I have a text game which has buttons. When a button is clicked, text appears. My text appears inside a jPanel, which is inside a jScrollPane. I would like my jPanel to automatically make more vertical space for my lines of text to be added. I have been doing it by hand but it is a lot more time consuming. Is there anyway to do this, or maybe pack a jPanel somehow. I am pretty new to this so if any extra information is needed for you to help me out feel free to ask. Thanks.
I would use a component that can do this automatically -- a JTextArea. It will automatically enlarge as more text is added.
If you need more specific help or a code example, please post your own small compilable and runnable test example program, and I can try to modify it.
You state:
I don't want to use a JTextArea because I don't want the user to be able to highlight or delete any of the text that was there in the first place.
No problem. Just make the JTextArea non-focusable and non-editable.
I have been using jLabels which are equal to "" and when a button is pressed, that jLabel is given a new value.
Try something like this:
import java.awt.event.ActionEvent;
import java.awt.event.KeyEvent;
import javax.swing.*;
#SuppressWarnings("serial")
public class AddNewLines extends JPanel {
private JTextArea textArea = new JTextArea(10, 15);
private JButton addLineBtn = new JButton(new AddLineAction("Add Line", KeyEvent.VK_A));
public AddNewLines() {
textArea.setEditable(false);
textArea.setFocusable(false);
textArea.setWrapStyleWord(true);
textArea.setLineWrap(true);
textArea.setOpaque(false);
JScrollPane scrollPane = new JScrollPane(textArea);
scrollPane.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
add(scrollPane);
add(addLineBtn);
}
class AddLineAction extends AbstractAction {
private int count = 0;
public AddLineAction(String name, int mnemonic) {
super(name);
putValue(MNEMONIC_KEY, mnemonic);
}
#Override
public void actionPerformed(ActionEvent e) {
if (count != 0) {
textArea.append("\n");
}
textArea.append("Line of Text: " + count);
count++;
}
}
private static void createAndShowGui() {
AddNewLines mainPanel = new AddNewLines();
JFrame frame = new JFrame("Add New Lines");
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
frame.getContentPane().add(mainPanel);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
Related
I am currently working on my school project to practice vocabulary, I have a method in my GUI that creates new vocabulary and the name of the list, I wanted to create a button that adds more Panels with input fields just this prototype image.
My idea is that when the user clicks
AddMoreButton it will add one JPanel just like P Panel, then the user can write vocabulary to send it to my database, is it possible to create something that?, I tried looping the P panel but it did not not change, any help would be appreciated.
private JPanel SetUpCreate() {
JPanel createPanel = new JPanel();
nameListInput = new JTextField(INPUT_FIELD_WIDTH);
termInput = new JTextField(INPUT_FIELD_WIDTH);
defintionInput = new JTextField(INPUT_FIELD_WIDTH);
p = new JPanel();
doneCreate = new JButton("Done");
doneCreate.addActionListener(new DoneCreateButtonAction());
addMoreButton = new JButton("Add");
addMoreButton.addActionListener(new AddMorePanelsListener());
p.setBorder(new BevelBorder(BevelBorder.RAISED));
p.add(termInput);
p.add(defintionInput);
JScrollPane pane = new JScrollPane(p);
createPanel.add(nameListInput);
createPanel.add(p);
createPanel.add(pane);
createPanel.add(doneCreate);
return createPanel;
}
private class DoneCreateButtonAction implements ActionListener {
public DoneCreateButtonAction() {
super();
}
public void actionPerformed(ActionEvent e) {
String namelist = nameListInput.getText();
String termglosa = termInput.getText();
String defintionglosa = defintionInput.getText();
try {
if (model.createWordList(namelist) && (model.createGlosa(termglosa, defintionglosa))) {
cl.show(cardPanel, "home");
}
} catch (IOException e1) {
JOptionPane.showMessageDialog(frame, "skapelsen av listan fungerar ej.");
}
}
}
private class AddMoreButtonAction implements ActionListener {
public AddMoreButtonAction() {
super();
}
public void actionPerformed(ActionEvent e) {
}
}
What I understand from your question is that you want to add another panel every time the user clicks the Add button and the panel to add contains fields for entering a word and its definition.
