A simple basic question: calling a method return...

[gerard_pp]

Hello

First of all, please excuse my english. I`ll do my best to explain myself.

I have readed some java books, but i still don´t have the practical experience to deal with the developing of serius java applications. My goal is to program java games, and that´s why im here asking my fist nooby question:

I wanna register on a "drawString" line, whenever the player hits any key on the keyboard. i was guessing to put it inside my paint method, but it keeps giving me an error.

Here is the code. Can someone help me:

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import java.applet.*; import java.awt.*; public class Prueba extends Applet implements Runnable{    Thread t;    int i;        public void init(){       t = new Thread(this);       t.start();             i = 0;    }        public void run(){       while(true){          i++;          repaint();                    try{             t.sleep(1000/30);          }catch(Exception ex){          }         }    }    public void paint(Graphics g){       g.drawString("i = "+i, 10, 20);             g.drawString("message", 50, 80);    }    public boolean keyDown(Event e, int key)    {      String message = "value = " + key;      return true;    }     }

[roland]

Please output the error you get.

firstly,

1	String message = "value = " + key;

you don't do anything with this. I think you want to make message a field instead of local variable.
Then you can say:

1	g.drawString(message, 50, 80);

instead of

1	g.drawString("message", 50, 80);

You also need your class to implement KeyListener and go

1	addKeyListener(this);

in the init method

[gerard_pp]

Thanks for the response.

For some reason i cannot see the message of the key being pressed. I get this error:

at java.awt.EventDispatchThread.pumpEvents(Unknown Source)

Here is my code with modifications:

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import java.applet.*; import java.awt.*; import java.awt.event.*; public class Prueba extends Applet implements Runnable, KeyListener{    String message;    Thread t;    int i;        public void init(){       addKeyListener(this);       t = new Thread(this);       t.start();             i = 0;    }        public void run(){       while(true){          i++;          repaint();                    try{             t.sleep(1000/30);          }catch(Exception ex){;}         }    }    public void paint(Graphics g){       g.drawString("i = "+i, 10, 20);       g.drawString(message, 50, 80);    }    public void keyPressed(KeyEvent e) {         message = "KEY PRESSED: " + e;     }    public void keyTyped(KeyEvent e) {;}    public void keyReleased(KeyEvent e) {;} }

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[ra4king]

That's not the entire exception, but it's most likely NullPointerException because the variable "message" is null and you can't draw null strings

[gbeebe]

Change the line that reads:

1	String message;

to:

1	String message = "";

also, ra4king beat me to it, because I didn't realize I wasn't logged in, and couldn't remember my password

[gerard_pp]

Thank you all guys. Now it's working.