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Setting font size for a print operation from a text component

I have the following program that puts a text string in a JTextArea and offers a print dialog for printing it:
public class PrintTest
{
private static String fontName = Font.MONOSPACED; // "Verdana"
private static FontUIResource defaultFixedWidthCellFont = new FontUIResource(fontName, Font.PLAIN, 16);
public static FontUIResource getDefaultCellFont() { return defaultFixedWidthCellFont; }
public static void main(String[] args)
{
JFrame frame = new JFrame("Print test");
JTextArea textArea = new JTextArea();
textArea.setEditable(false);
textArea.setFont(getDefaultCellFont());
textArea.setPreferredSize(new Dimension(400,200));
textArea.setText("one and two and three");
JScrollPane scrollPane = new JScrollPane(textArea);
frame.add(scrollPane);
frame.pack();
frame.setVisible(true);
try { textArea.print(); }
catch (PrinterException pe) { pe.printStackTrace(); }
}
}
In the real application, the text area does not need to be edited, it does need to be a fixed width font of this size. I am willing to use a text component other than a JTextArea, as long as I can set it to a fixed width font size and put it in a JScrollPane. I do not want any text wrapping. After getting put on the screen, it does not change (it's a report).
The problem is that the text, when printed on the printer, is too large. I do not want to reduce the size of the text in the window. I do not want to put the text in a file and print the file. The text is one long string in my Java program, there's no need to make a file of it.
When I attempt to search solutions, I get lots of articles about printing from eclipse, using System.out.println, and an occasional article that involves using Graphics objects to render individual text strings. I was hoping for something simpler; the program does do the printing, I just need a different font.
I have tried putting the text into another JTextArea and giving it a derived font with a different size, but that didn't work -- I did not render that text area, and don't know if that would matter. Is that a way to get this done? I've seen references to off-screen buffers for graphics, but don't know how I'd go about telling my text component to render itself to an offscreen buffer.
Or is there a better way to get this done?

Create a new JTextArea with the font you want and print that instead of the one on the screen
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Font;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.print.PrinterException;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.plaf.FontUIResource;
public class Main {
public static void main(String[] args) {
new Main();
}
public Main() {
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 static class TestPane extends JPanel {
private static String fontName = Font.MONOSPACED; // "Verdana"
private static FontUIResource defaultFixedWidthCellFont = new FontUIResource(fontName, Font.PLAIN, 32);
private static FontUIResource defaultFixedWidthPrintFont = new FontUIResource(fontName, Font.PLAIN, 8);
public static FontUIResource getDefaultCellFont() {
return defaultFixedWidthCellFont;
}
public static FontUIResource getDefaultPrintFont() {
return defaultFixedWidthPrintFont;
}
public TestPane() {
setLayout(new BorderLayout());
JTextArea textArea = new JTextArea();
textArea.setEditable(false);
textArea.setFont(getDefaultCellFont());
textArea.setText("one and two and three");
JScrollPane scrollPane = new JScrollPane(textArea);
add(scrollPane);
JButton print = new JButton("Print");
add(print, BorderLayout.SOUTH);
print.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
JTextArea printTA = new JTextArea(textArea.getText());
printTA.setFont(getDefaultPrintFont());
try {
printTA.print();
} catch (PrinterException pe) {
pe.printStackTrace();
}
}
});
}
#Override
public Dimension getPreferredSize() {
return new Dimension(400, 200);
}
}
}

