FileDocCategorySizeDatePackage
Calculator.javaAPI DocExample2387Mon Oct 30 16:14:38 GMT 2000None

Calculator

public class Calculator extends Applet implements ActionListener

Fields Summary
int
currentValue
int
operand1
int
operand2
int
result
int
operation
TextField
calculatorDisplay
Panel
numPanel
Panel
opsPanel
Button
one
Button
plus
Button
equals
Constructors Summary
Methods Summary
public voidactionPerformed(java.awt.event.ActionEvent e)

			if(e.getSource() == one)
			{
				currentValue = currentValue * 10 + 1;
				calculatorDisplay.setText(Integer.toString(currentValue));
			}
							// add code for digit button events here
			else if (e.getSource() == plus)
			{
				operand1     = currentValue;
				currentValue = 0;
				calculatorDisplay.setText("0");
				operation    = 1;
			}
									// add code for operation button events here
			else if (e.getSource() == equals)
			{
				operand2     = currentValue;
				currentValue = 0;
				switch (operation)
				{
					case 1: result = operand1  +  operand2; break;
					case 2: result = operand1  -  operand2; break;
					case 3: result = operand1  *  operand2; break;
					case 4: result = operand1  /  operand2; break;
				}
				calculatorDisplay.setText(Integer.toString(result));
				operand1 = operand2 = 0;
			
			}
public voidinit()


	  
	
		numPanel.setLayout(new GridLayout(4,3,5,5));
		add(calculatorDisplay);
		numPanel.add(one);
								// add new digit buttons to numPanel here		
		opsPanel.setLayout(new GridLayout(2,4, 5, 5));		
		opsPanel.add(plus);
								// add new operation buttons to opsPanel here
		opsPanel.add(equals);
		add(numPanel);
		add(opsPanel);
		
		one.addActionListener(this);
								// add actionListeners for digit buttons here
		plus.addActionListener(this);
								// add actionListeners for operation buttons here
		equals.addActionListener(this);
	
		currentValue = 0;		// set currentValue to 0 before we use it
public voidpaint(java.awt.Graphics g)

		setForeground(Color.blue);
		setBackground(Color.yellow);