MonCode

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.GridLayout;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;

import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;


public class Fenetre extends JFrame {

//voir page 249 du PDF
//On déclare trois JPanel et un JLabel.
// L'un contient un GridLayout (pour les nombres), l'autre, un BorderLayout
// Le JLabel par exemple, qui servira d'ecran, est lié au Panel Border en position NORD.

JPanel Border = new JPanel();
BorderLayout disposition = new BorderLayout();

JPanel Grid = new JPanel();
GridLayout touches = new GridLayout(4,3,3,3);

JPanel Opera = new JPanel();
GridLayout Ope = new GridLayout(5,1,0,2); //note : plus le chiffre de gauche est élevé, plus le rendu est petit

JLabel ecran = new JLabel();

private double result;
private String Operateur;
private boolean update = true;
private boolean clicOperator = false;

//Configuration de la fenêtre

public Fenetre(){

Border.setLayout(disposition);
Grid.setLayout(touches);
Opera.setLayout(Ope);

ecran = new JLabel("0");
ecran.setPreferredSize(new Dimension(1, 35));
Border.add(ecran, disposition.NORTH); //Label au Nord
Border.add(Grid, disposition.CENTER); //Le Panel Grid des touches de la cacul' au Sud
Border.add(Opera, disposition.EAST);
ecran.setHorizontalAlignment(JLabel.CENTER);
ecran.setBorder(BorderFactory.createLineBorder(Color.black));

this.setTitle("Calculatrice");
this.setSize(250,300);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.setLocationRelativeTo(null);
this.setContentPane(Border);

// Déclaration des boutons, mis en écoute d'un ActionListener + lié à une classe interne plus bas.

JButton un = new JButton("1");
un.addActionListener(new Boutonun());

JButton deux = new JButton("2");
deux.addActionListener(new Boutondeux());

JButton trois = new JButton("3");
trois.addActionListener(new Boutontrois());

JButton quatre = new JButton("4");
quatre.addActionListener(new Boutonquatre());

JButton cinq = new JButton("5");
cinq.addActionListener(new Boutoncinq());

JButton six = new JButton("6");
six.addActionListener(new Boutonsix());

JButton sept = new JButton("7");
sept.addActionListener(new Boutonsept());

JButton huit = new JButton("8");
huit.addActionListener(new Boutonhuit());

JButton neuf = new JButton("9");
neuf.addActionListener(new Boutonneuf());

JButton zero = new JButton("0");
zero.addActionListener(new Boutonzero());

JButton virgule = new JButton(".");
virgule.addActionListener(new Boutonvirgule());

JButton egale = new JButton("=");
egale.addActionListener(new Boutonegale());

JButton Effacer = new JButton("C");
Effacer.addActionListener(new Boutoneffacer());

JButton Addition = new JButton("+");
Addition.addActionListener(new Boutonaddition());

JButton Soustraction = new JButton("-");
Soustraction.addActionListener(new Boutonsoustraction());

JButton Multiplication = new JButton("*");
Multiplication.addActionListener(new Boutonmultiplication());

JButton Division = new JButton("/");
Division.addActionListener(new Boutondivision());

JButton numbers = new JButton("/");
numbers.addActionListener(new NumberListener());



Grid.add(un);
Grid.add(deux);
Grid.add(trois);
Grid.add(quatre);
Grid.add(cinq);
Grid.add(six);
Grid.add(sept);
Grid.add(huit);
Grid.add(neuf);
Grid.add(zero);
Grid.add(virgule);
Grid.add(egale);

Opera.add(Effacer);
Opera.add(Addition);
Opera.add(Soustraction);
Opera.add(Multiplication);
Opera.add(Division);



this.setVisible(true);
}

// Double result prend la valeur du premier nombre que l'on affiche a l'ecran


class Boutonun implements ActionListener{
public void actionPerformed(ActionEvent arg0) {
result = Double.valueOf(ecran.getText()).doubleValue();
ecran.setText(ecran.getText() + "1");
}
}

class Boutondeux implements ActionListener{
public void actionPerformed(ActionEvent arg0) {
result = Double.valueOf(ecran.getText()).doubleValue();
ecran.setText(ecran.getText() + "2");