JList position resets to default whenever update occurs

list is to accept input from Action1 this works, however, whenever a new element is added to the list, the list's position moves back to the default top-middle position.
This also occurs when the frame is resized, so as a temporary fix I the line frame.setResizable(false) but I do not want that to be permanent.
How would I fix both of these issues?
import static java.lang.String.*;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.awt.event.ActionListener;
public class lists
{
static String newUrl;
static DefaultListModel<String> model = new DefaultListModel<String>();
static int listXCoord = 650;
static int listYCoord = 10;
public static void createGUI()
{
JFrame frame = new JFrame();
frame.setVisible(true);
frame.setSize(800,600);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setResizable(false);
JPanel panel = new JPanel();
frame.add(panel);
JButton addurl = new JButton("Add URL");
panel.add(addurl);
addurl.addActionListener(new Action1());
JButton remurl = new JButton("Remove URL");
panel.add(remurl);
//model.addElement("one");
//model.addElement("two");
//model.addElement("three");
JList list = new JList<String>(model);
list.setCellRenderer(new DefaultListCellRenderer());
list.setVisible(true);
list.setLocation(listXCoord, listYCoord);
list.setBackground(new Color(186, 203, 250));
//list.setLocation(650, 10);
panel.add(list);
list.setSize(130, 540);
}
static class Action1 implements ActionListener
{
public void actionPerformed (ActionEvent e)
{
newUrl = JOptionPane.showInputDialog("Enter the URL to be Launched");
model.addElement(newUrl);
}
}
public static void main(String[] args)
{
createGUI();
}
}

Basically, you're fighting the layout manager (Flowlayout) and losing. When you add a new element to the JList, the container hierarchy is been revalidated which is causing the layout managers to re-layout the contents of their containers
The basic solution would be to use a different layout, but, JFrame uses a BorderLayout, so instead of adding the JList to the JPanel, you could simply add it to the EAST position of the frame instead
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.DefaultListCellRenderer;
import javax.swing.DefaultListModel;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JList;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class Lists {
static String newUrl;
static DefaultListModel<String> model = new DefaultListModel<String>();
static int listXCoord = 650;
static int listYCoord = 10;
public static void createGUI() {
JFrame frame = new JFrame();
frame.setSize(800, 600);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel panel = new JPanel();
frame.add(panel);
JButton addurl = new JButton("Add URL");
panel.add(addurl);
addurl.addActionListener(new Action1());
JButton remurl = new JButton("Remove URL");
panel.add(remurl);
//model.addElement("one");
//model.addElement("two");
//model.addElement("three");
JList list = new JList<String>(model);
list.setCellRenderer(new DefaultListCellRenderer());
list.setVisible(true);
list.setLocation(listXCoord, listYCoord);
list.setBackground(new Color(186, 203, 250));
//list.setLocation(650, 10);
frame.add(new JScrollPane(list), BorderLayout.EAST);
frame.setVisible(true);
}
static class Action1 implements ActionListener {
public void actionPerformed(ActionEvent e) {
newUrl = JOptionPane.showInputDialog("Enter the URL to be Launched");
model.addElement(newUrl);
}
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
ex.printStackTrace();
}
createGUI();
}
});
}
}
See Laying Out Components Within a Container, How to Use BorderLayout and How to use FlowLayout for more details.
You should also be calling setVisible last, after all the components have been added to the frame, this reduces the possibilities that some of your components won't be displayed when you think they should be.
JList will also benefit from been contained within a JScrollPane. See How to Use Lists and How to Use Scroll Panes for more details

How can I switch focus to a canvas?

I have this class and I want to switch focus to the Game class right after it was invoked. I might've not understand the purpose of focus but when I press start I have to click on the game canvas itself so I can use the keyboard . In other words: How can I make it so I don't have to click on it to use the keyboard?
package com.runner.panels;
import java.awt.CardLayout;
import java.awt.Color;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JPanel;
import com.runner.main.Game;
import com.runner.main.Main;
public class PlayPanel extends JPanel{
private static final long serialVersionUID = 1L;
public PlayPanel(){
//setting the layout of the playpanel to null
setLayout(null);
//setting up the info panel : high score, meters ran, pause button etc...
JPanel info = new JPanel();
info.setBounds(0,0,1200,50);
add(info);
//back button
JButton back = new JButton("Back");
info.add(back);
Game game = new Game();
game.setBounds(0,50,1200,521);
game.setBackground(Color.black);
add(game);
back.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e) {
CardLayout cl = (CardLayout) Main.mainp.getLayout();
cl.show(Main.mainp, "Menu");
}
});
}
}

