variable to true, than 2 secs later to false. While the variable is true, one shouldnt supposed to change anything with a keypress, but one can. How can this be possible? Thanks.

The listeners code.

Java Code:

@Override  
    public void keyPressed(KeyEvent e) {  
        if(!keyPressed){  
            KeyboardBlocker kBB = new KeyboardBlocker(keyPressed);  
            kBB.start();  
            switch(e.getKeyCode()){  
                case KeyEvent.VK_UP:  
                    rotUpperClockwise(upperRow, CLOCKWISE, 'Z');  
                    break;  
                case KeyEvent.VK_DOWN:  
                    rotUpperClockwise(upperRow, COUNTERCLOCKWISE, 'Z');      
                    break;  
                case KeyEvent.VK_LEFT:  
                    break;  
                case KeyEvent.VK_RIGHT:  
                    break;  
            }  
        }  
    }

the threads code:

Java Code:

package szakdoga_real;  
  
import java.util.logging.Level;  
import java.util.logging.Logger;  
  
public class KeyboardBlocker extends Thread{  
  
    private Boolean isKeyPressed;  
  
    public KeyboardBlocker(Boolean isKeyPressed) {  
        this.isKeyPressed = isKeyPressed;  
    }  
      
    @Override  
    public void run() {  
        isKeyPressed = true;  
        System.out.println(isKeyPressed);  
        try {  
            Thread.sleep(2000);  
        } catch (InterruptedException ex) {  
            Logger.getLogger(KeyboardBlocker.class.getName()).log(Level.SEVERE, null, ex);  
        }  
        isKeyPressed = false;  
        System.out.println(isKeyPressed);  
    }  
      
}

**Norm** · 03-11-2012, 01:20 PM

While the variable is true,

Where is the variable's value changed?
Can you explain what happens when you execute the code? Add some printlns that show where the code is executing and what the values of the variables are as it executes.

**DarrylBurke** · 03-11-2012, 01:55 PM

To get better help sooner, post a SSCCE (Short, Self Contained, Compilable and Executable) example that demonstrates the problem. The code snippets in isolation mean nothing.

For example, how is keyPressed in one class related to isKeyPressed in the other?

db

**Fecoooo** · 03-11-2012, 02:33 PM

It is supposed to start a new thread, wich changes a boolean value to true (i gave the varieble trough the constructor), wait 2 sec than change it back to false (its in run method). It changes the value (i printed the values out) but still i can press button and reach the switch statement. I resolved the problem tohugt

Java Code:

if (System.currentTimeMillis() - lastKeyPress < 2000)  
  return;  
lastKeyPress = System.currentTimeMillis();

Thank you anyways

**Norm** · 03-11-2012, 02:37 PM

Can you make a SSCCE that shows the problem?
Without a fully functional program that shows all of what is happening, how can this problem be solved? There are too many ways to do it wrong.