I'm using a JTextPane to edit HTML. When I enter newlines in the GUI component and call getText() on the JTextPane, I get a string with newline characters. If I then create a new JTextPane and pass that same text in, the newlines are ignored.
Why doesn't JTextPane insert a <br> tag when a newline is entered? Is there a good workaround for this?
JTextPane test = new JTextPane();
test.setPreferredSize(new Dimension(300, 300));
test.setContentType("text/html");
test.setText("Try entering some newline characters.");
JOptionPane.showMessageDialog(null, test);
String testText = test.getText();
System.out.println("Got text: " + testText);
// try again
test.setText(testText);
JOptionPane.showMessageDialog(null, test);
testText = test.getText();
System.out.println("Got text: " + testText);
Sample output:
<html>
<head>
</head>
<body>
Try entering some newline characters.
What gives?
</body>
</html>
I realize I could convert newlines to HTML line breaks before calling setText, but that would convert the newlines after the HTML and BODY tags as well, and seems dumb.
I've resolved this, the problem was the plain text I was passing in in setText. If I take out the call to setText, the result of JTextPane.getText() is nicely formatted HTML with line breaks correctly encoded.
I believe when I call JTextPane.setText("Try entering some newline characters") it sets the HTMLDocument.documentProperties.__EndOfLine__ to "\n". This document property constant is defined here.
The solution is to make sure you wrap your text in <p> tags when passing it to the JTextPane.setText() method (note, the style attribute is used for any subsequent paragraphs):
textPane1.setText("<p style=\"margin-top: 0\">Try entering some newline characters</p>");
Or, after you pass in plain text, replace the EndOfLineStringProperty (this is more of a hack, I wouldn't recommend it):
textPane1.getDocument().putProperty(DefaultEditorKit.EndOfLineStringProperty, "<br/>\n")