Off topic: (kinda)
The fact that you are doing Main.mainp.getLayout();, calling the panel statically tells me you have poor design and should be looking into other options like an Model-view-controller pattern, an Observer pattern, or at the very least passing a reference of of the Main to the panel, instead of using static objects/calls.
Back on topic
Sounds like a common KeyListener problem. Generally to gain focus you call requestFocusInWindow(). But you still have to worry about other components stealing the focus way after the fact.
I would instead recommend using Key Bindings instead of KeyListener. You have more control over the focus. For instance, by using
InputMap im = panel.getInputMap(JComponent.WHEN_IN_FOCUSED_WINDOW);
im.put(KeyStroke.getKeyStroke("SPACE"), "hitSpace");
panel.getActionMap().put("hitSpace", new AbstractAction(){
public void actionPerformed(ActionEvent e) {
// do something.
}
});
The panel will have immediate access to the action once you show it from the CardLayout. If you happen to use any other components that would steal the focus away from the panel, the action is still accessible because of the WHEN_IN_FOCUSED_WINDOW input map
Here's a simple example. Type A if it is on panel A, you will see it print. If you type B, it won't print because panel A is in the window. Also if you try and press the button in the panel to steal the focus, you can still type and it will still print. Same goes for panel B
import java.awt.BorderLayout;
import java.awt.CardLayout;
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.AbstractAction;
import javax.swing.InputMap;
import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.KeyStroke;
import javax.swing.SwingUtilities;
public class Main {
CardLayout layout = new CardLayout();
JPanel panel = new JPanel(layout);
JPanel p1 = new JPanel() {
#Override
public Dimension getPreferredSize() {
return new Dimension(300, 300);
}
};
JPanel p2 = new JPanel() {
#Override
public Dimension getPreferredSize() {
return new Dimension(300, 300);
}
};
JButton b1 = new JButton("panelA");
JButton b2 = new JButton("panelB");
public Main() {
addKeyBind(p1, "pressA", "A");
addKeyBind(p2, "pressB", "B");
p1.add(new JButton("Button for Panel A"));
p2.add(new JButton("Button for Panel B"));
panel.add(p1, "panelA");
panel.add(p2, "panelB");
b1.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e) {
show("panelA");
}
});
b2.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e) {
show("panelB");
}
});
JPanel buttonPanel = new JPanel();
buttonPanel.add(b1);
buttonPanel.add(b2);
JFrame frame = new JFrame();
frame.add(panel);
frame.add(buttonPanel, BorderLayout.PAGE_END);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public void show(String panelName) {
layout.show(panel, panelName);
}
private void addKeyBind(JComponent comp, String name, final String stroke) {
InputMap im = comp.getInputMap(JComponent.WHEN_IN_FOCUSED_WINDOW);
im.put(KeyStroke.getKeyStroke(stroke), name);
comp.getActionMap().put(name, new AbstractAction(){
public void actionPerformed(ActionEvent e) {
System.out.println(stroke + " pressed");
}
});
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable(){
public void run() {
new Main();
}
});
}
}
Take some time to go over the link I gave you for Key Bindings to learn more.
Back off-topic
Take a look at #AndrewThompson's comment about the null layouts. Learn how to use the LayoutManagers

I believe your problem would be fixed if you add
setFocusable(true);
to your PlayPanel constructor (works for me).
Also, if you want a specific Panel in your GUI to have focus when you start your application, follow the link in the comment of "user3218114", as this will explain how to implement this functionality with Listeners.
Good luck!

You don't need to do anything. The container should be focusable for that.
Here is a code to demonstrate.
package one;
import java.awt.Canvas;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.event.FocusEvent;
import java.awt.event.FocusListener;
import javax.swing.JFrame;
public class PlayPanel extends Canvas {
public static void main(String... args) {
PlayPanel p = new PlayPanel();
p.addFocusListener(new FocusListener() {
#Override
public void focusGained(FocusEvent e) {
p.msg = "Focus gained";
p.repaint();
}
#Override
public void focusLost(FocusEvent e) {
p.msg = "Focus Lost";
p.repaint();
}
});
p.setBackground(Color.GRAY);
JFrame f = new JFrame();
f.add(p);
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.setSize(300, 200);
f.setLocation(300, 300);
f.setVisible(true);
}
String msg = "NO FOCUS";
public void paint(Graphics g) {
g.drawString(msg, 50, 50);
}
}

Adding Text In a New Window

I'm in a bit of a situation here.I'm making a new program, when you click on the menu bar it opens a new window for the Licence, now here is the problem, how would I add text into that new window, here is my code for the new window:
JFrame frame = new JFrame("Licence");
frame.setSize(500,120);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
I know this is a easy question, I just can't think of the correct code for it.

