I currently have a JLabel embedded in a JTextPane using this:
import javax.swing.*;
import javax.swing.text.*;
public class MainFrame
{
JFrame mainFrame = new JFrame("Main Frame");
JTextPane textPane = new JTextPane();
public MainFrame()
{
String[] components = {"Title", "\n"};
String[] styles = {"LABEL_ALIGN", "LEFT_ALIGN"};
StyledDocument sd = textPane.getStyledDocument();
Style DEFAULT_STYLE = StyleContext.getDefaultStyleContext().getStyle(StyleContext.DEFAULT_STYLE);
Style LEFT_STYLE = sd.addStyle("LEFT_ALIGN", DEFAULT_STYLE);
StyleConstants.setAlignment(LEFT_STYLE, StyleConstants.ALIGN_LEFT);
Style CENTER_STYLE = sd.addStyle("CENTER_ALIGN", DEFAULT_STYLE);
StyleConstants.setAlignment(CENTER_STYLE, StyleConstants.ALIGN_CENTER);
JLabel titleLbl = new JLabel("Title");
Style LABEL_STYLE = sd.addStyle("LABEL_ALIGN", DEFAULT_STYLE);
StyleConstants.setAlignment(LABEL_STYLE, StyleConstants.ALIGN_CENTER);
StyleConstants.setComponent(LABEL_STYLE, titleLbl);
for(int i = 0; i < components.length; i++)
{
try
{
sd.insertString(sd.getLength(), components[i], sd.getStyle(styles[i]));
sd.setLogicalStyle(sd.getLength(), sd.getStyle(styles[i]));
}
catch(BadLocationException e)
{
e.printStackTrace();
}
}
mainFrame.add(textPane);
mainFrame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
mainFrame.setLocationRelativeTo(null);
mainFrame.setExtendedState(JFrame.MAXIMIZED_BOTH);
mainFrame.pack();
mainFrame.setVisible(true);
}
public static void main(String[] args)
{
SwingUtilities.invokeLater(MainFrame::new);
}
}
How can I make the label un-deletable? Because whenever I hold backspace, the label ends up getting removed from the JTextPane
You might be able to use a NavigationFilter to prevent the removal of the component at the beginning of the text pane. Check out: How to make part of a JTextField uneditable for an example of this approach. In this case the label represents a single character so the prefix length would be set to 1. Or maybe you can just use the prefix concept itself and don't even use the JLabel.
Otherwise, you might be able to create a custom DocumentFilter. Check out the section from the Swing tutorial on Implementing a DocumentFilter for the basics.
So you would need to track the offset off the location of the component. Then in the remove(...) method of the filter you would need to check if you are removing data in the range of your offset. If so you would ignore the remove.
Of course the offset can dynamically change if you add or remove text before the label so you would need to manage that as well.
Or you can check out the Protected Text Component which attempts to manage all of that for you.
Why not just put your title label outside the text area? That seems more intuitive.
It looks like there's no real way to avoid this while still allowing the textarea to be editable. You could place the label above the text frame so that it occupies the same space, or above the text frame so that it behaves like a proper title.
Unfortunately, the nature of the textarea is that all of its subcomponents are editable or none of them are.
Related
I am using MigLayout 3.5.5, as the newer updates are not compatible with my older code.
Problem
When setting text to a JTextPane in a MigLayout, the JTextPane will take double the space (according to font size) IF the text I am setting the JTextPane contains space characters. It does not happen all the time, but in the specific program I am making, it happens frequently.
The program's goal is to present information in a letter-by-letter basis, so there is a button that updates the text to the next letter. However, the text bounces around, because the JTextPane is sometimes occupying more space than usual. I identified a certain pattern to the height differences.
Pattern
A new line indicates that I added a letter.
"|" represents a space character in the text.
"Space" means JTextPane is taking double the space.
Full String: "The quick brown fox jumps over the lazy dog."
