How to fit a long String into a JLabel - java

as the title says: I need to fit a JLabel into a JFrame, but the text in the JLabel are too long, so I need to add some linebreaks. The text in the JLabel are obtained from an online XML file, so i cant just change the text to contain linebreaks.
This code extracts data from the XML-file
Element element = (Element)nodes1.item(i);
String vær = getElementValue(element,"body");
String v = vær.replaceAll("<.*>", "" );
String forecast = "Vær: " + v;
in this case the string I want to add some linebreaks to the string v. The String v contains the parsed data from the xml file. The String forecast is returned and set as a text to the JLabel.
Just ask if something is uncleared, thanks in advance!

I suggest using a JTextArea instead and turning wrapping on. The only way to do it in a JLabel is to put line breaks <br />, which wouldn't work (at least not easily) in your situation if you don't know the text beforehand.
JTextArea is much more flexible. By default it looks different, but you can fiddle around with some of the display properties to make it look like a JLabel.
A simple modified usage example taken from the How to Use Text Areas tutorial -
public class JTextAreaDemo {
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
createAndShowGUI();
}
});
}
private static void createAndShowGUI(){
final JFrame frame = new JFrame("JTextArea Demo");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
final JPanel panel = new JPanel();
JTextArea textArea = new JTextArea(
"If there is anything the nonconformist hates worse " +
"than a conformist, it's another nonconformist who " +
"doesn't conform to the prevailing standard of nonconformity.",
6,
20);
textArea.setFont(new Font("Serif", Font.ITALIC, 16));
textArea.setLineWrap(true);
textArea.setWrapStyleWord(true);
textArea.setOpaque(false);
textArea.setEditable(false);
panel.add(textArea);
frame.add(panel);
frame.pack();
frame.setVisible(true);
}
}

JLabel is able to display HTML text, i.e. if you wrap your text with <html>your text<html> it might be able to wrap the text. That's not tested though, so YMMV.

you can dynamically tell your JLabel to resize itself to fit the text.
if you are not using a LayoutManager try :
jLabel.setText ("A somewaht long message I would not want to
stop");
jLabel.setSize(jLabel.getPreferredSize());
If you are using a Layout Manager this snippet should work:
jLabel.setText ("A somewaht long message I would not want to
stop");
jLabel.validate();

Related

How to make Frame/Panel fit label of text with fixed width but variable height

I have a label with an unknown amount of text. I need to display this label in a panel. The panel must have a fixed width, but the height needs to be changed to adjust to perfectly wrap whatever the text turns out to be.
So, suppose I have a limit on width of 400 pixels. The text it has to display turns out be 80 words. I need to make this text wrap onto new lines, so its basically a paragraph that is 400 pixels wide, and a previously unknown height. The height of the container needs to be no bigger than is necessary to display the paragraph.
I would love to be able to do this with some sort of layout manager that will work when I resize the frame, so if the width limit changes to say 500 pixels, the height of the label containing the existing paragraph will resize so that there is never more height that is necessary to display the label.
Think of it like someone posting an answer to this question on Stack Overflow. The width of your response is limited to the width of the div in the HTML of this site, but it's going to adjust the height of your div so that it fits your entire answer, no more and no less. I feel like I'm going crazy here; this seems like such basic functionality there has to be a simple way of doing it in Java Swing.
Here is an example of what I'm talking about. Here is a long sentence in a single line without any width restriction.
However, that's too wide because there's a 400 pixel width restriction. It needs to look like this:
Is there a way I can accomplish this wrapping + fitting height to contents with a layout manager, hopefully a box manager? Could you please give an example of the code? It needs to give the correct height for the label based on the amount of text, and I'd really like it to work when the frame gets resized as well.
Here is what I have. It doesn't work because it specifies the height based on the example text, but I need to be able to deal with a variable amount of text, so I can plug in any paragraph and the height of the label will be correct.
public class Playground {
public static void main(String[] args) {
JFrame myFrame = new JFrame();
myFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
myFrame.setBackground(Color.red);
myFrame.setSize(new Dimension(400, 600));
JPanel groupPanel = new JPanel();
myFrame.add(groupPanel);
groupPanel.setLayout(new BoxLayout(groupPanel, BoxLayout.Y_AXIS));
groupPanel.setBackground(Color.green);
JPanel itemPanel = new JPanel();
groupPanel.add(itemPanel);
itemPanel.setLayout(new GridLayout(1,1));
String msg = "<html><p>This is going to be a really long message that says a lot of words but doesnt really say anything. ";
msg += "We want label containing the message (and the itemPanel that contains it) to always have as much height as necessary ";
msg += "to display the message given the width of the frame</p></html>";
JLabel testLabel = new JLabel(msg);
testLabel.setBackground(Color.yellow);
testLabel.setOpaque(true);
itemPanel.setPreferredSize(new Dimension(400, 64));
itemPanel.setMinimumSize(new Dimension(400, 64));
itemPanel.setMaximumSize(new Dimension(400, 64));
itemPanel.add(testLabel);
myFrame.pack();
myFrame.setVisible(true);
}
}
This was a previous answer that helped by getting the frame to pack around a 400px paragraph:
If the only reason you need HTML is for wrapping, then maybe you can
use a JTextArea instead:
//JLabel testLabel = new JLabel(msg);
JTextArea testLabel = new JTextArea();
testLabel.setText(msg);
testLabel.setLineWrap( true );
testLabel.setWrapStyleWord( true );
testLabel.setSize(400, 1);
The setSize(...) statement will provide the hint for the text area on
when to wrap so it can calculate its actual preferred size.
You can always set the properties of the text area to make is look
like a label.
It helps when the frame is initialized, but when I resize the frame the height of the label doesn't change, so maybe I just have to keep calling pack? I'm not sure how I would place that in an event handler though.
Back to the JLabel and HTML:
import java.awt.Color;
import java.awt.Dimension;
import java.awt.GridLayout;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
public class Playground {
public static void main(String[] args) {
JFrame myFrame = new JFrame();
myFrame.setAlwaysOnTop(true);
myFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
myFrame.setPreferredSize(new Dimension(350, 130));
JPanel groupPanel = new JPanel();
groupPanel.setLayout(new GridLayout(1,1));
String msg = "<html><p align='justify'>This is going to be a really long "
+ "message that says a lot of words but doesnt really say anything. "
+ "We want label containing the message (and the itemPanel that "
+ "contains it to always have as much height as necessary to display "
+ "the message given the width of the frame.</p></html>";
JLabel testLabel = new JLabel(msg);
testLabel.setBackground(Color.yellow);
testLabel.setVerticalAlignment(JLabel.TOP);
testLabel.setOpaque(true);
groupPanel.add(testLabel);
myFrame.add(groupPanel);
myFrame.pack();
myFrame.setVisible(true);
myFrame.setLocationRelativeTo(null);
}
}
And here is what the code does:

Java split and replace are not working as expected, removing more than regex limiters

I was writing a program and noticed that in certain cases I would run into an exception. I have isolated the problem to my split and replace methods and ran a test in the main method. Code is as follows.
public class tester
{
public static void main(String[] args)
{
JFrame frame = new JFrame();
frame.setSize(300,300);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new BorderLayout());
JPanel panel = new JPanel();
JPanel panel2 = new JPanel();
frame.add(panel, BorderLayout.CENTER);
//create text box
JTextArea textArea = new JTextArea(15,10);
textArea.setEditable(true);
textArea.setText("");
panel.add(textArea);
frame.setVisible(true);
frame.add(panel2, BorderLayout.SOUTH);
String s = textArea.getText().replace("[a-z]", "");
String[] parts = s.split("\\=|\\-|\\/|\\*|\\+|\\[a-z]");
JButton b = new JButton("something");
panel2.add(b);
b.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
textArea.setText(s);
}
});
}
}
Specifically at the line in which
String s = textArea.getText().replace("[a-z]", "");
String[] parts = s.split("\\=|\\-|\\/|\\*|\\+|\\[a-z]");
the regex limiters are used.
Typing a test input into the textArea with a string such as 123asdv1+asd-
The expected output once the button should be pressed should be the string:
1231+- when s is called.
However, actual output once pressed is in fact an empty string, blank.
parts is used in my original program to store the numbers into a double variable for use in a calculation, but it was added here for sake of consistency.
It would be very helpful if someone could tell me what i've done wrong, my original program is meant to fetch all the numbers between a special symbol such as + or - to be stored and used for a calculation. If an illegal operation was met, it would print an error message onto the text area and continue from where it left off before the error, this is where I am running into the problem.

