Programmation Graphique et Événementielle en Java et C#

Composant (Widget)  → Élément visuel interactif
Conteneur (Container) → Regroupe d'autres composants
Layout Manager      → Organise les composants automatiquement
Événement (Event)   → Action utilisateur (clic, touche, etc.)
Listener/Handler    → Code exécuté en réponse à un événement

// HelloWorld.java - Premier programme graphique Java
import javax.swing.*;

public class HelloWorld {
    public static void main(String[] args) {
        JFrame fenetre = new JFrame("Mon Premier Programme");
        fenetre.setSize(400, 300);
        fenetre.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        JLabel label = new JLabel("Bonjour le Monde !");
        label.setHorizontalAlignment(SwingConstants.CENTER);

        fenetre.add(label);
        fenetre.setVisible(true);
    }
}

// Compilation et exécution :
// $ javac HelloWorld.java
// $ java HelloWorld

using System;
using System.Windows.Forms;

namespace MonPremierProgramme
{
    public class MainForm : Form
    {
        private Label label;

        public MainForm()
        {
            this.Text = "Mon Premier Programme C#";
            this.Size = new System.Drawing.Size(400, 300);

            label = new Label();
            label.Text = "Bonjour le Monde !";
            label.TextAlign = System.Drawing.ContentAlignment.MiddleCenter;
            label.Dock = DockStyle.Fill;

            this.Controls.Add(label);
            this.FormClosed += (s, e) => Application.Exit();
        }

        [STAThread]
        public static void Main()
        {
            Application.EnableVisualStyles();
            Application.Run(new MainForm());
        }
    }
}

import java.awt.*;
public class ExempleLayout extends Frame {
    public ExempleLayout() {
        setTitle("Exemple BorderLayout");
        setSize(500, 350);
        setLayout(new BorderLayout(10, 10));
        add(new Button("NORD"), BorderLayout.NORTH);
        add(new Button("SUD"), BorderLayout.SOUTH);
        add(new Button("EST"), BorderLayout.EAST);
        add(new Button("OUEST"), BorderLayout.WEST);
        add(new Button("CENTRE"), BorderLayout.CENTER);
        addWindowListener(new WindowAdapter() {
            public void windowClosing(WindowEvent e) {
                System.exit(0);
            }
        });
    }
    public static void main(String[] args) {
        new ExempleLayout().setVisible(true);
    }
}

import javax.swing.*;
import javax.swing.table.*;
import java.awt.*;

public class AppSwing extends JFrame {
    private JTable table;
    private DefaultTableModel model;

    public AppSwing() {
        setTitle("Application Swing Avancée");
        setSize(800, 500);
        setDefaultCloseOperation(EXIT_ON_CLOSE);

        String[] colonnes = {"Nom", "Prénom", "Âge"};
        model = new DefaultTableModel(colonnes, 0);
        table = new JTable(model);
        table.setRowHeight(25);

        JScrollPane scroll = new JScrollPane(table);
        add(scroll, BorderLayout.CENTER);

        JPanel form = new JPanel(new GridLayout(4, 2, 5, 5));
        form.add(new JLabel("Nom:"));
        JTextField txtNom = new JTextField();
        form.add(txtNom);
        form.add(new JLabel("Prénom:"));
        JTextField txtPrenom = new JTextField();
        form.add(txtPrenom);

        JButton btnAjouter = new JButton("Ajouter");
        btnAjouter.setBackground(new Color(0, 137, 123));
        btnAjouter.setForeground(Color.WHITE);
        btnAjouter.addActionListener(e -> {
            model.addRow(new Object[]{
                txtNom.getText(), txtPrenom.getText()
            });
            txtNom.setText("");
            txtPrenom.setText("");
        });
        form.add(btnAjouter);
        add(form, BorderLayout.NORTH);
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(() ->
            new AppSwing().setVisible(true));
    }
}