T
Th
The
The|
The|q (Space)
The|qu
The|qui (Space)
The|quic
The|quick (Space)
The|quick|
Note: I stopped the pattern here, because from this point on (starting with The|quick|b), every single letter addition resulted in the JTextPane occupying double its height.
I've already tried printing out the letter-by-letter text to the console to see if there were any new line characters within the text being added, but to no avail. I also thought it might be a problem with the automatic wrapping of the JTextPane, but the text I inserted isn't quite long enough to wrap in the JFrame's size.
Here is a short example to reproduce the behavior:
public class MainFrame extends JFrame {
int currentLetter = 1;
final String FULL_TEXT = "The quick brown fox jumps over the lazy dog.";
JTextPane text;
JButton addLetter;
MainFrame() {
setSize(500, 500);
setLayout(new MigLayout("align center, ins 0, gap 0"));
addElements();
setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
MainFrame application = new MainFrame();
}
});
}
private void addElements() {
text = new JTextPane();
text.setEditable(false);
text.setFont(new Font("Times New Roman", Font.BOLD, 19));
text.setForeground(Color.WHITE);
text.setBackground(Color.BLACK);
add(text, "alignx center, wmax 80%, gapbottom 5%");
addLetter = new JButton("Add Letter");
addLetter.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
if (currentLetter != FULL_TEXT.length()) {
currentLetter++;
updateText();
}
}
});
add(addLetter, "newline, alignx center");
updateText();
}
private void updateText() {
String partialText = new String();
for (int letter = 0; letter < currentLetter; letter++) {
partialText += FULL_TEXT.toCharArray()[letter];
}
text.setText(partialText);
}
}
Why am I using JTextPane?
I tried using JLabel for this task, and it worked well... until the text was long enough to wrap. Then, when I used HTML within the JLabel text to wrap it, every time I updated the text, it would take time for the HTML to render and result in some pretty nasty visual effects.
Next, I tried JTextArea to disguise it as a JLabel, since it not only has line wrapping, but word wrapping as well. It was a great solution, until I found out that I couldn't use a center paragraph alignment in a JTextArea.
So I settled for a JTextPane, which will work well if only I got rid of the extra space at the bottom of it.
Thanks in advance for your help!
The solution is to append text by using the insertString() method on the StyledDocument of the JTextPane instead of using setText() on the JTextPane itself.
For example, instead doing this every time:
JTextPane panel = new JTextPane();
panel.setText(panel.getText() + "test");
You should do this:
JTextPane panel = new JTextPane();
StyledDocument document = panel.getStyledDocument();
document.insertString(document.getLength(), "test", null);
And of course you need to catch the BadLocationException.
Then the space disappears. Here's the question where I found my answer to the rendering problem: JTextPane appending a new string
The answers to those questions don't address the problem with the space, but they do show the correct way to edit text in the JTextPane.
I'm making a simple Jeopardy-esque game:
using Java Swing. It's obviously a JFrame with a JPanel in it and buttons in rows.
Now what I need is to add a layered panel with a centered and wrapped text in it:
Which I can remove later. I already tried using JTextPane and JTextArea and JPanel, none of those want to even display. The best effect I have achieved with AWT Panel, it does display but I can't center or wrap text in it.
