Is there a way to hide all elements in JFrame

Question

I'm currently working on Java application and I'm using JFrame and inside of JFrame i have some buttons, labels and textfields. I'm in need of hiding all the elements that are in JFrame. I don't need to hide JFrame itself, only the elements in it so I can display some others. Is there a way to hide them all without

Accepted Answer

Add the components you want to control to a common container, then simply hide/show itimport java.awt.BorderLayout;import java.awt.EventQueue;import java.awt.GridBagLayout;import java.awt.Insets;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;import javax.swing.border.EmptyBorder;public class Test { public static void main(String[] args) { new Test(); } public Test() { EventQueue.invokeLater(new Runnable() { @Override public void run() { JFrame frame = new JFrame(); frame.add(new TestPane()); frame.pack(); frame.setLocationRelativeTo(null); frame.setVisible(true); } }); } public class TestPane extends JPanel { public TestPane() { setBorder(new EmptyBorder(new Insets(8, 8, 8, 8))); setLayout(new BorderLayout()); JPanel basePane = new JPanel(new GridBagLayout()); basePane.setBorder(new EmptyBorder(new Insets(50, 50, 50, 50))); basePane.add(new JLabel("I can see you")); add(basePane); JButton btn = new JButton("Hide"); add(btn, BorderLayout.SOUTH); btn.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { if (basePane.isVisible()) { basePane.setVisible(false); btn.setText("Show"); } else { basePane.setVisible(true); btn.setText("Hide"); } } }); } }}I think this will not do the job …Actually, I think it will, but, you’re missing a number very important, core concepts.DecoupleYou’re operating in a OO language, one of things you’re going to want to focus on is “decoupling” the dependencies your functionality has to other functionality. Ask yourself the simple question. If I had to modify this one part of the system, what ramifications will it have. If you find yourself in a cascade of changes, then your system is to tightly coupledSingle responsibilityYou want to isolate functionality, as much as possible, so that it has one single job to do. Rather then using a “god” class (like you have), which tries to do everything, break down your problem into small chunks an isolate the functionality, so that it’s doing as simple a job as it possibly can.As much as possible, each element shouldn’t be reliant on knowing the current state of the system, beyond what it’s been told, which is part of the first and third points.Dependency injectionPass the information that each sub system needs to them, rather than having globally reachable resources. This is really good for testing, but it further reduces the couplingCode to interfaceMake use of interface to describe high level concepts of functionality. For example, the “student details” view doesn’t care about how the student information is structured, obtained or managed, it only cares about presenting some information maintained by the interface (or contract). This will make it easier to make core changes to the underlying implementation without adversely effecting all those parts of the system which want to use it, as they are only relying on the “contract” defined by the interfaceExample…Now, typically, I use a CardLayout, but a CardLayout isn’t as dynamic as something like this problem might need.So, instead, I rolled my own “navigation” workflow. This allows me more control over the information which needs to be injected and allows for a more dynamic presentation – you don’t want to present the student login screen filled in with the student credentials when a student logs out.import java.awt.BorderLayout;import java.awt.EventQueue;import java.awt.GridBagConstraints;import java.awt.GridBagLayout;import java.awt.Insets;import java.awt.Window;import java.awt.event.ActionEvent;import java.awt.event.ActionListener;import java.util.ArrayDeque;import java.util.Deque;import javax.swing.JButton;import javax.swing.JFrame;import javax.swing.JLabel;import javax.swing.JOptionPane;import javax.swing.JPanel;import javax.swing.JPasswordField;import javax.swing.JTextField;import javax.swing.SwingUtilities;import javax.swing.border.EmptyBorder;public class Test { public static void main(String[] args) { new Test(); } public Test() { EventQueue.invokeLater(new Runnable() { @Override public void run() { JFrame frame = new JFrame(); frame.setTitle("Študentský systém"); frame.add(new MainPane()); frame.pack(); frame.setLocationRelativeTo(null); frame.setVisible(true); } }); } public