Here is the code I came up with. I am a beginner java programmer who is very confused on what to do. I have to have a "Push me" button and a "Exit" Button created.
The main should also test out this panel. I will need to first instantiate a Frame and then instantiate your ExitPanel and add the ExitPanel to the Frame just before you show the Frame.
What am I doing wrong? Please explain and help thanks.
import javax.swing.*;
import java.awt.*;
import java.awt.FlowLayout;
public class ExitPanel extends JPanel {
public ExitPanel() {
// set flow layout for the frame
this.getContentPane().setLayout(new FlowLayout());
JButton Exit = new JButton();
Exit.setText("Exit");
JButton Push = new JButton("Push Me");
// add buttons to frame
add(Exit);
add(Push);
}
public static void main(String[] args) {
ExitPanel exi = new ExitPanel();
exi.pack();
exi.setVisible(true);
exi.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
}
you are instantaiting a JPanel not a frame
change this:
ExitPanel extends JPanel
to:
ExitPanel extends JFrame
Related
I'm experimenting with desktop panes so I can use them in my work projects. The problem here is that I want to use an JInternalFrame within a JDesktopPane, in a normal JPanel it shows normally but cannot move it, using the desktop pane doesn't display any component added.
Here is the code of the last try, is simple just for learning how it works:
import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
public class Internal_FrameShowtst extends JFrame{
Internal_FrameShowtst(){
BorderLayout bl = new BorderLayout();
JDesktopPane p = new JDesktopPane();
JPanel p1 = new JPanel();
JButton b = new JButton("click");
JInternalFrame in = new JInternalFrame("Test");
Internal_Frametst ift = new Internal_Frametst();
b.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
//p1.add(new JLabel("hola"));
//in.add(p1);
//in.setVisible(true);
ift.setVisible(true);
}
});
p1.add(b);
bl.addLayoutComponent(p,BorderLayout.CENTER);
//p.add(in);
p.add(ift);
p.repaint();
setLayout(bl);
add(p);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
new Internal_FrameShowtst().setVisible(true);
}
});
}
}
custom internal frame class:
import javax.swing.*;
public class Internal_Frametst extends JInternalFrame {
Internal_Frametst(){
JPanel p = new JPanel();
JLabel label = new JLabel("Halo");
setIconifiable(true);
//setIcon(true);
setClosable(true);
p.add(label);
p.setSize(300,300);
add(p);
//setVisible(true);
}
}
I've read and tried the following:
Components inside JDesktopPane not showing
JDesktopPane not displaying components when adding JInternalFrame
I've tried adding the components directly, adding a JPanel, adding the internal frame, trying without it, creating the internal frame in the main class, creating my own internal frame in its own class, using layout managers with both panels (normal and desktop), all with the same result.
Your code creates several components that are never added to the visible UI at all. In the version you have posted, the internal frame is invisible and the button to make it visible is not part of the frame. But there are also problems with the initial sizes of the components.
I strongly recommend to keep the creation of a component, the setting of its initial properties, and the code to add it to a parent component close together in your source code.
Further, consider the points discussed in Prefer composition over inheritance? Your subclasses are entirely unnecessary.
Here is a revised version of your code that will open the internal frame when the button is clicked:
import java.awt.BorderLayout;
import java.awt.EventQueue;
import javax.swing.*;
public class UiExample {
public static void main(String[] args) {
EventQueue.invokeLater(UiExample::initializeUI);
}
static void initializeUI() {
JPanel p1 = new JPanel();
JButton b = new JButton("Show Internal Frame");
p1.add(b);
JInternalFrame ift = initializeInternalFrame();
b.addActionListener(e -> {
ift.pack();
ift.setVisible(true);
});
JDesktopPane p = new JDesktopPane();
p.add(ift);
JFrame mainFrame = new JFrame();
mainFrame.setSize(300, 200);
mainFrame.getContentPane().add(p, BorderLayout.CENTER);
mainFrame.getContentPane().add(p1, BorderLayout.PAGE_START);
mainFrame.setVisible(true);
}
static JInternalFrame initializeInternalFrame() {
JInternalFrame iFrame = new JInternalFrame();
iFrame.setIconifiable(true);
// setIcon(true);
iFrame.setClosable(true);
iFrame.setDefaultCloseOperation(JInternalFrame.HIDE_ON_CLOSE);
JPanel p = new JPanel();
p.add(new JLabel("Hello"));
iFrame.add(p);
return iFrame;
}
}
Note that setDefaultCloseOperation(JInternalFrame.HIDE_ON_CLOSE) is necessary for being able to show the frame again via setVisible(true) after the internal frame has been closed.
