Question :
I’m starting in Java and want to make a screen where the person signs the login and the password, the system stores the data and then in a new window is asked to enter the user and password, I did the part of validation and registration of the data on the same page, since I do not dominate the JFrames .
How do I separate things, for example create a page and then close it and open a new one? I do not know where I can close the code and open a new one, for example.
Follow the current code, I’m working with Eclipse.
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class Exemplo1 extends JFrame implements ActionListener{
JButton entrar;
JTextField cxnome;
JTextField cxsenha;
JLabel rotulo;
JTextField cxvarnome; //variavel de senha a ser inserida
JTextField cxvarsenha; //variavel de senha a ser inserida
public void actionPerformed(ActionEvent evento){
String nome, senha, suasenha, seunome;
nome = cxnome.getText();
senha = cxsenha.getText();
seunome = cxvarnome.getText();
suasenha = cxvarsenha.getText();
//metodo da interface ActionListener
//como o tipo String não é um tipo primitivo, e sim
//um tipo referencial, sua comparação não pode ser ==
if (evento.getSource()== entrar && nome.equals(seunome)&& senha.equals(suasenha)){
rotulo.setText("CORRETO");
dispose();
}
else{
rotulo.setText("FALHO");
}
}
public static void main(String[] args){
//instanciando objeto
Exemplo1 janela = new Exemplo1();
janela.setVisible(true);
janela.setTitle("login");
janela.setSize(200,200);
janela.setLocation(400,300);
}
//construtor
public Exemplo1(){
//gride para os objetos
getContentPane().setLayout(new GridLayout(4,1));
cxvarnome = new JTextField();//instanciando
getContentPane().add(cxvarnome);//coloca... no grid
cxvarsenha = new JTextField();//instanciando
getContentPane().add(cxvarsenha);//coloca... no grid
cxnome = new JTextField();//instanciando
getContentPane().add(cxnome);//coloca... no grid
cxsenha = new JTextField();//instanciando
getContentPane().add(cxsenha);//coloc... no grid
entrar = new JButton("OK");//instanciando
getContentPane().add(entrar);//coloca... no grid
entrar.addActionListener(this);//add evento ao clicar
rotulo = new JLabel();//instanciando
getContentPane().add(rotulo);//coloca... no grid
rotulo.setOpaque(true);//tornando opaco
rotulo.setBackground(Color.orange);
}
}
Answer :
Use CardLayout that allows you to work with multiple JPanel in of Container . With this layout you can easily control the flow of the panels using methods to toggle them:
first(C) // Alterna para o primeiro painel adicionado no container (C).
last(C) // Alterna para o último painel inserido no container (C).
next(C) // Muda para o painel seguinte em (C).
previous(C) // Muda para o painel anterior em (C).
show(C, N) // Alterna para o painel com nome (N) dentro do container (C).
This would avoid creating an application with multiple JDialog and / or JFrame .
_
In your code you are inserting all components directly into JFrame . One improvement to make is to separate the two views (Registry and Login) you want into JPanel different.
// Painel de criação do usuário
JPanel registerView = new JPanel();
// Painel de login
JPanel loginView = new JPanel();
To avoid adding everything directly to JFrame , a “root” panel can be created where everything will happen inside it (and it will have CardLayout as layout).
/*
* É importante armazenar em uma variável para podermos controlar o fluxo
* dentro do JPanel através dos métodos listados no início dessa resposta.
*/
CardLayout card = new CardLayout();
// JPanel onde serão inseridos os JPanels
JPanel rootPanel = new JPanel();
rootPanel.setLayout(card); // definindo o layout
Finally, just add the registration and login panels within rootPanel . Here, the way to add is slightly different from the simple jframe.add(jpanel) , in addition to the component we want to add, we also need to pass a unique name so we can identify it.
//Inserindo os painéis de Registro e Login,
rootPanel.add(registerView, "register");
rootPanel.add(loginView, "login");
// Painel que será exibido primeiro
card.show(rootPanel, "register"); // mostrará o painel com nome "register"
Test code
//Window.java
import java.awt.CardLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
public final class Window extends JFrame {
public Window(String title){
super(title);
init();
}
// Inicializa os componentes
public void init(){
setSize(300,300);
setLocationRelativeTo(null);
setDefaultCloseOperation(EXIT_ON_CLOSE);
// Painel de criação do usuário
JPanel registerView = new JPanel();
registerView.setLayout(null);
// Botão que avançará para o próximo painel.
JButton btnNext = new JButton("Me Registrei! Próximo Painel");
btnNext.setBounds(50, 100, 200, 35);
registerView.add(btnNext);
// Painel de login
JPanel loginView = new JPanel();
loginView.setLayout(null);
JLabel lblLoginPanel = new JLabel("Esse é o painel de login");
lblLoginPanel.setBounds(70, 100, 150, 35);
loginView.add(lblLoginPanel);
CardLayout card = new CardLayout();
// JPanel onde serão inseridos os JPanels
JPanel rootPanel = new JPanel();
rootPanel.setLayout(card); // definindo o layout
getContentPane().add(rootPanel);
// Inserindo os painéis de Registro e Login,
rootPanel.add(registerView, "register");
rootPanel.add(loginView, "login");
card.show(rootPanel, "register"); // mostrará o painel de registro
// Quando clicado...
btnNext.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
card.next(rootPanel); // mostra o próximo JPanel dentro do container
}
});
}
}
–
//Main.java
public class Main {
public static void main(String[] args) throws IOException {
new Window("StackOverflow").setVisible(true);
}
}
Result
In your code, you can have the panel advanced when the user clicks, for example, a log completion button after filling in the required fields. The issue of validating the user is apparently already implemented in your code.