interface Authenticator { public Student authenticateStudent(String userName, char[] password); public void logout(Student student); } // This is how you would return information public interface Student { } // You'll need to fill this out... public class DefaultAuthenticator implements Authenticator { @Override public Student authenticateStudent(String userName, char[] password) { return null; } @Override public void logout(Student student) { } } public class NavigationManager { private Deque viewHierarchy = new ArrayDeque<>(16); private JPanel parent; public NavigationManager(JPanel parent) { this.parent = parent; } protected void push(JPanel view) { viewHierarchy.add(view); present(view); } protected void present(JPanel view) { parent.removeAll(); parent.add(view); parent.revalidate(); Window window = SwingUtilities.windowForComponent(parent); if (window != null) { window.pack(); window.setLocationRelativeTo(null); } parent.repaint(); } protected void pop() { if (viewHierarchy.size() > 1) { viewHierarchy.removeLast(); } present(viewHierarchy.getLast()); } } public class MainPane extends JPanel { private MenuPane menuPane; private Authenticator authenticator = new DefaultAuthenticator(); private NavigationManager navigationManager; public MainPane() { setLayout(new BorderLayout()); navigationManager = new NavigationManager(this); push(getMenuPane()); } protected void push(JPanel view) { navigationManager.push(view); } protected void pop() { navigationManager.pop(); } protected void present(JPanel view) { navigationManager.present(view); } protected Authenticator getAuthenticator() { return authenticator; } protected MenuPane getMenuPane() { if (menuPane == null) { menuPane = new MenuPane(new MenuPane.NavigationController() { @Override public void presentAdmin() { } @Override public void presentStudent() { present(getStudentLoginPane()); } }); } return menuPane; } protected StudentLoginPane getStudentLoginPane() { return new StudentLoginPane(getAuthenticator(), new StudentLoginPane.NavigationController() { @Override public void back() { pop(); } @Override public void studentAuthentictated(Student student) { push(getStudentDetailsPane(student)); } }); } protected StudentPane getStudentDetailsPane(Student student) { return new StudentPane(student, new StudentPane.NavigationController() { @Override public void logout(Student student) { getAuthenticator().logout(student); pop(); } }); } } public class MenuPane extends JPanel { public static interface NavigationController { public void presentAdmin(); public void presentStudent(); } private JButton adminBtn; private JButton studentBtn; private JLabel title; public MenuPane(NavigationController navigationController) { setLayout(new GridBagLayout()); setBorder(new EmptyBorder(new Insets(25, 25, 25, 25))); adminBtn = new JButton("Admin"); studentBtn = new JButton("Študent"); title = new JLabel("Zvoľ typ prihlásenia"); GridBagConstraints gbc = new GridBagConstraints(); gbc.fill = GridBagConstraints.HORIZONTAL; gbc.gridwidth = GridBagConstraints.REMAINDER; gbc.insets = new Insets(4, 4, 4, 4); add(title, gbc); add(adminBtn, gbc); add(studentBtn, gbc); adminBtn.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { navigationController.presentAdmin(); } }); studentBtn.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { navigationController.presentStudent(); } }); } } public class StudentLoginPane extends JPanel { public static interface NavigationController { public void back(); public void studentAuthentictated(Student student); } private JLabel title; private JButton signInBtn; private JButton backBtn; private JLabel loginLabel; private JLabel passwordLabel; private JTextField userNameField; private JTextField passwordField; public StudentLoginPane(Authenticator authenticator, NavigationController navigationController) { title = new JLabel("Študentský systém"); title.setHorizontalAlignment(JLabel.CENTER); title.setBorder(new EmptyBorder(16, 16, 16, 16)); signInBtn = new JButton("Prihlásiť"); backBtn = new JButton("Späť"); loginLabel = new JLabel("Login:"); passwordLabel = new JLabel("Heslo:"); userNameField = new JTextField(10); passwordField = new JPasswordField(10); setLayout(new BorderLayout()); add(title, BorderLayout.NORTH); JPanel contentPane = new JPanel(new GridBagLayout()); GridBagConstraints gbc = new GridBagConstraints(); gbc.gridx = 0; gbc.gridy = 0; gbc.anchor = GridBagConstraints.LINE_END; gbc.insets = new Insets(4, 4, 4, 4); contentPane.add(loginLabel, gbc); gbc.gridy++; contentPane.add(passwordLabel, gbc); gbc.anchor = GridBagConstraints.LINE_START; gbc.gridx = 1; gbc.gridy = 0; contentPane.add(userNameField, gbc); gbc.gridy++; contentPane.add(passwordField, gbc); add(contentPane); JPanel buttonPane = new JPanel(new GridBagLayout()); buttonPane.setBorder(new EmptyBorder(16, 16, 16, 16)); buttonPane.add(signInBtn); buttonPane.add(backBtn); add(buttonPane, BorderLayout.SOUTH); signInBtn.