I added a button into JPanel and tried to change the size and the position of the button. I've tried different lines of codes but they wont work. Also putting in parent.setLayout(null); or panel.setLayout(null); will just completely remove the button and the background
Here is the code:
import java.awt.BorderLayout;
import java.awt.Color;
import javax.swing.*;
public class app {
public static void main(final String[] args) {
final JFrame parent = new JFrame("CPS TEST");
JButton button = new JButton("Button");
JPanel panel = new JPanel();
panel.setLayout(null);
panel.add(button);
panel.setBackground(Color.DARK_GRAY);
parent.add(panel, BorderLayout.CENTER);
parent.setSize(500, 300);
parent.setBackground(Color.CYAN);
parent.setLocationRelativeTo(null);
parent.setVisible(true);
parent.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
}
Here are three ways to increase the size of a button:
Changing the position of a component is worthy of a separate question, but changing the size of a button is easy.
I have two JFrame.
public class Main extends JFrame
public class ColourOption extends JPanel implements ActionListener which is then set up in a JFrame.
I wanted to open the second JFrame when i click on button of first JFrame
.setVisible() is not working. I also tried revalidate(), as well as invalidate() , validate() in the second JFrame.
What could be the reason for it to not work?
You will have to instantiate the 2nd class which has the 2nd Frame(to be shown)..and then if you call the setVisible(true) .. then it must show .. what you doing .. could you provide your button's event handler..
and this is not good practice
so personally i would recommend you to switch over to better alternatives like JTABBEDPANES or CARDLAYOUT
and consider the comments as well .. good comments guys :) .. especially using JDialog for this context :)
well if you still want help in your context: a sample:
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
class JFrame1 extends JFrame
{
public JFrame1()
{
setLayout(new FlowLayout());
JButton b=new JButton("Click");
add(b);
b.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent ae)
{
JFrame jf = new JFrame2();
jf.setVisible(true);
jf.setSize(200, 200);
jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
}
);
}
public static void main(String args[])
{
JFrame jf = new JFrame1();
jf.setVisible(true);
jf.setSize(200, 200);
jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
}
and the second class:
import javax.swing.*;
import java.awt.*;
class JFrame2 extends JFrame
{
public JFrame2()
{
setLayout(new FlowLayout());
add(new JLabel("2nd Frame"));
}
}
But again i would still recommend to switch to other methods as i mentioned earlier: tabbedpanes, cardlayout etc..
Hope i helped :)
Since they are from 2 different classes, you just have to define/instantiate an object of the other class... and if within that 2nd class (ColourOption) it already contains setVisible(true) then there must be no problem loading the window.
//this will be placed on your constructor
yourButton.addActionListener(new ButtonListener());
//listener class
class ButtonListener implements ActionListener{
public void actionPerformed(ActionEvent ae){
if(ae.getSource() == yourButton){
new ColourOption();
}
}
}
I need to write a simple tennis game.
