org.fife.ui.SelectableLabel Maven / Gradle / Ivy

/*
 * 10/15/2009
 *
 * SelectableLabel.java - A label that can have its text selected.
 * Copyright (C) 2009 Robert Futrell
 * http://fifesoft.com/rtext
 * Licensed under a modified BSD license.
 * See the included license file for details.
 */
package org.fife.ui;

import java.awt.Color;
import java.awt.Font;
import javax.swing.JTextPane;
import javax.swing.JLabel;
import javax.swing.UIManager;
import javax.swing.plaf.TextUI;
import javax.swing.text.html.HTMLDocument;


/**
 * A "label" component that can have its text selected.
 *
 * @author Robert Futrell
 * @version 1.0
 */
public class SelectableLabel extends JTextPane {

	/**
	 * The color to use when rendering hyperlinks.  If non-null,
	 * this overrides Swing's default.
	 */
	private Color hyperlinkForeground;


	/**
	 * Constructor.
	 */
	public SelectableLabel() {
		this(null);
	}


	/**
	 * Constructor.
	 *
	 * @param text The text to display.  This can be HTML.
	 */
	public SelectableLabel(String text) {
		setText(text);
		labelize();
	}


	/**
	 * Makes this editor pane look like a label.
	 */
	private void labelize() {

		setBorder(null);
		setEditable(false);
		setOpaque(false);
		setBackground(new Color(0, 0, 0, 0)); // Needed for Nimbus

		// In case text component fonts are different from label fonts.
		Font font = UIManager.getFont("Label.font");
		if (font==null) { // Not required to be defined
			font = new JLabel().getFont();
		}
		setFont(font);

		// In case text component fg is different from label fg.
		Color fg = UIManager.getColor("Label.foreground");
		if (fg!=null) {
			//System.out.println("Foreground" + fg);
			setForeground(fg);
		}

		// Some LaFs have different selection colors for editable vs.
		// non-editable text components; we want to use the editable color.
		Color sel = UIManager.getColor("TextField.selectionBackground");
		if (sel!=null) {
			//System.out.println("Selection background: " + sel);
			setSelectionColor(sel);
		}

	}


	/**
	 * Sets the color to use for hyperlinks, when HTML is displayed in this
	 * component.  This can be used to override the default color used
	 * by Swing, if you think a custom color looks better in your LookAndFeel.
	 *
	 * @param fg The new foreground.  Setting this to null will
	 *        cause the default color to be used.
	 */
	public void setHyperlinkForeground(Color fg) {
		this.hyperlinkForeground = fg;
	}


	/**
	 * Sets the text displayed by this label.
	 *
	 * @param text The text to display.  If this begins with
	 *        "<html>", the text will be rendered as
	 *        HTML.
	 */
	public void setText(String text) {
		if (text!=null && text.startsWith("")) {
			setContentType("text/html");
			updateDefaultHtmlFont();
		}
		else {
			setContentType("text/plain");
		}
		super.setText(text);
	}


	/**
	 * Overridden to keep our special properties, to keep us looking like
	 * a label across LookAndFeels.
	 */
	public void setUI(TextUI ui) {
		super.setUI(ui);
		labelize();
		if (getDocument() instanceof HTMLDocument) {
			updateDefaultHtmlFont();
		}
	}


	/**
	 * Add a CSS rule to force body tags to use the default label font
	 * instead of the value in javax.swing.text.html.default.css.  This was
	 * adapted from:
	 * http://explodingpixels.wordpress.com/2008/10/28/make-jeditorpane-use-the-system-font/
	 */
	private void updateDefaultHtmlFont() {

		Color fg = UIManager.getColor("Label.foreground");
		Font font = UIManager.getFont("Label.font");
		// These properties are defined by all standard LaFs, even Nimbus (!),
		// but you never know what crazy LaFs there are...
		if (font==null) {
			font = new JLabel().getFont();
		}
		if (fg==null) {
			fg = new JLabel().getForeground();
		}

		// When rendering HTML, the JEditorPane foreground color is ignored;
		// we have to set it in the CSS as well.  This is only needed for
		// LAF's whose label color isn't (extremely close to) black.
		HTMLDocument doc = (HTMLDocument)getDocument();
		String bodyRule = "body { font-family: " + font.getFamily() +
						"; font-size: " + font.getSize() + "pt" +
						"; color: " + UIUtil.getHTMLFormatForColor(fg) + "; }";
		doc.getStyleSheet().addRule(bodyRule);

		// If this LaF looks to be light-text-on-dark-background,
		// use a light color for hyperlinks.
		Color linkFG = hyperlinkForeground;
		if (linkFG==null) {
			linkFG = UIUtil.getHyperlinkForeground();
		}
		if (linkFG!=null) {
			String aRule = "a { color: " +
					UIUtil.getHTMLFormatForColor(linkFG) + "; }";
			doc.getStyleSheet().addRule(aRule);
		}
		
	}


}