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { // Perform the required authentication // If you're wondering, yes, I'd probably pass in a reference // to a "authenticator" which would do the actual work for // me // Passing null here is just for demonstration purposes navigationController.studentAuthentictated(null); } }); backBtn.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { navigationController.back(); } }); } } public class StudentPane extends JPanel { public static interface NavigationController { public void logout(Student student); } private JLabel idLabel; private JLabel nameLabel; private JLabel groupLabel; // And here we have a demonstration of a decoupled workflow // The MainPane shouldn't care about anything other then logging // the student out, all other "sub flows" can become the responsbility // of the sub views themselves private NavigationManager navigationManager; public StudentPane(Student student, NavigationController navigationController) { navigationManager = new NavigationManager(this); idLabel = new JLabel("560269"); // Use the reference to student to get this nameLabel = new JLabel("Marek Magula"); // Use the reference to student to get this groupLabel = new JLabel("5ZYS11"); // Use the reference to student to get this setLayout(new BorderLayout()); JPanel detailsPane = new JPanel(new GridBagLayout()); GridBagConstraints gbc = new GridBagConstraints(); gbc.gridx = 0; gbc.gridy = 0; gbc.anchor = GridBagConstraints.LINE_END; gbc.insets = new Insets(4, 4, 4, 4); detailsPane.add(new JLabel("ID:"), gbc); gbc.gridy++; detailsPane.add(new JLabel("Meno:"), gbc); gbc.gridy++; detailsPane.add(new JLabel("Študijná skupina:"), gbc); add(detailsPane, BorderLayout.NORTH); gbc.gridx = 1; gbc.gridy = 0; gbc.anchor = GridBagConstraints.LINE_START; detailsPane.add(idLabel, gbc); gbc.gridy++; detailsPane.add(nameLabel, gbc); gbc.gridy++; detailsPane.add(groupLabel, gbc); JButton subjectsBtn = new JButton("Predmety"); JButton optioinalSubjectsBtn = new JButton("Voliteľné predmety"); JButton changePassword = new JButton("Zmeniť heslo"); JButton profileBtn = new JButton("Profilové údaje"); JButton logoutBtn = new JButton("Odhlásiť"); JPanel buttonPane = new JPanel(new GridBagLayout()); gbc = new GridBagConstraints(); gbc.gridwidth = gbc.REMAINDER; gbc.fill = gbc.HORIZONTAL; gbc.ipadx = 8; gbc.ipady = 8; gbc.insets = new Insets(4, 4, 4, 4); buttonPane.add(subjectsBtn, gbc); buttonPane.add(optioinalSubjectsBtn, gbc); buttonPane.add(changePassword, gbc); buttonPane.add(profileBtn, gbc); buttonPane.add(logoutBtn, gbc); add(buttonPane); subjectsBtn.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { // Create a student's subject pane; // Inject in the student reference // Use the NavigationManager to push it onto the stack } }); optioinalSubjectsBtn.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { // Create a student's optional subject pane; // Inject in the student reference // Use the NavigationManager to push it onto the stack } }); changePassword.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { // Okay, this is one of those "questionable" options // Is it better to pass the a reference of the // "authenticator" service to this class, then use a // simple dialog to get the password from the user // and then pass it to the "authenticator" service // OR // should we present another screen?! // Personally, I prefer option 1 JOptionPane.showMessageDialog(StudentPane.this, "All your password belong to us"); } }); profileBtn.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { // Create a student's profile pane; // Inject in the student reference // Use the NavigationManager to push it onto the stack } }); logoutBtn.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { navigationController.logout(student); } }); } }}This is an incomplete implementation, only intended to provide a jumping off point.I strongly encourage you to have look at Laying Out Components Within a Container

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Answer

Decouple

Single responsibility

Dependency injection

Code to interface

Example…