I'm working on an assignment for class where we need to create a JComboBox and each option opens a new window where you can do whatever you want on those new windows. Please keep in mind I'm very new to GUI and new to Java in general, in case my questions are dumb.
I have a question and an issue...
My question:
When the user selects "The Matrix" option a new window pops up with a quote and two buttons. Right now I have two JPanels (panel and panel2) panel adds the quote to the NORTH position and then panel2 adds the two buttons to the CENTER position both using BorderLayout. My question is am I doing this correctly...Could I use just panel to add the quote and the buttons or is it necessary to create separate panels for separate items being added to the JFrame? When I had them both added to the same panel the quote was not on the window when I ran the program.
panel.add(matrixQuote);
newFrame.add(panel, BorderLayout.NORTH);
That's how I had it when it wasn't showing up ^^^
I GOT THE ISSUE WITH CLEARING THE JFRAME FIXED
I am trying to add an ActionListener to the bluePill button and instead of opening another new window I thought I could clear everything from the existing window when the button is pressed and then display something new on said window. The only info I could find on this is how I have it in the actionPerformed method below. I'll post a snippet of what I'm talking about directly below and then all my code below that just in case.
All my code...
public class MultiForm extends JFrame{
private JComboBox menu;
private JButton bluePill;
private JButton redPill;
private JLabel matrixQuote;
private int matrixSelection;
private JFrame newFrame;
private JPanel panel;
private JPanel panel2;
private static String[] fileName = {"", "The Matrix", "Another Option"};
public MultiForm() {
super("Multi Form Program");
setLayout(new FlowLayout());
menu = new JComboBox(fileName);
add(menu);
TheHandler handler = new TheHandler();
menu.addItemListener(handler);
}
public void matrixPanel() {
TheHandler handler = new TheHandler();
//Create a new window when "The Matrix" is clicked in the JCB
newFrame = new JFrame();
panel = new JPanel();
panel2 = new JPanel();
newFrame.setLayout(new FlowLayout());
newFrame.setSize(500, 300);
newFrame.setDefaultCloseOperation(newFrame.EXIT_ON_CLOSE);
matrixQuote = new JLabel("<html>After this, there is no turning back. "
+ "<br>You take the blue pill—the story ends, you wake up "
+ "<br>in your bed and believe whatever you want to believe."
+ "<br>You take the red pill—you stay in Wonderland, and I show"
+ "<br>you how deep the rabbit hole goes. Remember: all I'm "
+ "<br>offering is the truth. Nothing more.</html>");
panel2.add(matrixQuote);
newFrame.add(panel2, BorderLayout.NORTH);
//Blue pill button and picture.
Icon bp = new ImageIcon(getClass().getResource("Blue Pill.png"));
bluePill = new JButton("Blue Pill", bp);
panel2.add(bluePill);
bluePill.addActionListener(handler);
//Red pill button and picture
Icon rp = new ImageIcon(getClass().getResource("Red Pill.png"));
redPill = new JButton("Red Pill", rp);
panel2.add(redPill);
newFrame.add(panel2, BorderLayout.CENTER);
newFrame.setVisible(true);
}
private class TheHandler implements ItemListener, ActionListener{
public void itemStateChanged(ItemEvent IE) {
//listen for an item to be selected.
if(IE.getStateChange() == ItemEvent.SELECTED) {
Object selection = menu.getSelectedItem();
if("The Matrix".equals(selection)) {
matrixPanel();
}
else if("Another Option".equals(selection)) {
}
}
}
public void actionPerformed(ActionEvent AE) {
if(AE.getSource() == bluePill) {
newFrame.remove(panel);
newFrame.remove(panel2);
newFrame.repaint();
}
}
}
//MAIN
public static void main(String[] args) {
MultiForm go = new MultiForm();
go.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
go.setSize(400, 200);
go.setVisible(true);
}
}
Use a Card Layout. You can swap panels as required.
The tutorial has a working example.
You can use:
jpanel.removeAll();
Either to delete a certain JComponent by using the JComponent itself like:
JFrame frame = new JFrame();
JPanel panel = new JPanel();
frame.add(panel);
frame.remove(panel);
panel.getGraphics().clearRect(0, 0, panel.getWidth(), panel.getHeight());
Related
I'm using Netbeans 6.5.1 to create an application that involves transferring data between 2 frames, I mean the user will enter the data in the first frame and the data entered must be transferred to the second frame, without making the second frame visible. The second frame will not be visible initially and even after getting the data from the first frame it must not become visible till a certain button(from a different frame of the same project) is pressed. I tried overloading the constructor, but when I'm calling the method in frame-1 I'm unable to just store the data (and display it in a jLabel). I can only do this by using the setVisible() method as ( new Frame2(data_to_be_transferred).setVisible(true); ). This method does the job but it makes the second frame visible with the data. So how do I transfer the data between 2 frames without making the second frame visible?
