Commit

Calculator/src/calc/CalcolatriceMain.java

@@ -0,0 +1,79 @@
+package calc;
+
+import java.awt.event.ActionEvent;
+import java.awt.event.ActionListener;
+import javax.swing.JButton;
+import javax.swing.JFrame;
+import javax.swing.JTextField;
+
+class ButtonHandler implements ActionListener {
+    JTextField tf;
+    int a,b;
+    String op;
+
+    public ButtonHandler(JTextField tf) {
+        this.tf = tf;
+    }
+    @Override
+    public void actionPerformed(ActionEvent e) {
+        if (e.getActionCommand().equals("+") || e.getActionCommand().equals("-")) {
+            op = e.getActionCommand();
+            a = Integer.parseInt(tf.getText());
+            tf.setText("");
+            return;
+        }
+        if (e.getActionCommand().equals("=")) {
+            b = Integer.parseInt(tf.getText());
+            if(op.equals("+")) tf.setText(""+(a+b));
+            if(op.equals("-")) tf.setText(""+(a-b));
+            return;
+        }
+        tf.setText(tf.getText()+e.getActionCommand());
+    }
+}
+
+
+// Classe principale con il metodo main
+public class CalcolatriceMain {
+    public static void main(String[] args) {
+        JFrame f = new JFrame("titolo");
+        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
+        f.setBounds(100, 100, 300, 500);
+        f.setLayout(null);
+
+        JTextField tf = new JTextField("0");
+        tf.setBounds(10, 10, 240, 80);
+        f.add(tf);
+        ButtonHandler bh = new ButtonHandler(tf);
+
+        int x = 10;
+        int y = 100;
+        int cont = 1;
+
+        for (int j = 0; j < 3; j++) {
+            for (int i = 0; i < 3; i++) {
+                JButton bn = new JButton("" + cont);
+                bn.setActionCommand("" + cont);
+                bn.setBounds(x, y, 80, 80);
+                f.add(bn);
+                x += 80;
+                bn.addActionListener(bh);
+                cont++;
+            }
+            y += 80;
+            x = 10;
+        }
+
+        String[] etichette = {"+","-","="};
+        for (int i = 0; i < 3; i++) {
+            JButton bn = new JButton(etichette[i]);
+            bn.setActionCommand(etichette[i]);
+            bn.setBounds(x, y, 80, 80);
+            f.add(bn);
+            x += 80;
+            bn.addActionListener(bh);
+        }
+
+        f.setVisible(true);
+    }
+}