Here's some code for which I appologise, I would usually try to make it short and readable but since it's not working I don't know what to do with it to make ti look better:
JLabel questionLabel = new JLabel(questionList.get(randomNumber).getQuestion(), SwingConstants.CENTER);
Font font = new Font("Arial", Font.PLAIN, 20);
//------------------JTextPane--------------------
JTextPane questionPane = new JTextPane();
questionPane.setForeground(Color.WHITE);
questionPane.setSize(gameWidth, gameHeight);
questionPane.setText(questionList.get(randomNumber).getQuestion());
questionPane.setFont(font);
questionPane.setEditable(false);
//------------------AWT panel--------------------
Panel awtPanel = new Panel();
awtPanel.setBackground(Color.blue);
awtPanel.setSize(game.getWidth(),game.getHeight());
Label labelQuestion = new Label("<html>" + questionList.get(randomNumber).getQuestion() + "</html>", Label.CENTER);
labelQuestion.setFont(font);
awtPanel.setForeground(Color.white);
awtPanel.add(labelQuestion);
//------------------JPanel-----------------------
JPanel layeredPanel = new JPanel();
layeredPanel.setBackground(Color.blue);
layeredPanel.setSize(game.getWidth(),game.getHeight());
JLabel jLabelQuestion = new JLabel("<html>" + questionList.get(randomNumber).getQuestion() + "</html>", SwingConstants.CENTER);
jLabelQuestion.setFont(font);
layeredPanel.setForeground(Color.WHITE);
layeredPanel.add(jLabelQuestion, BorderLayout.CENTER);
game.getLayeredPane().add(layeredPanel, JLayeredPane.DEFAULT_LAYER);
try {
Thread.sleep(3000);
} catch (InterruptedException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
button.setEnabled(false);
font = new Font("Arial", Font.PLAIN, 16);
button.add(jLabelQuestion, BorderLayout.CENTER);
button.setDisabledIcon(new ImageIcon(source.getScaledInstance(gameWidth/4, gameHeight/5, java.awt.Image.SCALE_SMOOTH)));
questionList.remove(randomNumber);
logger.info(questionList.size());
game.getLayeredPane().remove(layeredPanel);
UPDATE: I chnaged to SWT rather than Swing, and I use the StackLayout with a few Composites in it, and just change between them as I see fit.
You can generally solve issues like this with a JLabel.
I would recommend encapsulating the above grid in the BorderLayout.CENTER of another pane, perhaps a new content pane. Then, add the caption to BorderLayout.NORTH.
As a more tangible example,
private void createContent() {
this.getContentPane().setLayout(new BorderLayout());
//establish the panel currently set as center, here labeled "everythingElse"
this.getContentPane().add(everythingElse, BorderLayout.CENTER);
//Create a JLabel with your caption
JLabel jlbl = new JLabel("Question");
//format that caption, most details being rather obvious, but most importantly:
jlbl.setHorizontalAlignment(SwingConstants.CENTER); //keeps text centered
this.getContentPane().add(jlbl, BorderLayout.NORTH); //add it to the top of the panel
//...other cleanup operations...
}
The issue with grid panes is that they have a limited tolerance for the number of components visible in them. If you overload one, it won't show. For BorderLayout panes, you can easily swap new items into and out of them.
For efficiency's sake, I might recommend compiling this JLabel as a final somewhere else in your code, and holding onto it for when you need it. This way, you will also dodge overhead from repeatedly creating the label object.
Lastly, avoid AWT whenever you can. It's been deprecated for an excess of ten years, and if you do use it you will run into numerous critical problems involving heavyweight and lightweight component incompatibilities. If you intend to use another windowing kit, consider implementing the new standard, JavaFX, with a JFXPane-- it's much more tolerant of HTML syntax, as well.
I am trying to create a simple GUI that simulates a record store. I am still in the beginning stages.
I am running into trouble when I try to add text to describe what the user is expected to enter in the text field.
In addition, I am also having trouble positioning every textfield on its own line. In other words if there is space for two textfields in one line, then it displays in one line, and I am trying to display every text field on its own line.
This is what I tried so far:
item2 = new JTextField("sample text");
However the code above just adds default text within the text field, which is not what I need :/
I appreciate all the help in advance.
public class MyClass extends JFrame{
private JTextField item1;
private JTextField item2;
public MyClass(){
super("Matt's World of Music");
setLayout(new FlowLayout());
item1 = new JTextField();
item2 = new JTextField();
add(item1);
add(item2);
thehandler handler = new thehandler();
item1.addActionListener(handler);
item2.addActionListener(handler);
}
}
For your first problem, you need to use a JLabel to display your text. The constructor is like this:
JLabel label = new JLabel("Your text here");
Works really well in GUI.
As for getting things on their own lines, I recommend a GridLayout. Easy to use.