You could either create your frame with the data Frame2 f2 = new Frame2(data_to_be_transferred); and then make it visible only when needed via f2.setVisible(true);
OR
keep your data to be transferred and only create the frame2 later on when really needed and make it immediately visible as you're already doing new Frame2(data_to_be_transferred).setVisible(true);
Cheers!
Example :
public class SomeClass extends JFrame {
JPanel panel;
JTextField textField;
JButton button;
JLabel label;
String data;
SomeClass() {
panel = new JPanel();
textField = new JTextField(16);
button = new JButton("Magic");
label = new JLabel();
panel.add(button);
panel.add(textField);
setContentPane(panel);
setSize(400,100);
setVisible(true);
}
public static void main(String[] args) {
new SomeClass();
}
button.addActionListener(e ->{
data = textField.getText();
if((data == null) || (data.equals(""))){
return;
}else {
this.remove(panel)
JPanel panel2 = new JPanel();
label = new JLabel();
panel.add(label);
this.setContentPane(panel2);
label.setText(data);
}
});
}
Sorry, I confused.. you can create new JFrame instance in actionPerformed or as I did in e-> which is lambda expression.
public class AnotherClass extends JFrame {
JPanel panel;
JLabel label;
AnotherClass() {
panel = new JPanel();
label = new JLabel();
panel.add(label);
setContentPane(panel);
setSize(400,100);
setVisible(true);
}
}
And then thought reference of AnotherClass ( frame 2 ) set value for label.
button.addActionListener(e ->{
data = textField.getText();
if((data == null) || (data.equals(""))){
return;
}else {
AnotherClass anotherClass = new AnotherClass();
anotherClass.label.setText(data);
}
});
I have a Swing application using Card Layout which basically changes the displayed panel depending on what the user selects from a drop-down menu.
One of my panels has a form. I would need for when the submit buton is pressed for all the inputs to be collected and the Panel to be switched to another one. (This second panel is defined in a separate class) I would also need for all the input to be somehow passed to a method in the new panel.
Any suggestions?
Dario
If you look at the <--s in the following code, each should solve each different question you have in your post. I figured you should know how to make a submit button, so I didn't include that. (Note: this is not running code, just suggestions);
public class MainPanel entends JPanel {
CardLayout layout = new CardLayout(); <-- card layout
JPanel panel = new JPanel(layout); <-- set layout to main panel
NewPanel newPanel = new NewPanel(); <-- you new panel
JPanel p1 = new JPanel(); <-- random panel
JTextField text = new JTextField() <-- text field in form
JButton button = new JButton();
JComboBox cbox = new JComboBox(new String[] {"newPanel", "p1"}); <-- hold panel names
public MainPanel(){
panel.add(newPanel, "newPanel"); <-- name associated with panel
panel.add(p1, "p1");
...
cbox.addAItemListener(new ItemListener(){
public void itemStateChnaged(ItemEvent e){
layout.show(panel, (string).getItem()); <-- show Panel from combobox
}
});
button.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
String txt = text.getText();
newPanel.printText(txt); <-- Using method from other class
}
});
}
}
public class NewPanel extends JPanel {
public void printText(String text){ <-- method from other class
System.out.println(text);
}
}
Hello I am writing a sort of Menu for an encryption program I am writing. I finished the core of it, and now i want to try to create a GUI for it. Here is the code for the first Menu:
package matrix_with_GUI;
import javax.swing.*;
import java.awt.event.* ;
import java.awt.* ;
public class Main_Menu extends JFrame implements ActionListener{
private JButton action1 = new JButton ("");
private JButton action2 = new JButton ("");
private JPanel pane = new JPanel();
private JLabel lbl;
public static void main(String[] args) {
Main_Menu main = new Main_Menu();
}
public Main_Menu(){
super();
JPanel pane=new JPanel();
setTitle ("Start Menu") ;
JFrame frame = new JFrame("");
setVisible(true);
setSize (380, 260) ;
setLocation (450, 200) ;
frame.setDefaultCloseOperation (JFrame.EXIT_ON_CLOSE) ;
action1 = new JButton("Start");
action2 = new JButton("Exit");
lbl = new JLabel ("Welcome to the Matrix Encoder/Decoder!!!");
setLayout(new FlowLayout());
add (lbl) ;
add(action1, BorderLayout.CENTER);
action1.addActionListener (this);
add(action2, BorderLayout.CENTER);
action2.addActionListener (this);
}
#Override
public void actionPerformed(ActionEvent event) {
// TODO Auto-generated method stub
OptionsMenu x = new OptionsMenu();
if (event.getSource() == action1)
{
System.exit(0);
x.OptionsMenu();
}
else if(event.getSource() == action2){
System.exit(0);
}
}
}
When the Start Button is clicked, the new menu comes up all fine and good, but the first menu stays open. Is there a way to close this first menu AND open the second menu with the first button click? I'm very new to GUI so the simplest solution would be very helpful. On a side note is there a simple way to move the Start button to the next line? Thanks
You have 2 options: you can use a Window Listener, or you can use the dispose() method. To do the dispose() just type
* This is better to be used with subframes and 2nd level windows.*
this.dispose();
or check this link for using the window listener
Closing JFrame
In order to close the Main_Menu, you can just call its dispose method:
this.dispose();
instead of calling System.exit(0), which will terminate the JVM altogether.