// Exemple complet d'événements Swing
btnClic.addActionListener(e -> lblInfo.setText("Bouton cliqué !"));

btnClic.addMouseListener(new MouseAdapter() {
    public void mouseEntered(MouseEvent e) {
        btnClic.setBackground(new Color(0, 137, 123));
        btnClic.setForeground(Color.WHITE);
    }
    public void mouseExited(MouseEvent e) {
        btnClic.setBackground(null);
        btnClic.setForeground(null);
    }
});

txtSaisie.addKeyListener(new KeyAdapter() {
    public void keyReleased(KeyEvent e) {
        lblInfo.setText("Touche : " +
            KeyEvent.getKeyText(e.getKeyCode()));
    }
});

// Fermeture fenêtre avec WindowAdapter
addWindowListener(new WindowAdapter() {
    public void windowClosing(WindowEvent e) {
        System.exit(0);
    }
});

using System;
using System.Windows.Forms;
using System.Drawing;

public class FormulairePrincipal : Form
{
    private TextBox txtNom;
    private ComboBox cboPays;
    private DataGridView dgvDonnees;
    private Label lblStatut;

    public FormulairePrincipal()
    {
        this.Text = "Gestion de Contacts";
        this.Size = new Size(800, 600);
        this.StartPosition = FormStartPosition.CenterScreen;

        Panel panel = new Panel();
        panel.Size = new Size(250, 350);
        panel.BorderStyle = BorderStyle.FixedSingle;

        var lbl = new Label() { Text = "Nom :", Location = new Point(10,20) };
        txtNom = new TextBox() { Location = new Point(10,45), Width = 220 };

        var btn = new Button() { Text = "Ajouter", Location = new Point(10,120) };
        btn.BackColor = Color.Teal;
        btn.ForeColor = Color.White;
        btn.Click += (s, e) => {
            dgvDonnees.Rows.Add(txtNom.Text, cboPays.Text);
            lblStatut.Text = $"Contact ajouté ! Total : {dgvDonnees.RowCount}";
        };

        dgvDonnees = new DataGridView() { Location = new Point(280,20), Size = new Size(480,350) };
        dgvDonnees.Columns.Add("Nom", "Nom");
        dgvDonnees.Columns.Add("Pays", "Pays");

        lblStatut = new Label() { Text = "Prêt", Dock = DockStyle.Bottom };
        panel.Controls.AddRange(new Control[] { lbl, txtNom, btn });
        this.Controls.AddRange(new Control[] { panel, dgvDonnees, lblStatut });
    }

    [STAThread]
    public static void Main() => Application.Run(new FormulairePrincipal());
}

<!-- MainWindow.xaml -->
<Window x:Class="MonApp.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        Title="Mon Application WPF" Height="500" Width="700">
    <Grid>
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="250"/>
            <ColumnDefinition Width="*"/>
        </Grid.ColumnDefinitions>

        <StackPanel Grid.Column="0" Margin="10">
            <TextBlock Text="Formulaire" FontSize="20" FontWeight="Bold"/>
            <TextBox x:Name="TxtNom" Header="Nom" Margin="0,5" Height="35"/>
            <TextBox x:Name="TxtEmail" Header="Email" Margin="0,5" Height="35"/>
            <ComboBox x:Name="CboPays" Header="Pays" Margin="0,5" Height="35">
                <ComboBoxItem Content="Congo"/>
                <ComboBoxItem Content="France"/>
                <ComboBoxItem Content="Belgique"/>
            </ComboBox>
            <Button Content="Ajouter" Background="#00897b" Foreground="White"
                    Padding="15,8" Click="BtnAjouter_Click" Margin="0,10"/>
        </StackPanel>

        <DataGrid x:Name="GrilleDonnees" Grid.Column="1"
                  AutoGenerateColumns="False" Margin="10">
            <DataGrid.Columns>
                <DataGridTextColumn Header="Nom" Binding="{Binding Nom}"/>
                <DataGridTextColumn Header="Email" Binding="{Binding Email}"/>
            </DataGrid.Columns>
        </DataGrid>
    </Grid>
</Window>

public class ContactViewModel : INotifyPropertyChanged
{
    private string _nom;
    public string Nom {
        get => _nom;
        set { _nom = value; OnPropertyChanged(); }
    }

    public ObservableCollection<Contact> Contacts { get; }

    public ICommand AjouterCommand { get; }

    public ContactViewModel() {
        Contacts = new ObservableCollection<Contact>();
        AjouterCommand = new RelayCommand(AjouterContact);
    }

    public event PropertyChangedEventHandler PropertyChanged;
    protected void OnPropertyChanged([CallerMemberName] string n = null)
        => PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(n));
}