When typing into JTextArea, text in JLabel moves

I'm making a simple GUI and have a problem.
This is my code :
JFrame jFrame = new JFrame();
jFrame.setTitle("Simple Editor");
jFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
jFrame.setLocation(50,50);
jFrame.setResizable(true);
Box box = new Box(BoxLayout.Y_AXIS);
JTextArea jTextArea = new JTextArea();
jTextArea.setPreferredSize(new Dimension(470,500));
JLabel jLabel = new JLabel();
box.add(jTextArea);
box.add(jLabel);
jLabel.setText("Font type : " + Main.fontType + " font size : " + Main.size
+ " background color : " + Main.backgroundColor
+ " font color : " + Main.fontColor);
jFrame.setContentPane(box);
jFrame.pack();
jFrame.setVisible(true);
When I typing something in JTextArea, text in JLabel is moving. I can't figure out how to solve this. Maybe some component between them? Any advice and help is welcome.
This looks like an artifact of how the Box is calculating sizes and locations. Note that some components and layout managers do not use setPreferredSize, or only take it as a hint, or use it as only one part of a computation, or etc. so it cannot be depended upon as a reliable method to set the size of a component.
In this case, I would hypothesize what is going on is something like: BoxLayout generally uses minimum/maximum sizes, not preferred sizes, and the min/max of a JTextArea is computed based on its text content. As the text changes, the size is recalculated so the layout changes too.
In general if you have a text area, you should put it in a JScrollPane instead:
Box box = new Box(BoxLayout.Y_AXIS);
JTextArea jTextArea = new JTextArea();
JScrollPane jScrollPane = new JScrollPane(jTextArea);
jScrollPane.getViewport().setPreferredSize(new Dimension(470,500));
JLabel jLabel = new JLabel();
box.add(jScrollPane);
box.add(jLabel);
This way when the text content changes in the JTextArea it can simply do its thing, recalculating its size, and flow out the side of the scroll pane.
Also see How to Use Scroll Panes, How to Use Text Areas.
Per Andrew's comment, here are a couple ways to set the initial size of the scroll pane which are perhaps more reliable than setting the viewport's preferred size explicitly:
// specify rows & columns
JTextArea jTextArea = new JTextArea(20, 20);
// specify preferred scrollable viewport size
JTextArea jTextArea = new JTextArea() {
#Override
public Dimension getPreferredScrollableViewportSize() {
return new Dimension(470,500);
}
};
jTextArea.addKeyListener(new KeyAdapter() {
#Override
public void keyTyped(KeyEvent e) {
jLabel.setText(jTextArea.getText());
}
});
where,
jTextArea - your name object of JTextArea class
jLabel - your name object of JLabel class
You add text in the textarea and text in the label is changing. I think, this code help you to decide your problem.

Inserting text in JTextArea

i am developing a simple application in Java and i wanted to know if there is any way i can insert additional text(somewhere in the middle of a sentence) inside a textarea , which is not empty, at a position where the cursor is placed on the click of some component. Can someone please direct me how to go about getting it done
If this is a JTextArea component you can use the .append method to add text to the end of the text area, or the .insert method to insert the new text at a specific position.
If you need to insert the text at the current caret position use the .getCaretPosition method
textArea.replaceSelection(text);
From the API:
Replaces the currently selected content with new content represented
by the given string. If there is no selection this amounts to an
insert of the given text
Check out: JTextComponent.getCaretPosition().
The method getCaretPosition() is inherited by JTextArea, you can use it to get the cursor position. Then you can use JTextArea.insert(String str, int pos) to insert text at that position.
Sample:
JFrame frame = new JFrame();
frame.setLayout(new BorderLayout());
final JTextArea jta = new JTextArea("Hello world\nHello world\nHello world");
JButton btn = new JButton("Add");
btn.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
int pos = jta.getCaretPosition(); //get the cursor position
jta.insert("Some more", pos); //insert your text
}
});
frame.add(jta, BorderLayout.CENTER);
frame.add(btn, BorderLayout.SOUTH);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setVisible(true);

removing horizontal scrollbar for textarea

I'm using Java Swing. I have a textarea in a panel. I don't need a horizontal scrollbar for that textArea, only a vertical scrollbar is needed. I disabled auto scrollbar options, but still the horizontal scrollbar is working. Please help me in thz.
ta.setLineWrap(true)
Sets the line-wrapping policy of the
text area. If set to true the lines
will be wrapped if they are too long
to fit within the allocated width. If
set to false, the lines will always be
unwrapped
Scroll bar comes into text area when you are making your text area too small. This is because your the default column number in netbeans text area is 20.
If you don't want the scroll bar being displayed , then take the textarea properties and change the column number to a value according to your size (say 10).
And the scrollbar will not be shown.
Two examples, the line wrap method and the scroll pane method:
public class Test {
public static void main(String[] args) {
// example text
String rep = "The quick brown fox jumps over the lazy dog.";
String all = rep;
for(int i = 0; i < 100; i++)
all += "\n" + rep;
// create the line wrap example
JTextArea first = new JTextArea(all);
first.setLineWrap(true);
// create the scroll pane example
JScrollPane second =
new JScrollPane(new JTextArea(all),
JScrollPane.VERTICAL_SCROLLBAR_ALWAYS,
JScrollPane.HORIZONTAL_SCROLLBAR_NEVER);
// lay it out
JFrame f = new JFrame("Test");
f.setLayout(new GridLayout(1,2));
f.add(first);
f.add(second);
f.setSize(400, 300);
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.setVisible(true);
}
}
JTextPane don't have a method to enable or disable line wrap, one best choice is:
private JTextPane noWrapTextPane = new JTextPane() {
#Override
public boolean getScrollableTracksViewportWidth() {
return getUI().getPreferredSize(this).width
<= getParent().getSize().width;
}
};

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