I'm trying to make a little game that will first show the player a simple login screen where they can enter their name (I will need it later to store their game state info), let them pick a difficulty level etc, and will only show the main game screen once the player has clicked the play button. I'd also like to allow the player to navigate to a (hopefully for them rather large) trophy collection, likewise in what will appear to them to be a new screen.
So far I have a main game window with a grid layout and a game in it that works (Yay for me!). Now I want to add the above functionality.
How do I go about doing this? I don't think I want to go the multiple JFrame route as I only want one icon visible in the taskbar at a time (or would setting their visibility to false effect the icon too?) Do I instead make and destroy layouts or panels or something like that?
What are my options? How can I control what content is being displayed? Especially given my newbie skills?
A simple modal dialog such as a JDialog should work well here. The main GUI which will likely be a JFrame can be invisible when the dialog is called, and then set to visible (assuming that the log-on was successful) once the dialog completes. If the dialog is modal, you'll know exactly when the user has closed the dialog as the code will continue right after the line where you call setVisible(true) on the dialog. Note that the GUI held by a JDialog can be every bit as complex and rich as that held by a JFrame.
Another option is to use one GUI/JFrame but swap views (JPanels) in the main GUI via a CardLayout. This could work quite well and is easy to implement. Check out the CardLayout tutorial for more.
Oh, and welcome to stackoverflow.com!
Here is an example of a Login Dialog as #HovercraftFullOfEels suggested.
Username: stackoverflow Password: stackoverflow
import java.awt.*;
import java.awt.event.*;
import java.util.Arrays;
import javax.swing.*;
public class TestFrame extends JFrame {
private PassWordDialog passDialog;
public TestFrame() {
passDialog = new PassWordDialog(this, true);
passDialog.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
JFrame frame = new TestFrame();
frame.getContentPane().setBackground(Color.BLACK);
frame.setTitle("Logged In");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLocationRelativeTo(null);
frame.setExtendedState(JFrame.MAXIMIZED_BOTH);
}
});
}
}
class PassWordDialog extends JDialog {
private final JLabel jlblUsername = new JLabel("Username");
private final JLabel jlblPassword = new JLabel("Password");
private final JTextField jtfUsername = new JTextField(15);
private final JPasswordField jpfPassword = new JPasswordField();
private final JButton jbtOk = new JButton("Login");
private final JButton jbtCancel = new JButton("Cancel");
private final JLabel jlblStatus = new JLabel(" ");
public PassWordDialog() {
this(null, true);
}
public PassWordDialog(final JFrame parent, boolean modal) {
super(parent, modal);
JPanel p3 = new JPanel(new GridLayout(2, 1));
p3.add(jlblUsername);
p3.add(jlblPassword);
JPanel p4 = new JPanel(new GridLayout(2, 1));
p4.add(jtfUsername);
p4.add(jpfPassword);
JPanel p1 = new JPanel();
p1.add(p3);
p1.add(p4);
JPanel p2 = new JPanel();
p2.add(jbtOk);
p2.add(jbtCancel);
JPanel p5 = new JPanel(new BorderLayout());
p5.add(p2, BorderLayout.CENTER);
p5.add(jlblStatus, BorderLayout.NORTH);
jlblStatus.setForeground(Color.RED);
jlblStatus.setHorizontalAlignment(SwingConstants.CENTER);
setLayout(new BorderLayout());
add(p1, BorderLayout.CENTER);
add(p5, BorderLayout.SOUTH);
pack();
setLocationRelativeTo(null);
setDefaultCloseOperation(DISPOSE_ON_CLOSE);
addWindowListener(new WindowAdapter() {
#Override
public void windowClosing(WindowEvent e) {
System.exit(0);
}
});
jbtOk.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
if (Arrays.equals("stackoverflow".toCharArray(), jpfPassword.getPassword())
&& "stackoverflow".equals(jtfUsername.getText())) {
parent.setVisible(true);
setVisible(false);
} else {
jlblStatus.setText("Invalid username or password");
}
}
});
jbtCancel.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
setVisible(false);
parent.dispose();
System.exit(0);
}
});
}
}
I suggest you insert the following code:
JFrame f = new JFrame();
JTextField text = new JTextField(15); //the 15 sets the size of the text field
JPanel p = new JPanel();
JButton b = new JButton("Login");
f.add(p); //so you can add more stuff to the JFrame
f.setSize(250,150);
f.setVisible(true);
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
Insert that when you want to add the stuff in. Next we will add all the stuff to the JPanel:
p.add(text);
p.add(b);
Now we add the ActionListeners to make the JButtons to work:
b.addActionListener(this);
public void actionPerforemed(ActionEvent e)
{
//Get the text of the JTextField
String TEXT = text.getText();
}
Don't forget to import the following if you haven't already:
import java.awt.event*;
import java.awt.*; //Just in case we need it
import java.x.swing.*;
I hope everything i said makes sense, because sometimes i don't (especially when I'm talking coding/Java) All the importing (if you didn't know) goes at the top of your code.
