RichTextFX

RichTextFX provides a text area for JavaFX with API to style ranges of text. It is intended as a base for rich-text editors and code editors with syntax highlighting.

Scroll down to Demos to see it in action.

There is plenty of room for enhancements, e.g. displaying line numbers, support for paragraph-level styles (#6), placing arbitrary nodes in the text, copy/paste including style information (#17), ... To give me or someone else more incentive to implement these or other features, you can create a bounty.

Flavors

StyleClassedTextArea

StyleClassedTextArea lets you assign style classes to ranges of text. You can define the style classes in your stylesheet.

Example.java:

area.setStyleClass(from, to, "red");

example.css:

.red { -fx-fill: red; }

This renders the text in the range [from, to) in red.

Note that the style classes are assigned to instances of Text, so you can specify any CSS properties applicable to a Text node.

CodeArea

CodeArea is a variant of StyleClassedTextArea that uses a fixed width font by default, making it a convenient base for source code editors. CodeArea is used in the Java Keywords demo below.

InlineCssTextArea

InlineCssTextArea lets you specify inline CSS for a range of text.

area.setStyle(from, to, "-fx-font-weight: bold;");

Again, you can use any CSS properties applicable to a Text node.

InlineStyleTextArea

InlineStyleTextArea<S> is a more general version of InlineCssTextArea. In the end, there is still inline CSS assigned to Text nodes, but instead of using the CSS string directly, you use an instance of your custom style representation S and provide a way (function) to convert S to CSS string in InlineStyleTextArea constructor.

class MyStyleInfo {
    boolean bold;
    boolean italic;
    
    String toCss() {
        return "-fx-font-weight: " + (bold ? "bold" : "normal") + ";"
               + "-fx-font-style: " + (italic ? "italic" : "normal") + ";";
    }
}

InlineStyleTextArea<MyStyleInfo> area =
        new InlineStyleTextArea<>(new MyStyleInfo(), styleInfo -> styleInfo.toCss());

The first constructor argument is the default style to use for ranges of text where you don't set the style explicitly. The second constructor argument is the function to convert the custom style representation to CSS.

You then assign an instance of your custom style representation to a range of text.

MyStyleInfo styleInfo = ...;

area.setStyle(from, to, styleInfo);

You appreciate the benefits of this approach over InlineCssTextArea when you need to query the style used at a given position in text - you get back an instance of your style representation instead of a CSS string.

MyStyleInfo styleInfo = area.getStyleAt(charIndex);

InlineStyleTextArea is used in the Rich-text demo below.

Requirements

JDK8 is required, because TextFlow, introduced in JavaFX 8.0, is used to render each line. Also, there's a heavy use of lambdas, defender methods and the stream API in the code base.

Demos

1. Automatic highlighting of Java keywords

Run using the pre-built JAR

Download the pre-built "fat" JAR file and run

java -cp richtextfx-demos-fat-yyyymmdd.jar org.fxmisc.richtext.demo.JavaKeywords

or

java -cp richtextfx-demos-fat-yyyymmdd.jar org.fxmisc.richtext.demo.JavaKeywordsAsync

Run from the source repo

gradle JavaKeywords

or

gradle JavaKeywordsAsync

Source code

JavaKeywords.java

JavaKeywordsAsync.java

The former computes highlighting on the JavaFX application thread, while the latter computes highlighting on a background thread.

2. Rich-text editor

Run using the pre-built JAR

Download the pre-built "fat" JAR file and run

java -cp richtextfx-demos-fat-yyyymmdd.jar org.fxmisc.richtext.demo.RichText

Run from the source repo

gradle RichText

Source code

RichText.java

Source code of this demo is dedicated to the public domain.

Use RichTextFX in your project

Method 1: as a managed dependency

Snapshot releases are deployed to Sonatype snapshot repository with these Maven coordinates

Group ID	Artifact ID	Version
org.fxmisc.richtext	richtextfx	1.0.0-SNAPSHOT

Gradle example

repositories {
    maven {
        url 'https://oss.sonatype.org/content/repositories/snapshots/' 
    }
}

dependencies {
    compile group: 'org.fxmisc.richtext', name: 'richtextfx', version: '1.0.0-SNAPSHOT'
}

Sbt example

resolvers += "Sonatype OSS Snapshots" at "https://oss.sonatype.org/content/repositories/snapshots"

libraryDependencies += "org.fxmisc.richtext" % "richtextfx" % "1.0.0-SNAPSHOT"

Method 2: as an unmanaged dependency

Download the latest JAR or fat JAR (including dependencies) and place it on your classpath.

License

GPLv2 with the Classpath Exception

Links

API Documentation
Dropped Features
Known Issues
Java 8 Development Gotchas