I see JScrollPane appears in the code you posted in your question. I think this is the correct implementation. In the below code, every time the user clicks the Add button I create a panel that contains the fields for a single word definition. This newly created panel is added to an existing panel that uses GridLayout with one column. Hence every time a new word definition panel is added, it is placed directly below the last word panel that was added and this GridLayout panel is placed inside a JScrollPane. Hence every time a word definition panel is added, the GridLayout panel height increases and the JScrollPane adjusts accordingly.
import java.awt.BorderLayout;
import java.awt.EventQueue;
import java.awt.GridLayout;
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.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextField;
import javax.swing.WindowConstants;
public class MorPanel implements ActionListener, Runnable {
private static final String ADD = "Add";
private JFrame frame;
private JPanel vocabularyPanel;
#Override
public void run() {
showGui();
}
#Override
public void actionPerformed(ActionEvent actionEvent) {
String actionCommand = actionEvent.getActionCommand();
switch (actionCommand) {
case ADD:
vocabularyPanel.add(createWordPanel());
vocabularyPanel.revalidate();
vocabularyPanel.repaint();
break;
default:
JOptionPane.showMessageDialog(frame,
actionCommand,
"Unhandled",
JOptionPane.ERROR_MESSAGE);
}
}
public JButton createButton(String text) {
JButton button = new JButton(text);
button.addActionListener(this);
return button;
}
public JPanel createButtonsPanel() {
JPanel buttonsPanel = new JPanel();
buttonsPanel.add(createButton(ADD));
return buttonsPanel;
}
private JScrollPane createMainPanel() {
vocabularyPanel = new JPanel(new GridLayout(0, 1));
vocabularyPanel.add(createWordPanel());
JScrollPane scrollPane = new JScrollPane(vocabularyPanel);
return scrollPane;
}
private JPanel createWordPanel() {
JPanel wordPanel = new JPanel();
JLabel wordLabel = new JLabel("Enter Term");
JTextField wordTextField = new JTextField(10);
JLabel definitionLabel = new JLabel("Enter Term Definition");
JTextField definitionTextField = new JTextField(10);
wordPanel.add(wordLabel);
wordPanel.add(wordTextField);
wordPanel.add(definitionLabel);
wordPanel.add(definitionTextField);
return wordPanel;
}
private void showGui() {
frame = new JFrame("Vocabulary");
frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
frame.add(createMainPanel(), BorderLayout.CENTER);
frame.add(createButtonsPanel(), BorderLayout.PAGE_END);
frame.setSize(480, 200);
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String[] args) {
EventQueue.invokeLater(new MorPanel());
}
}
As your code is not an Minimal Reproducible Example, I cannot provide further assistance than this:
Red part: Your main JPanel with BoxLayout
Green part: another JPanel with your JTextField in it.
Purple part: JScrollPane
Blue parts: custom JPanels with 2 panes in them, one on top for the number, one on the bottom for both JTextFields and icon, so I would say GridBagLayout or BoxLayout + FlowLayout
Orange part: JPanel with GridBagLayout or FlowLayout
Each time you clic on the + icon, you just create a new instance of the custom blue JPanel and that's it.
I have recently started working with Java+Swing building an UI and I currently have an issue with JTextField placed on JPanel with FlowLayout.
In my example I have a window, containing panel with button. Clicking the button adds a component derived from JPanel and containing JTextField.
The problem is that when I type in JTextField it does not get updated (does not get resized). However when I resize the window or do anything else which forces window/panel redraw, the text field being resized (just what I expect to happen automatically).
When I change base class from JPanel to JTextField it works in the way I try to achieve, but I need to have JPanel as the base class so that I can take advantages of putting child components to it.
I have checked different questions here as well as I have Googled trying to find the solution, however it did not work for me. I have tried validate/invalidate/revalidate/repaint in different combinations and for different components, as well as trying to enforce revalidation for each typed character, which does not sound as the right way for me. So far I understoon that it is something to do with Layout Managers.
Could anyone please help me with understanding how that works and what should I read about how Swing UI, layout management and redrawing is working?
Also, I would be glad if someone could help me with my particular issue with my code.
Thanks in advance!