Instead of adding the game directly to JFrame, you can add your content to JPanel (let's call it GamePanel) and add this panel to the frame. Do the same thing for login screen: add all content to JPanel (LoginPanel) and add it to frame. When your game will start, you should do the following:
Add LoginPanel to frame
Get user input and load it's details
Add GamePanel and destroy LoginPanel (since it will be quite fast to re-create new one, so you don't need to keep it memory).
Ok so im working on this game in java called 8 bit chimera. Im working on the main menu right now but when im using the card layout the window wont open for some reason. Here is some code.
import javax.swing.*;
import java.awt.*;
public class MainScreen extends JFrame{
String Title = "MainMenu";
MainMenuComp MMC = new MainMenuComp();
BreedingGround BGR = new BreedingGround();
public MainScreen() {
setTitle("8-bit Chimera "+Title);
setSize(800,600);
setResizable(false);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setVisible(true);
add(MMC);
add(BGR);
}
public static void main(String[] args){
new MainScreen();
}
}
that was the Main window
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class MainMenuComp extends JPanel implements ActionListener{
BreedingGround BGR = new BreedingGround();
ImageData ID = new ImageData();
Image TitleBg;
Image Title;
CardLayout CL;
JButton Play;
public MainMenuComp() {
setLayout(new GridBagLayout());
GridBagConstraints GBC = new GridBagConstraints();
ImageIcon TitleData = new ImageIcon(ID.TitleSource);
ImageIcon TitleBackGroundData = new ImageIcon(ID.TitleBackGroundSource);
ImageIcon PlayData = new ImageIcon(ID.PlaySource);
TitleBg = TitleBackGroundData.getImage();
Title = TitleData.getImage();
Play = new JButton();
Play.setIcon(PlayData);
add(Play,GBC);
add(BGR,"Breed");
}
public void actionPerformed(ActionEvent AE){
if(AE.getSource() == Play){
CL.show(this, "Breed");
}
}
public void paintComponent(Graphics g){
g.drawImage(TitleBg,0,0,800,600,this);
g.drawImage(Title,250,80,280,140,this);
}
}
this was the card layout
import javax.swing.*;
import java.awt.*;
public class BreedingGround extends JPanel{
ImageData ID = new ImageData();
Image Swamp;
CardLayout CL;
public BreedingGround(){
setLayout(new GridBagLayout());
GridBagConstraints c = new GridBagConstraints();
ImageIcon SwampData = new ImageIcon(ID.SwampSource);
Swamp = SwampData.getImage();
}
public void paintComponent(Graphics g){
g.drawImage(Swamp,0,0,800,600,this);
}
}
and that was what i wanted the CardLayout to open. The problem is that when i try to run it the window wont run and this keeps showing in the compiler.
--------------------Configuration: 8-bit Chimera - JDK version 1.6.0_26 - --------------------
Exception in thread "main" java.lang.IllegalArgumentException: cannot add to layout: constraints must be a GridBagConstraint
at java.awt.GridBagLayout.addLayoutComponent(GridBagLayout.java:685)
at java.awt.Container.addImpl(Container.java:1074)
at java.awt.Container.add(Container.java:927)
at MainMenuComp.<init>(MainMenuComp.java:26)
at MainScreen.<init>(MainScreen.java:7)
at MainScreen.main(MainScreen.java:23)
Process completed.