You can try something like
JDialog dialog = new JDialog(your_frame_reference, "Licence");
dialog .setModal(true);
dialog .setLocationRelativeTo(null);
dialog. getContentPane().add(new JLabel(your_text);
dialog .setVisible(true);

You can use label
JFrame frame = new JFrame("Licence");
JLabel label = new JLabel("Text-Only Label");
label.setFont(new Font("Serif", Font.PLAIN, 36));
frame.add(label);

You can add text by creating JLabels like so:
JLabel label = new JLabel("Hello World");
This can then be added to your JFrame.

Try this Example
import java.awt.BorderLayout;
import java.awt.Window;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
public class TestDialog {
protected static void initUI() {
JPanel pane = newPane("Label in frame");
JFrame frame = new JFrame("Title");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(pane);
frame.pack();
frame.setVisible(true);
}
public static JPanel newPane(String labelText) {
JPanel pane = new JPanel(new BorderLayout());
pane.add(newLabel(labelText));
pane.add(newButton("Open dialog"), BorderLayout.SOUTH);
return pane;
}
private static JButton newButton(String label) {
final JButton button = new JButton(label);
button.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
Window parentWindow = SwingUtilities.windowForComponent(button);
JDialog dialog = new JDialog(parentWindow);
dialog.setLocationRelativeTo(button);
dialog.setModal(true);
dialog.add(newPane("Label in dialog"));
dialog.pack();
dialog.setVisible(true);
}
});
return button;
}
private static JLabel newLabel(String label) {
JLabel l = new JLabel(label);
l.setFont(l.getFont().deriveFont(24.0f));
return l;
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
initUI();
}
});
}
}

How to update JTextFields in a GridLayout?

I have a MainPanel which uses the Gridlayout. Consequently I have created four JPanel classes for the: NORTH, EAST, CENTER and EAST layouts respectively. I then add all four to my MainPanel.
However, on my WEST panel I use another grid layout to store JButtons and JTextFields. I want to constantly update my JTextFields as they display a value (that changes when a button on another panel is clicked). How do I allow that value to be changed when the JFrame is running?
I tried using paintComponent, but it keeps on adding multiple copies of the same JTextField after each other, as I add it in my paintComponent method. If I remove the add method the values won't update.

Action works well to encapsulate such functionality. In the example below, a number of text fields listen for an ActionEvent received from a single Update button. The common UpdateHandler is derived from AbstractAction.
import java.awt.BorderLayout;
import java.awt.EventQueue;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;
import javax.swing.AbstractAction;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTextField;
/** #see http://stackoverflow.com/a/14947144/230513 */
public class Test {
private JButton button = new JButton("Update");
private void display() {
JFrame f = new JFrame("Test");
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.add(createPanel(button), BorderLayout.NORTH);
f.add(createPanel(button), BorderLayout.WEST);
f.add(createPanel(button), BorderLayout.EAST);
f.add(createPanel(button), BorderLayout.SOUTH);
JPanel p = new JPanel();
p.add(button);
f.add(p, BorderLayout.CENTER);
f.getRootPane().setDefaultButton(button);
f.pack();
f.setLocationRelativeTo(null);
f.setVisible(true);
}
private static JPanel createPanel(JButton b) {
JPanel panel = new JPanel(new FlowLayout(FlowLayout.CENTER));
final JTextField text = new JTextField();
b.addActionListener(new UpdateHandler(text));
panel.add(text);
return panel;
}
private static class UpdateHandler extends AbstractAction {
private JTextField text;
private DateFormat df = new SimpleDateFormat("HH:mm:ss.SSS");
public UpdateHandler(JTextField t) {
super("update");
t.setText(df.format(new Date()));
this.text = t;
}
#Override
public void actionPerformed(ActionEvent e) {
text.setText(df.format(new Date()));
}
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
new Test().display();
}
});
}
}