Here is my code below:
import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
class TagVisual extends JPanel /*JTextField*/ {
private JTextField editField;
public TagVisual() {
FlowLayout layout = new FlowLayout();
layout.setHgap(0);
layout.setVgap(0);
setLayout(layout);
editField = new JTextField();
editField.setBackground(Color.RED);
editField.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
editField.setSize(editField.getSize());
editField.revalidate();
remove(editField);
add(editField);
revalidate();
repaint();
}
});
add(editField, FlowLayout.LEFT);
}
public void place(JPanel panel) {
panel.add(this);
editField.grabFocus();
}
}
public class MainWindow {
private JPanel mainPanel;
private JButton btnPlace;
private JFrame frame;
public MainWindow(JFrame frame) {
mainPanel = new JPanel(new FlowLayout());
btnPlace = new JButton();
btnPlace.setText("Place");
mainPanel.add(btnPlace);
this.frame = frame;
btnPlace.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
TagVisual v = new TagVisual();
v.place(mainPanel);
mainPanel.revalidate();
mainPanel.repaint();
mainPanel.updateUI();
frame.revalidate();
frame.repaint();
}
});
}
public static void main(String[] args) {
JFrame frame = new JFrame("TextFieldUpdateIssue");
frame.setContentPane(new MainWindow(frame).mainPanel);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setVisible(true);
}
}
If i were you, i would not try to resize the textfields when the user enters some text.
I suggest you to give them a fixed size using JTextField (int columns) constructor, this will allow you to create some textfields which are "wide enough".
If you still want to make them wider when some text is entered, you can't use an ActionListener, since it will fire an event when the user presses ENTER key, not based on the text entered.
For this purpose you can register a Document Listener on your textfield's document.
You also could override getPreferredSize () method to calculate and return an appropriate size. In the example below i use a JLabel for convenience to calculate the preferred width, but you could use FontMetrics.
If you are adding multiple tags to your panel, you should also consider using a JScrollPane in order to make scrollbars appear when your panel needs more space.
See this example (i changed a bit your code because it would not compile and the general design was bad, now i think it is better, but not still good) :
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
public class MainWindow
{
public static void main (String [] a) {
SwingUtilities.invokeLater (new Runnable () {
#Override public void run () {
try {
UIManager.setLookAndFeel (UIManager.getSystemLookAndFeelClassName ());
createAndShowGUI ();
}
catch (Exception e) {
JOptionPane.showMessageDialog (null, "An unexpected error occurred: " + e.getClass ().getSimpleName (), "Error", JOptionPane.ERROR_MESSAGE);
}
}
});
}
private static void createAndShowGUI () {
JFrame frame = new JFrame ("TextFieldUpdateIssue");
frame.setDefaultCloseOperation (JFrame.EXIT_ON_CLOSE);
frame.setContentPane (new MainPanel ());
frame.setExtendedState (JFrame.MAXIMIZED_BOTH);
frame.setLocationRelativeTo (null);
frame.setVisible (true);
}
}
class MainPanel extends JPanel
{
private JPanel tagsPanel;
public MainPanel () {
super (new BorderLayout (0, 10));
add (new JButton (new AbstractAction ("Add tag") {
#Override public void actionPerformed(ActionEvent e) {
addNewTag ();
}
}), BorderLayout.NORTH);
tagsPanel = new JPanel ();
tagsPanel.setLayout (new FlowLayout (FlowLayout.CENTER, 10, 0));
add (tagsPanel, BorderLayout.CENTER);
}
private void addNewTag () {
TagVisual v = new TagVisual ();
tagsPanel.add (v);
v.grabFocusOnField ();
revalidate ();
}
}
class TagVisual extends JPanel
{
private JTextField editField;
public TagVisual() {
super (new FlowLayout (FlowLayout.CENTER, 0, 0));
add (editField = createNewTextField (null), FlowLayout.LEFT);
}
private JTextField createNewTextField (String text) {
JTextField textField = new JTextField (text) {
#Override public Dimension getPreferredSize () {
Dimension d = super.getPreferredSize ();
return new Dimension (new JLabel (getText ()).getPreferredSize ().width + 10, d.height);
}
};
textField.setBackground (Color.RED);
textField.getDocument ().addDocumentListener (new DocumentListener () {
#Override public void changedUpdate (DocumentEvent e) {
revalidate ();
}
#Override public void insertUpdate (DocumentEvent e) {
revalidate ();
}
#Override public void removeUpdate (DocumentEvent e) {
revalidate ();
}
});
return textField;
}
public void grabFocusOnField () {
editField.grabFocus ();
editField.setCaretPosition (editField.getText ().length ());
}
}
Screenshot (short text):
Screenshot (Longer text):
Please review the code and note comments:
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTextField;
public class MainWindow {
private JPanel mainPanel;
private JButton btnPlace;
public MainWindow(){
JFrame frame = new JFrame("TextFieldUpdateIssue");
//you can't use components before initializing them
btnPlace = new JButton("Button");
frame.add(btnPlace, BorderLayout.NORTH);
mainPanel = new JPanel();
frame.add(mainPanel, BorderLayout.CENTER);
btnPlace.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
TagVisual v = new TagVisual();
mainPanel.add(v); //add it to main panel
//v.place(mainPanel);
//mainPanel.revalidate();
//mainPanel.repaint();
//mainPanel.updateUI();
//frame.revalidate();
//frame.repaint();
frame.pack();
}
});
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setVisible(true);
}
public static void main(String[] args) {
new MainWindow();
}
}
class TagVisual extends JPanel /*JTextField*/ {
private JTextField editField;
public TagVisual() {
FlowLayout layout = new FlowLayout();
layout.setHgap(0);
layout.setVgap(0);
setLayout(layout);
editField = new JTextField();
//give it a preferred size to be used by layout manager
editField.setPreferredSize(new Dimension(150,25));
editField.setBackground(Color.RED);
editField.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
//not sure what you want to do here
//not relevant to the question
}
});
add(editField, FlowLayout.LEFT);
}
}
I would like to make a gui where after i click a button i can paste a text with a lot of lines and submit that text.
Example of the code i have for create the button:
public class SimpleGui implements ActionListener {
JButton button;
SimpleGui g;
public static void main (String[] args) {
SimpleGui g = new SimpleGui();
g.go();
}
public void go(){
JFrame frame = new JFrame();
button = new JButton("Insert Player");
frame.getContentPane().add(button);
button.addActionListener(this);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(300, 300);
frame.setVisible(true);
}
#Override
public void actionPerformed(ActionEvent e) {
button.setText("Now paste the data! ");
}
}
Now where i have button.setText("Now paste the data! ");, what i want is to:
Create some kind of widget that allow me to insert 20 lines of text i've copied from a .txt document.
2) receive and manage the data that the user did put on the widget.
Can you help me?
Though your question is unclear but probably you're asking about a component where you can set your text. Use JTextArea as follows:
JTextArea textarea = new JTextArea("The initial text");
your_container.add(textarea);
Then whenever you want to get the text from your text area, use:
String data = textarea.getText();
If at runtime you want to set the textarea to some data you can:
textarea.setText("Your data here");
EDIT :
After the OP added the code, I think this is what he wants to achieve:
import javax.swing.*;
import java.awt.event.*;
import java.awt.*;
class SimpleGui implements ActionListener
{
JButton button;
SimpleGui g;
JTextArea textarea;
JFrame frame;
String data;
public static void main (String[] args)
{
SimpleGui g = new SimpleGui();
g.go();
}
public void go()
{
frame = new JFrame();
button = new JButton("Insert Player");
textarea = new JTextArea("Paste data here!");
frame.setLayout(new BorderLayout());
frame.getContentPane().add(button, BorderLayout.SOUTH);
button.addActionListener(this);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(300, 300);
frame.setVisible(true);
}
#Override
public void actionPerformed(ActionEvent e)
{
if(e.getActionCommand().equals("Insert Player"))
{
button.setText("Now paste the data!");
frame.getContentPane().add(textarea, BorderLayout.CENTER);
}
else if(e.getActionCommand().equals("Now paste the data!"))
{
data = textarea.getText();
System.out.println(data);
}
}
}
Your text data is in the data variable. You can use it as you like. I've simply demonstrated that by printing it.
How can i remove lines from a JTextArea one by one instead of all together?
I have a JTextArea which gets appended with string results from a thread, now i would like to remove one line at a time while the thread is executing.
You first need to decide what should trigger the line removal.
Should it be the addition of a new line, so that total line number is constant. If so then you should write your code to call the line removal code in the same location that where a new line is added.
Or should it be at a constant rate -- and if so, then you will want to use a Swing Timer for this.
Then you need to decide which line to remove. If not the first line, then you'll need to figure out how to calculate which line. The javax.swing.text.Utilities class can help you find out the start and finish location of every line of text in your JTextArea.