All i really want to know is what this is saying.
I don't see where you ever set the layout of a container to be CardLayout, and if you don't set the layout to this, you can't magically use it. If you haven't yet gone through the CardLayout tutorial, consider doing so as it's all explained there.
Edit 1
Comment from Alexander Kim:
when i added the cardbagLayout it wont load the image and the button size filled the whole screen. I also took away the grids
You need to nest your JPanels in order to nest layouts. Use a single JPanel as the CardLayout container whose single function it is is to display other JPanels (the "cards"). These other JPanels will use whatever layouts that are necessary to properly display the components that they hold such as your JButton or "grids" (whatever they are). And even these JPanels may hold other JPanels that use other layouts.
Again, please read the layout tutorials as it's all described well there. You will not regret doing this.
Edit 2
Here's a very simple example that uses a CardLayout. The component displayed by the CardLayout using JPanel (called the cardContainer) is changed depending on which item is selected in a combobox.
Here's the CardLayout and the JPanel that uses it:
private CardLayout cardLayout = new CardLayout();
// *** JPanel to hold the "cards" and to use the CardLayout:
private JPanel cardContainer = new JPanel(cardLayout);
And here's how I add a component to the cardlayout-using JPanel:
JPanel redPanel = new JPanel();
//...
String red = "Red Panel";
cardContainer.add(redPanel, red); // add the JPanel to the container with the String
I also add the String to a JComboBox so I can use this combo box later to tell the CardLayout to display this JPanel (redPanel) if the user selects the item "Red" in this same JComboBox:
cardCombo.addItem(red); // also add the String to the JComboBox
Here's the ActionListener in the JComboBox that lets me change the item displayed in the cardlayout using JPanel:
cardCombo.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
String item = cardCombo.getSelectedItem().toString();
// *** if combo box changes it tells the CardLayout to
// *** swap views based on the item selected in the combo box:
cardLayout.show(cardContainer, item);
}
});
And here's the whole shebang:
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class SimpleCardLayoutDemo {
private CardLayout cardLayout = new CardLayout();
// *** JPanel to hold the "cards" and to use the CardLayout:
private JPanel cardContainer = new JPanel(cardLayout);
private JComboBox cardCombo = new JComboBox();
private JPanel comboPanel = new JPanel();;
public SimpleCardLayoutDemo() {
JPanel greenPanel = new JPanel(new BorderLayout());
greenPanel.setBackground(Color.green);
greenPanel.add(new JScrollPane(new JTextArea(10, 25)), BorderLayout.CENTER);
greenPanel.setBorder(BorderFactory.createEmptyBorder(15, 15, 15, 15));
greenPanel.add(new JButton("Bottom Button"), BorderLayout.PAGE_END);
String green = "Green Panel";
cardContainer.add(greenPanel, green);
cardCombo.addItem(green);
JPanel redPanel = new JPanel();
redPanel.setBackground(Color.red);
redPanel.add(new JButton("Foo"));
redPanel.setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5));
String red = "Red Panel";
cardContainer.add(redPanel, red);
cardCombo.addItem(red);
JPanel bluePanel = new JPanel();
bluePanel.setBackground(Color.blue);
JLabel label = new JLabel("Blue Panel", SwingConstants.CENTER);
label.setForeground(Color.white);
label.setFont(label.getFont().deriveFont(Font.BOLD, 32f));
bluePanel.add(label);
String blue = "Blue Panel";
cardContainer.add(bluePanel, blue);
cardCombo.addItem(blue);
comboPanel.add(cardCombo);
cardCombo.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
String item = cardCombo.getSelectedItem().toString();
// *** if combo box changes it tells the CardLayout to
// *** swap views based on the item selected in the combo box:
cardLayout.show(cardContainer, item);
}
});
}
public JPanel getCardContainerPanel() {
return cardContainer;
}
public Component getComboPanel() {
return comboPanel ;
}
private static void createAndShowUI() {
SimpleCardLayoutDemo simplecardDemo = new SimpleCardLayoutDemo();
JFrame frame = new JFrame("Simple CardLayout Demo");
frame.getContentPane().add(simplecardDemo.getCardContainerPanel(), BorderLayout.CENTER);
frame.getContentPane().add(simplecardDemo.getComboPanel(), BorderLayout.PAGE_END);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
// to run Swing in a thread-safe way
public static void main(String[] args) {
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
createAndShowUI();
}
});
}
}
Your problem is with add(BGR,"Breed");. The layout of MainMenuComp is a GridBagLayout, so the constraint must be a GridBagConstraint, not a String (you have "Breed" as the constraint).