In your constructor, before adding anything, you do:
setLayout(new GridLayout(rows,columns,x_spacing,y_spacing));
x_spacing and y_spacing are both integers that determine the space between elements horizontally and vertically.
Then add like you have done. Fiddle around with it and you'll get it worked out.
So your final would look like:
setLayout(new GridLayout(2,2,10,10));
add(new JLabel("Text 1"));
add(text1);
add(new JLabel("text 2"));
add(text2);
You could just use a JLabel to label your textfields.
JLabel label1 = new JLabel("Item 1: ");
add(label1);
add(item1);
If you really want text inside the fields, you could set the text in the field with the constructor, and then add a MouseListener to clear the text on click:
item1 = new JTextField("Text");
item1.addMouseListener(new MouseAdapter() {
public void mouseClicked(MouseEvent e) {
if (item1.getText().equals("Text")) // User has not entered text yet
item1.setText("");
}
});
Or, (probably better) use a FocusListener:
item1 = new JTextField("Text");
item1.addFocusListener(new FocusListener() {
public void focusGained(FocusEvent e) {
if (item1.getText().equals("Text")) // User has not entered text yet
item1.setText("");
}
public void focusLost(FocusEvent e) {
if (item1.getText().equals("")) // User did not enter text
item1.setText("Text");
}
});
As for layout, to force a separate line, you use use a Box.
Box itemBox = Box.createVerticalBox();
itemBox.add(item1);
itemBox.add(item2);
add(itemBox);
Make:
item1 = new JTextField(10);
item2 = new JTextField(10);
that should solve problem with width of JTextField.
For beginning use GridLayout to display JTextField in one line. After that I strongly recomend using of MIG Layout http://www.migcalendar.com/miglayout/whitepaper.html.
put JLabel next to JTextField to describe what the user is expected to enter in the text field.
JLabel lbl = new JLabel("Description");
or you could also consider using of toolTipText:
item1.setToolTipText("This is description");
For making a form in Java Swing, I always recommend the FormLayout of JGoodies, which is designed to ... create forms. The links contains an example code snippet, which I just copy-pasted here to illustrate how easy it is:
public JComponent buildContent() {
FormLayout layout = new FormLayout(
"$label, $label-component-gap, [100dlu, pref]",
"p, $lg, p, $lg, p");
PanelBuilder builder = new PanelBuilder(layout);
builder.addLabel("&Title:", CC.xy(1, 1));
builder.add(titleField, CC.xy(3, 1));
builder.addLabel("&Author:", CC.xy(1, 3));
builder.add(auhtorField, CC.xy(3, 3));
builder.addLabel("&Price:", CC.xy(1, 5));
builder.add(priceField, CC.xy(3, 5));
return builder.getPanel();
}
Now for the description:
Use a label in front of the textfield to give a very short description
You can put a longer description in the textfield as suggested by #Alden. However, if the textfield is for short input, nobody will be able to read the description
You can use a tooltip (JComponent#setTooltipText) to put a longer description. Those tooltips also accept basic html which allows some formatting. Drawback of the tooltips is that the user of your application has to 'discover' that feature as there is no clear indication those are available
You can put a "help-icon" (like e.g. a question mark) after each text field (use a JButton with only an icon) where on click you show a dialog with a description (e.g. by using the JOptionPane class)
You can put one "help-icon" on each form which shows a dialog with a description for all fields.
Note for the dialog suggestion: I wouldn't make it a model one, allowing users to open the dialog and leave it open until they are finished filling in the form
I have a JTextPane and I have some text within that JTextPane. However, because I have been using HTML within the Pane, the text seems to have been automatically changed to Times New Roman.
I'm trying to set the font type within the JTextPane to the default font of the GUI (the font of the JTextPane when it's not HTML). However I can't just set the font to one font because it differs from operating system, therefore I want to find a way to get the default font and then change the text I have to the default font.