// Déclaration d'un type délégué
public delegate double OperationMath(double a, double b);

public class DemoDelegues
{
    public static double Addition(double a, double b) => a + b;
    public static double Multiplication(double a, double b) => a * b;

    // Utilisation basique
    public static void Main()
    {
        OperationMath op = Addition;
        Console.WriteLine(op(5, 3));  // 8

        // Délégué multicast
        OperationMath multiOp = Addition;
        multiOp += Multiplication;
        multiOp(5, 3); // Appelle Addition puis Multiplication

        // Func (délégué générique intégré)
        Func<double, double, double> moyenne = (a, b) => (a + b) / 2;
        Console.WriteLine(moyenne(10, 20));  // 15

        // Action (délégué sans retour)
        Action<string> logger = Console.WriteLine;
        logger += msg => File.AppendAllText("log.txt", msg);
        logger("Application démarrée"); // Écrit dans console ET fichier
    }
}

public class Thermometre
{
    public event EventHandler<TemperatureArgs> TemperatureCritique;
    private double _temperature;

    public double Temperature {
        set {
            _temperature = value;
            if (_temperature >= 100)
                TemperatureCritique?.Invoke(this,
                    new TemperatureArgs(_temperature, "Ébullition !"));
        }
    }
}

// Abonné
var thermo = new Thermometre();
thermo.TemperatureCritique += (sender, e) => {
    Console.WriteLine($"ALERTE : {e.Message} ({e.Temperature}C)");
};
thermo.Temperature = 100;  // Déclenche l'événement

public class Calculatrice extends JFrame {
    private JTextField ecran = new JTextField("0");
    private double premierNombre = 0;
    private String operateur = "";
    private boolean nouveauNombre = true;

    public Calculatrice() {
        setTitle("Calculatrice Java Swing");
        setSize(350, 450);
        ecran.setEditable(false);
        ecran.setFont(new Font("Arial", Font.BOLD, 28));
        ecran.setHorizontalAlignment(JTextField.RIGHT);
        add(ecran, BorderLayout.NORTH);

        String[] btns = {"C","←","%","÷","7","8","9","×",
                         "4","5","6","-","1","2","3","+","+/-","0",".","="};
        JPanel panel = new JPanel(new GridLayout(5, 4, 5, 5));
        for (String txt : btns) {
            JButton btn = new JButton(txt);
            btn.setFont(new Font("Arial", Font.BOLD, 18));
            if (txt.equals("=")) {
                btn.setBackground(new Color(0, 137, 123));
                btn.setForeground(Color.WHITE);
            }
            btn.addActionListener(e -> gererClic(txt));
            panel.add(btn);
        }
        add(panel);
    }

    private void gererClic(String txt) {
        if (txt.matches("[0-9]")) {
            ecran.setText(nouveauNombre ? txt : ecran.getText() + txt);
            nouveauNombre = false;
        } else if (txt.equals("=")) {
            double b = Double.parseDouble(ecran.getText());
            double r = switch(operateur) {
                case "+" -> premierNombre + b;
                case "-" -> premierNombre - b;
                case "×" -> premierNombre * b;
                case "÷" -> b != 0 ? premierNombre / b : throw new ArithmeticException();
                default -> b;
            };
            ecran.setText(String.valueOf(r));
            nouveauNombre = true;
        } else if (txt.matches("[+\\-×÷%]")) {
            premierNombre = Double.parseDouble(ecran.getText());
            operateur = txt;
            nouveauNombre = true;
        } else if (txt.equals("C")) {
            ecran.setText("0"); operateur = ""; nouveauNombre = true;
        }
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(() -> new Calculatrice().setVisible(true));
    }
}