Measure or detect how long a button was help down

[esy928]

hello!
is there a method or class that lets you assign events to the keys of your keyboard (spacebar to fire gun)? and is there a way to measure how long the key was held down? thanks!!! any help is greatly appreciated.. ive tried google-ing it but i had no luck in looking for a class/method that does those things =) tnx

[jasimp]

KeyListener
Using keyListener
You need to implement it, and then add a listener with addKeyListener(this) and you need to use all of the methods provided because it is a interface (they are listed in the link I gave you.) The second link should help you learn how to use it. Using Google you could find the key codes for each of the keys on the keyboard.

[esy928]

hmm.. ive tried using them but can they measure how long you held a button down?

[jasimp]

I'm not sure how to do that. Timing how long between a keyPressed and a keyReleased might work. Maybe someone else will know.

[Alex Edwards]

Why not store the current time in a data type (like a long) when the key is pressed and when the key is released subtract the new time from the old time?

[Alex Edwards]

Why not store the current time in a data type (like a long) when the key is pressed and when the key is released subtract the new time from the old time?

Here's an example--

public class ImprovedClock{

	private volatile long first = 0, second = 0;
	private volatile boolean startPressed = false, stopPressed = false;

	public void start(){
		if(!startPressed){
			synchronized(this){
				first = System.currentTimeMillis();
				startPressed = true;
				stopPressed = false;
			}
		}
	}

	public boolean hasStarted(){
		return startPressed;
	}

	public void stop(){
		if(!stopPressed){
			synchronized(this){
				second = System.currentTimeMillis();
				startPressed = false;
				stopPressed = true;
			}
		}
	}

	public boolean hasStopped(){
		return stopPressed;
	}

	public long getElapsedTime(){
		long time = 0;
		synchronized(this){
			time = second - first;
			first = 0;
			second = 0;
		}
		return time;
	}

	public double getSeconds(){
		return ((double)getElapsedTime()/1000);
	}
}

import javax.swing.JFrame;
import java.awt.event.KeyEvent;
import java.awt.event.KeyAdapter;

public class TimeMonitorTest extends JFrame{


	public TimeMonitorTest(){
		final ImprovedClock ic = new ImprovedClock();
		addKeyListener(
			new KeyAdapter(){
				@Override public void keyPressed(KeyEvent ke){
					if(!ic.hasStarted()){
						ic.start();
						System.out.println("Clock started!");
					}
				}

				@Override public void keyReleased(KeyEvent ke){
					ic.stop();
					System.out.println("Time elapsed: " + ic.getSeconds() + " seconds!");
				}
			}
		);
		setSize(300, 300);
                setLocation(500, 500);
		setVisible(true);
	}

	public static void main(String... args){
		TimeMonitorTest tmt = new TimeMonitorTest();
	}
}

To make this work simply focus the pane (by clicking it) and key events will be listened for. Hold down a key then when you release it the seconds the key was held down will be displayed.

[esy928]

cool!!! thanks edwards!! =)