To demonstrate how the text is swapped to Times New Roman when converted, the following code is the format I have used. How could I change it to achieve my goal?
import javax.swing.JFrame;
import javax.swing.JTextPane;
public class GUIExample {
public static void main(String[] args) {
JFrame frame = new JFrame("My App");
frame.setSize(300,300);
JTextPane pane = new JTextPane();
pane.setContentType("text/html");
pane.setText("<html><b>This is some text!</b></html>");
frame.add(pane);
frame.setVisible(true);
}
}
Thanks!
The following will do the trick:
pane.putClientProperty(JEditorPane.HONOR_DISPLAY_PROPERTIES, true);
(Note that JTextPane extends JEditorPane.)
Update (Aug 2016):
For the setting to survive Look & Feel and system changes (e.g. Fonts changed in the Windows Control Panel) the line can be placed here:
#Override
public void updateUI() {
super.updateUI();
putClientProperty(JEditorPane.HONOR_DISPLAY_PROPERTIES, true);
}
(This is also called during construction.)
Simplest way is probably something like this:
string fontfamily = pane.getFont().getFamily();
That will give you the default font. Then just apply it using CSS:
pane.setText("<html><body style=\"font-family: " + fontfamily + "\"<b>This is some text!</b></html>");
The JComponent html renderer uses its own font, and not that of the JComponent. In order to get the component to render the same, you need to set the font attributes in the html string. Among other things, you will need to set the font family, size, bold/italics, etc.
As an example, you could do the following:
JTextPane pane = new JTextPane();
Font font = pane.getFont();
pane.setContentType("text/html");
pane.setText("<html><font face=\"" + font.getFamily() + "\" size=\"" + font.getSize() + "\"></font>This is some text!</html>");
It would be fairly trivial to create a function that does this for you. Pass it a JComponent and a string, and it would create the html text for you, including all the font tags.
I am making a pig latin translater using JFrame in Java. Here's my problem; I have a "quit" button that closes the program; that doesn't matter, but what does is I have no control over its alignment (or any other component). I tried using quit.setAlignmentY(BOTTOM_ALIGNMENT); in the hopes that that would align it to the bottom of the page, but nothing changed. Some help here, please?
In case anyone needs it, here's the code;
public class Main extends JFrame{
private static JLabel label, result;
private static JTextField english;
private static JButton quit;
private static String originalResult = "Translated to pig latin: ";
private static ArrayList<String> beginningSymbols = new ArrayList<>();
private static ArrayList<String> endingSymbols = new ArrayList<>();
//prompt for string to translate, display final result
public Main(){
super("Pig Latin Translator");
setLayout(new FlowLayout());
setVisible(true);
setSize(600, 300);
setDefaultCloseOperation(EXIT_ON_CLOSE);
translatingHandler th = new translatingHandler();
label = new JLabel("Enter a phrase to translate into pig latin, then press enter:");
english = new JTextField(15);
result = new JLabel(originalResult);
quit = new JButton("Quit program");
english.addActionListener(th);
quit.addActionListener(th);
quit.setAlignmentY(BOTTOM_ALIGNMENT);
add(label);
add(english);
add(quit);
add(result);
english.requestFocus();
}
public static void main(String[] args){
new Main();
}
...
}
The JButton quit is the one I'm trying to align to the bottom of the page. Thanks!
Actually you are using FlowLayout. If you take a look at FlowLayout tutorials it is mentioned that
The FlowLayout class puts components in a row, sized at their
preferred size. If the horizontal space in the container is too small
to put all the components in one row, the FlowLayout class uses
multiple rows. If the container is wider than necessary for a row of
components, the row is, by default, centered horizontally within the
container.
If you insist on using FlowLayout align your components.
Anyways take a look at Using Layout Managers. For your task appropriate layout managers will be BorderLayout.
But if you need something very flexible use GridBagLayout or MigLayout but they are a little complex to use.
So as #HovercraftFullOfEels suggested try avoiding them.
Welcome to the confusing world of Java Swing. You probably want to look into layout managers. Specifically, BorderLayout might be of interest.