public class MathQuiz extends EFrame  
{
 /** The View:  Lay out the GUI components. */

	public MathQuiz()                               
	{	add (new ELabel().text ("Is 121 a perfect square?"));  // 1
		add (new YesRightButton().text ("yes"));               // 2
		add (new NoWrongButton().text ("no"));                 // 3
		add (new ELabel().text ("What is the square of 30?")); // 4
		add (new AnswerField().width (8));     //in characters // 5
		add (new ELabel().picture ("Rome.jpg"));               // 6
		setVisible (true);                                     // 7
	}	//======================


 /** Controllers: React to click of button or ENTER key. */

	private class YesRightButton extends EButton
	{	public void onClick()                                 
		{	this.setText ("right!");                         // 8
		}
	}	//======================


	private class NoWrongButton extends EButton
	{	public void onClick()                                
		{	this.setText ("you're wrong.");                  // 9
		}
	}	//======================


	private class AnswerField extends EField
	{	public void onEnter()                                
		{	if (this.getText().equals ("900"))               //10
				this.setText ("good!");                    //11
			else                                             //12
				this.setText ("you're wrong.");            //13
		}
	}	//======================
}




class MathQuizApp  // to create a frame from the command window
{
	public static void main (String[ ] args) 
	{	new MathQuiz();
	}	//======================
}