Edit
You ask:
the main concern is about how to remove it from the JTextArea, i have already calculated the start and end positions of a line that has to be deleted.But what function can assist in removing just that one line?
You would first get the JTextArea's Document by calling, getDocument()
Then you could call remove(int offs, int length) on the Document as per the Document API.
Try This :
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
class SwingControlDemo {
String [] m;
int i=0;
String append="";
private JFrame mainFrame;
private JLabel headerLabel;
private JLabel statusLabel;
private JPanel controlPanel;
Timer t;
public SwingControlDemo(){
prepareGUI();
}
public static void main(String[] args){
SwingControlDemo swingControlDemo = new SwingControlDemo();
swingControlDemo.showTextAreaDemo();
}
private void prepareGUI(){
mainFrame = new JFrame("Java Swing Examples");
mainFrame.setSize(400,400);
mainFrame.setLayout(new GridLayout(3, 1));
mainFrame.addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent windowEvent){
System.exit(0);
}
});
headerLabel = new JLabel("", JLabel.CENTER);
statusLabel = new JLabel("",JLabel.CENTER);
statusLabel.setSize(350,100);
controlPanel = new JPanel();
controlPanel.setLayout(new FlowLayout());
mainFrame.add(headerLabel);
mainFrame.add(controlPanel);
mainFrame.add(statusLabel);
mainFrame.setVisible(true);
}
private void showTextAreaDemo(){
headerLabel.setText("Control in action: JTextArea");
JLabel commentlabel= new JLabel("Comments: ", JLabel.RIGHT);
final JTextArea commentTextArea =
new JTextArea("This is a Swing tutorial "
+"\n to make GUI application in Java."+"\n to make GUI application in Java"+"\n to make GUI application in Java",5,20);
JScrollPane scrollPane = new JScrollPane(commentTextArea);
JButton showButton = new JButton("Show");
showButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
String s=commentTextArea.getText();
m=s.split("\n");
t.start();
}
});
t=new Timer(1000,new ActionListener(){
public void actionPerformed(ActionEvent e)
{
i++;
append="";
if(i<=m.length)
{
for(int j=i;j<m.length;j++)
{
append=append+m[j];
}
commentTextArea.setText(append);
}
else
{
t.stop();
}
}});
controlPanel.add(commentlabel);
controlPanel.add(scrollPane);
controlPanel.add(showButton);
mainFrame.setVisible(true);
}
}
I have created a frame in Java which has some textfields and buttons in it. Assuming that user wants more textfields (for example to add more data), I want to put a button and when a user clicks the button, then a new textfield should appear. then user can fill data in it and again by clicking that button another textfield should appear.
How can I do this ? What code I need to write for the button to show more and more text fields by clicking button?
Thank you !
It would be wise that instead of adding components to your JFrame directly, you add them to a JPanel. Though related to your problem, have a look at this small example, hopefully might be able to give you some hint, else ask me what is out of bounds.
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class JFrameExample
{
private JFrame frame;
private JButton button;
private JTextField tfield;
private String nameTField;
private int count;
public JFrameExample()
{
nameTField = "tField";
count = 0;
}
private void displayGUI()
{
frame = new JFrame("JFrame Example");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new GridLayout(0, 1, 2, 2));
button = new JButton("Add JTextField");
button.addActionListener(new ActionListener()
{
#Override
public void actionPerformed(ActionEvent ae)
{
tfield = new JTextField();
tfield.setName(nameTField + count);
count++;
frame.add(tfield);
frame.revalidate(); // For JDK 1.7 or above.
//frame.getContentPane().revalidate(); // For JDK 1.6 or below.
frame.repaint();
}
});
frame.add(button);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String... args)
{
SwingUtilities.invokeLater(new Runnable()
{
#Override
public void run()
{
new JFrameExample().displayGUI();
}
});
}
}
Supposing that you have a main container called panel and a button variable button which is already added to panel, you can do:
// handle the button action event
button.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
// create the new text field
JTextField newTextField = new JTextField();
// add it to the container
panel.add(newTextField);
panel.validate();
panel.repaint();
}
});
When adding the new text field, you may need to mention some layout related characteristics, depending on the layout manager you are using (for instance if you use GridBagLayout, you will need to specify the constraints).