}
}


class Boutontrois implements ActionListener{
public void actionPerformed(ActionEvent arg0) {
result = Double.valueOf(ecran.getText()).doubleValue();
ecran.setText(ecran.getText() + "3");
}
}

class Boutonquatre implements ActionListener{
public void actionPerformed(ActionEvent arg0) {
result = Double.valueOf(ecran.getText()).doubleValue();
ecran.setText(ecran.getText() + "4");
}
}

class Boutoncinq implements ActionListener{
public void actionPerformed(ActionEvent arg0) {
result = Double.valueOf(ecran.getText()).doubleValue();
ecran.setText(ecran.getText() + "5");
}
}

class Boutonsix implements ActionListener{
public void actionPerformed(ActionEvent arg0) {
result = Double.valueOf(ecran.getText()).doubleValue();
ecran.setText(ecran.getText() + "6");
}
}

class Boutonsept implements ActionListener{
public void actionPerformed(ActionEvent arg0) {
result = Double.valueOf(ecran.getText()).doubleValue();
ecran.setText(ecran.getText() + "7");
}
}

class Boutonhuit implements ActionListener{
public void actionPerformed(ActionEvent arg0) {
result = Double.valueOf(ecran.getText()).doubleValue();
ecran.setText(ecran.getText() + "8");
}
}

class Boutonneuf implements ActionListener{
public void actionPerformed(ActionEvent arg0) {
result = Double.valueOf(ecran.getText()).doubleValue();
ecran.setText(ecran.getText() + "9");
}
}

class Boutonzero implements ActionListener{
public void actionPerformed(ActionEvent arg0) {
result = Double.valueOf(ecran.getText()).doubleValue();
ecran.setText(ecran.getText() + "0");
}
}

class Boutonvirgule implements ActionListener{
public void actionPerformed(ActionEvent arg0) {
ecran.setText(ecran.getText() + ".");
}
}

//--------------------------------------------------------------------------


private void Calcul(){
if(Operateur.equals("+")){
    result = result + Double.valueOf(ecran.getText()).doubleValue();
    ecran.setText(String.valueOf(result));
    }

    else if (Operateur.equals("-")){
    result = result - Double.valueOf(ecran.getText()).doubleValue();
    ecran.setText(String.valueOf(result));
    }

    else if (Operateur.equals("*")){
    result = result * Double.valueOf(ecran.getText()).doubleValue();
    ecran.setText(String.valueOf(result));
    }

    else if (Operateur.equals("/")){
    result = result / Double.valueOf(ecran.getText()).doubleValue();
    ecran.setText(String.valueOf(result));

    }
}


//-----------------------------------------------------------------------------------

class NumberListener implements ActionListener {

    public void actionPerformed(ActionEvent arg0) {
       String str = ((JButton)arg0.getSource()).getText();

       if (update) {  //si il faut mettre à jour l'écran (reset)
          if (str == ".") {  //si on appuit en premier sur la touche point
             str = ecran.getText() + str;
             ecran.setText(str);
          }
          else {
             ecran.setText(str);
          }
          update = false;
       }
       else {  //si il faut continuer à écrire
          str = ecran.getText() + str;
          ecran.setText(str);
       }
    }
 }


//-----------------------------------------------------------------------------------


class Boutoneffacer implements ActionListener{
public void actionPerformed(ActionEvent arg0) {
ecran.setText("0");
update = true;
}
}

//String Operateur prend la valeur d'un des opérateurs des boutons correspondant

class Boutonaddition implements ActionListener{
public void actionPerformed(ActionEvent arg0) {
if (clicOperator) {
Calcul();
ecran.setText(String.valueOf(result));
}
else {
result = Double.valueOf(ecran.getText()).doubleValue();
clicOperator = true;
}
Operateur = "+";
update = true;
  }

}

class Boutonsoustraction implements ActionListener{
public void actionPerformed(ActionEvent arg0) {

    if (clicOperator) {
        Calcul();
        ecran.setText(String.valueOf(result));
     }
     else {
        result = Double.valueOf(ecran.getText()).doubleValue();
        clicOperator = true;
     }
     Operateur = "-";
     update = true;
  }

}

class Boutonmultiplication implements ActionListener{
public void actionPerformed(ActionEvent arg0) {


    if (clicOperator) {
        Calcul();
        ecran.setText(String.valueOf(result));
     }
     else {
        result = Double.valueOf(ecran.getText()).doubleValue();
        clicOperator = true;
     }
     Operateur = "*";
     update = true;
  }

}

class Boutondivision implements ActionListener{
public void actionPerformed(ActionEvent arg0) {

    if (clicOperator) {
        Calcul();
        ecran.setText(String.valueOf(result));
     }
     else {
        result = Double.valueOf(ecran.getText()).doubleValue();
        clicOperator = true;
     }
     Operateur = "/";
     update = true;
  }

}

//Les calculs ! Selon tel operateur, on prend result, puis le second nombre entré...

class Boutonegale implements ActionListener{
public void actionPerformed(ActionEvent arg0) {
Calcul();
update = true;
clicOperator = false;
Operateur = "";
}


}


       }