ademas implementando WindowsListener, ActionListener, KeyListener para gestionar los eventos de los
botones.
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import java.awt.*;
import java.awt.event.*;
public class DibujoPrueba extends Frame implements WindowListener,ActionListener,KeyListener {
//ELEMENTOS DE NUESTRO FRAME
private Label L1,L2,L3,L4,L5=null;
private Label V1,V2,V3,V4,V5,V6=null;
private TextField T1,T2,T3,T4,T5,T6,T7,T8=null;
private Button calculo=null;
private Button limpio=null;
//CONSTRUCTORES
public DibujoPrueba(){
super();
configurarFrame();
}
public DibujoPrueba(String titulo){
super(titulo);
configurarFrame();
}
public void keyPressed(KeyEvent e){
Object ob=e.getSource();
char tecla=e.getKeyChar();
if(ob.equals(T1)){
if(tecla=='\n'){
T2.requestFocus();
}
}
if(ob.equals(T2)){
if(tecla=='\n'){
T3.requestFocus();
}
}
if(ob.equals(T3)){
if(tecla=='\n'){
T4.requestFocus();
}
}
if(ob.equals(T4)){
if(tecla=='\n'){
T5.requestFocus();
}
}
if(ob.equals(T5)){
if(tecla=='\n'){
T6.requestFocus();
}
}
if(ob.equals(T6)){
if(tecla=='\n'){
calcular();
}
}
}
public void keyReleased(KeyEvent e){}
public void keyTyped(KeyEvent e){}
public void aclarar(){
T1.setText("");
T2.setText("");
T3.setText("");
T4.setText("");
T5.setText("");
T6.setText("");
T7.setText("");
T8.setText("");
}
public void calcular(){
double x1=0;
double y1=0;
double x2=0;
double y2=0;
double x3=0;
double y3=0;
x1=Double.valueOf(T1.getText()).doubleValue();
y1=Double.valueOf(T2.getText()).doubleValue();
x2=Double.valueOf(T3.getText()).doubleValue();
y2=Double.valueOf(T4.getText()).doubleValue();
x3=Double.valueOf(T5.getText()).doubleValue();
y3=Double.valueOf(T6.getText()).doubleValue();
double area=Math.abs((0.5)*(y1*(x2-x3) + y2*(x3-x1) + y3*(x1-x2)));
double lado1=Math.sqrt((x1-x2)*(x1-x2) + (y1-y2)*(y1-y2));
double lado2=Math.sqrt((x2-x3)*(x2-x3) + (y2-y3)*(y2-y3));
double lado3=Math.sqrt((x1-x3)*(x1-x3) + (y1-y3)*(y1-y3));
double perimetro=lado1+lado2+lado3;
T7.setText(String.valueOf(area));
T8.setText(String.valueOf(perimetro));
}
public void actionPerformed(ActionEvent e){
Object ob=e.getSource();
if(ob.equals(calculo)){
calcular();
}
else if(ob.equals(limpio)){
aclarar();
}
}
public static void main(java.lang.String[]args){
DibujoPrueba D1=new DibujoPrueba();
D1.show();
}
private void configurarFrame(){
this.addWindowListener(this);
this.setLayout(null);
this.setBackground(Color.BLUE);
this.setResizable(true);
L1=new Label("VERTICE 1");
L1.setBounds(20,40,70,20);
add(L1);
L2=new Label("VERTICE 2");
L2.setBounds(20,60,70,20);
add(L2);
L3=new Label("VERTICE 3");
L3.setBounds(20,80,70,20);
add(L3);
L4=new Label("AREA");
L4.setBounds(20,120,70,20);
add(L4);
L5=new Label("PERIMETRO");
L5.setBounds(20,140,80,20);
add(L5);
V1=new Label("X1");
V1.setBounds(160,40,100,20);
add(V1);
V2=new Label("Y1");
V2.setBounds(450,40,100,20);
add(V2);
V3=new Label("X2");
V3.setBounds(160,60,100,20);
add(V3);
V4=new Label("Y2");
V4.setBounds(450,60,100,20);
add(V4);
V5=new Label("X3");
V5.setBounds(160,80,100,20);
add(V5);
V6=new Label("Y3");
V6.setBounds(450,80,100,20);
add(V6);
T1=new TextField();
T1.setBounds(270,40,80,20);
T1.addKeyListener(this);
add(T1);
T2=new TextField();
T2.setBounds(560,40,80,20);
T2.addKeyListener(this);
add(T2);
T3=new TextField();
T3.setBounds(270,60,80,20);
T3.addKeyListener(this);
add(T3);
T4=new TextField();
T4.setBounds(560,60,80,20);
T4.addKeyListener(this);
add(T4);
T5=new TextField();
T5.setBounds(270,80,80,20);
T5.addKeyListener(this);
add(T5);
T6=new TextField();
T6.setBounds(560,80,80,20);
T6.addKeyListener(this);
add(T6);
T7=new TextField();
T7.setBounds(140,120,100,20);
T7.addKeyListener(this);
add(T7);
T8=new TextField();
T8.setBounds(140,140,100,20);
T8.addKeyListener(this);
add(T8);
calculo=new Button("CALCULAR");
calculo.setBounds(20,160,100,20);
calculo.addActionListener(this);
add(calculo);
limpio=new Button("RESET");
limpio.setBounds(20,180,100,20);
limpio.addActionListener(this);
add(limpio);
setSize(700,210);
setLocation(200,200);
}
public void windowActivated(WindowEvent e){}
public void windowClosed(WindowEvent e){}
public void windowClosing(WindowEvent e){
Window w=e.getWindow();
if(w.equals(this)){
this.dispose();
System.exit(0);
}
}
public void windowDeactivated(WindowEvent e){}
public void windowDeiconified(WindowEvent e){}
public void windowIconified(WindowEvent e){}
public void windowOpened(WindowEvent e){}
}
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Aqui , podemos ver el resultado de nuestro pequeño codigo.
