Summary

Add APIs to configure the tab size of Text and TextFlow nodes.

Problem

The current tab size is hard coded to 8 spaces. Text editors often allow for a configurable tab size. Something like that is very difficult to implement well in JavaFX with the current implementation of Text and TextFlow. Work-arounds such as inserting spaces instead of tabs results in a poor user experience when navigating the text.

Solution

Introduce a tabSize property and a corresponding -fx-tab-size CSS property to Text and TextFlow nodes, along with APIs to configure and query this property. This integer property will set the tab size as a number of spaces in the current font.

Specification

Text.java

/**
 * The size of a tab stop in spaces.
 * Values less than 1 are treated as 1.
 *
 * @defaultValue 8
 *
 * @since 14
 */
public final IntegerProperty tabSizeProperty() { }
public final void setTabSize(int spaces) { }
public final int getTabSize() { }

TextFlow.java

/**
 * The size of a tab stop in spaces.
 * Values less than 1 are treated as 1. This value overrides the
 * {@code tabSize} of contained {@link Text} nodes.
 *
 * @defaultValue 8
 *
 * @since 14
 */
public final IntegerProperty tabSizeProperty() { }
public final void setTabSize(int spaces) { }
public final int getTabSize() { }

csssref.html

Text

Style class: empty by default

  CSS Property    Values    Default
-fx-tab-size    <integer>      8