Thank you for all your answers.
To simplify the code and take the problems stepby step, i tried to kept only the Frame and the buffer strategy.
Unfortunately, it seems i have another problem : the code behind should normally be working (as far I know...) unfortunatelly the line appears with a probability of 50%...
I tried it on a friend's computer and it is working perfectly fine... How is that possible ?
The main class
public class main {
public static void main(String[] args) {
Fenetre fen = new Fenetre();
}
}
The Frame class, "Fenetre"
import java.awt.Cursor;
import java.awt.Frame;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.Insets;
import java.awt.Point;
import java.awt.RenderingHints;
import java.awt.Shape;
import java.awt.Toolkit;
import java.awt.Window;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.ComponentEvent;
import java.awt.event.ComponentListener;
import java.awt.event.ItemEvent;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.awt.image.BufferStrategy;
import java.io.File;
import java.io.IOException;
import java.util.Iterator;
import javax.imageio.ImageIO;
public class Fenetre extends Frame implements ComponentListener {
int fenHaut = 0;
int fenLarg = 0;
BufferStrategy strategy;
private Graphics backBuffer = null;
private boolean initiated = false;
public Fenetre() {
fenHaut = 720;
fenLarg = 950;
this.setSize(fenLarg, fenHaut);
this.setLocationRelativeTo(null);
this.setResizable(true);
this.setTitle("Alphamega");
addComponentListener(this);
this.addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e) {
System.exit(0);
}
});
this.setVisible(true);
graphicalRender();
}
public void setVisible(boolean b) {
super.setVisible(b);
if (b & !initiated)
init();
}
/**
* initialise l'affichage
*/
private void init() {
setIgnoreRepaint(true);
createBufferStrategy(2);
strategy = getBufferStrategy();
initiated = true;
}
public void componentHidden(ComponentEvent arg0) {
}
public void componentMoved(ComponentEvent arg0) {
}
public void componentResized(ComponentEvent arg0) {
}
public void componentShown(ComponentEvent arg0) {
}
public void graphicalRender(){
backBuffer = strategy.getDrawGraphics();
backBuffer.drawString("Can you see me ?", 100, 200 );
backBuffer.dispose();
strategy.show();
}
}

.