To move between different windows(panel with main menu, panel with game, panel with settings) I decided to use inner classes extends JPanel and replace it when some events like start new game occurs.
but the problem is - it doesn't see my inner class. I mean I add it to JFrame
mainframe.add(new MainMenuPanel());
but there is nothing on the screen when I run program. What's the problem?
import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
public class MainFrame{
JFrame mainframe;
public static void main(String[] args){
new MainFrame();
}
public MainFrame() {
mainframe = new JFrame();
mainframe.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
mainframe.setSize(300, 400);
mainframe.setTitle("X-Tennis v0.1");
mainframe.add(new MainMenuPanel());
mainframe.getContentPane().setLayout(new GridLayout());
mainframe.getContentPane().setBackground(Color.WHITE);
mainframe.setVisible(true);
}
public class MainMenuPanel extends JPanel {
JPanel mainmenupanel;
JLabel label1;
JButton btnNewGame,btnJoinGame;
ImageIcon iconNewGame,iconJoinGame;
public MainMenuPanel(){
mainmenupanel = new JPanel();
label1 = new JLabel("X-TENNIS");
label1.setFont(new Font("Comic Sans MS",Font.ITALIC,20));
label1.setForeground(Color.BLUE);
btnNewGame = new JButton("New Game", iconNewGame);
btnNewGame.setFocusPainted(false);
btnNewGame.addActionListener(
new ActionListener() {
public void actionPerformed(ActionEvent e){
JOptionPane.showMessageDialog(mainframe, "New game");
//delete current panel and add another to mainframe
}
}
);
btnNewGame.setPreferredSize(new Dimension(140,30));
btnJoinGame = new JButton("Join game",iconJoinGame);
mainmenupanel.add(label1);
mainmenupanel.add(btnNewGame);
}
}
}
There is no need for mainmenupanel within the MainMenuPanel class as MainMenuPanel is a JPanel itself
Simple add all the components in MainMenuPanel directly to itself
You create a new JPanel, mainmenupanel, inside MainMenuPanel but never add that to the container itself. You could do
add(mainmenupanel);
If you intend for this JPanel to occupy the full area of the parent, then you can simply add your components directly to your instance of MainMenuPanel as indicated by #Mad
First you should add your component to the ContentPane. In Swing, all the non-menu components displayed by the JFrame should be in the ContentPane.
mainframe.getContentPane().add(new MainMenuPanel());
Edit: I was wrong about the content pane, see #MadProgrammer comment.
Then you have to add the JPanel that you create in MainMenuPanel to the MainMenuPanel instance itself.
add(mainmenupanel);
But you should probably get rid of that intermediary container itself and add your labels to the MainMenuPanel instance itself:
add(label1);
add(btnNewGame);
mainmenupanel.add(label1);
mainmenupanel.add(btnNewGame);
try this :
super.add(label1);
super.add(btnNewGame);
I am really new to GUI programming in Java, I did a lot of research and I couldn't find an answer to this problem.
I have a simple JFrame with a menu, and inside this JFrame I have a JPanel with a log in form (were users input their username and password), and then I want to change that JPanel to another JPanel depending on what users want to do.
What would be the best way of doing this? I think that stacking JPanels is OK. But after I add new JLayeredPanels in Netbeans they don't stack. I read somewhere that I should use Z ordering or something like that, but I can't find it on the designer view.
Well, thank you very much for your patience!
CardLayout class has a useful API that can serve your requirements. Using methods like next(), first(), last() can be helpful.
I've prepared a simple demonstration of changing panels within a parent panel and/or frame.
Take a look at it:
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class PanelChanger implements ActionListener
{
JPanel panels;
public void init(Container pane)
{
JButton switcher = new JButton("Switch Active Panel!");
switcher.addActionListener(this);
JPanel login = new JPanel();
login.setBackground(Color.CYAN);
login.add(new JLabel("Welcome to login panel."));
JPanel another = new JPanel();
another.setBackground(Color.GREEN);
another.add(new JLabel("Yeah, this is another panel."));
panels = new JPanel(new CardLayout());
panels.add(login);
panels.add(another);
pane.add(switcher, BorderLayout.PAGE_START);
pane.add(panels, BorderLayout.CENTER);
}
public void actionPerformed(ActionEvent evt)
{
CardLayout layout = (CardLayout)(panels.getLayout());
layout.next(panels);
}
public static void main(String[] args)
{
JFrame frame = new JFrame("CardLayoutDemo");
PanelChanger changer = new PanelChanger();
changer.init(frame.getContentPane());
frame.pack();
frame.setVisible(true);
}
}