Thread: Setting tab size for JEditorPane

Is there a way to set the tab size (either in pixels or space units) for JEditorPane's? I'm using an HTMLDocument, so it doesn't matter if the tab size is set via css styling or from the program itself. If it is indeed being set from a css style sheet, it will likely need to apply to a <pre> tag since that's what I'm using.

What i'm trying to create is a colored syntax highlighting text component using the HTMLEditorKit to facilitate coloring (JTextArea unfortunately requires all text to have the same font/style, not suitable for this application). However, the default tab size for JEditorPane/HTMLDocuments is ~20 spaces, which is way too large. I would also prefer to not force all tabs to be converted into spaces.

Originally Posted by helloworld922

However, the default tab size for JEditorPane/HTMLDocuments is ~20 spaces, which is way too large. I would also prefer to not force all tabs to be converted into spaces.

Strange. For me the tab spacing is much less, more like 8 spaces to start a line and 3 in mid-line, but it is also context dependent to allow for lining up of tabbed elements so tab-delim formats line up properly. I don't know of a way to set it off the top of my head. You may really have to get into the nitty gritty of the backend of a JEditorPane to do so programmatically. Don't think there is a way via css - at least a way that is respected by the limited css capability of a JEditorPane.

You need to set the tab stops to the document, not the view.

Related classes/methods:
DefaultStyledDocument (Java Platform SE 6)
StyleConstants (Java Platform SE 6)
TabSet (Java Platform SE 6)

I haven't done this myself but I'm willing to try to help if you encounter a problem in implementing this. Just post a SSCCE and indicate what's not right with it.

luck, db

I found an article concerning a similar topic (the solution is the last post, with an in-depth discussion at the link in the second to last post):

how can I change the Tab size of JTextPane ?

It's not a JEditorPane, but rather a JTextPane and I don't think this uses the HTMLEditorKit, either. However, I will try to figure out these little issues when I'm more awake

Originally Posted by Example Snippet

textPane.setParagraphAttributes(def,true);

This is actually a JTextPane method. I don't imagine it would be too hard to write an equivalent for JEditorPane, though. Also, JTextPane has access to the HTMLEditorKit, too so I think it makes sense for my application to switch over to using a JTextPane (I picked JEditorPane rather arbitrarily)