Java tutorial
/* * Copyright (c) 1997, 2019, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package javax.swing.plaf.basic; import sun.swing.SwingUtilities2; import java.awt.*; import java.beans.PropertyChangeEvent; import java.beans.PropertyChangeListener; import javax.swing.*; import javax.swing.BorderFactory; import javax.swing.border.Border; import javax.swing.plaf.ToolTipUI; import javax.swing.plaf.ComponentUI; import javax.swing.plaf.UIResource; import javax.swing.text.View; /** * Standard tool tip L&F. * * @author Dave Moore */ public class BasicToolTipUI extends ToolTipUI { static BasicToolTipUI sharedInstance = new BasicToolTipUI(); /** * Global <code>PropertyChangeListener</code> that * <code>createPropertyChangeListener</code> returns. */ private static PropertyChangeListener sharedPropertyChangedListener; private PropertyChangeListener propertyChangeListener; /** * Returns the instance of {@code BasicToolTipUI}. * * @param c a component * @return the instance of {@code BasicToolTipUI} */ public static ComponentUI createUI(JComponent c) { return sharedInstance; } /** * Constructs a new instance of {@code BasicToolTipUI}. */ public BasicToolTipUI() { super(); } public void installUI(JComponent c) { installDefaults(c); installComponents(c); installListeners(c); } public void uninstallUI(JComponent c) { // REMIND: this is NOT getting called uninstallDefaults(c); uninstallComponents(c); uninstallListeners(c); } /** * Installs default properties. * * @param c a component */ protected void installDefaults(JComponent c) { LookAndFeel.installColorsAndFont(c, "ToolTip.background", "ToolTip.foreground", "ToolTip.font"); LookAndFeel.installProperty(c, "opaque", Boolean.TRUE); componentChanged(c); } /** * Uninstalls default properties. * * @param c a component */ protected void uninstallDefaults(JComponent c) { LookAndFeel.uninstallBorder(c); } /* Unfortunately this has to remain private until we can make API additions. */ private void installComponents(JComponent c) { BasicHTML.updateRenderer(c, ((JToolTip) c).getTipText()); } /* Unfortunately this has to remain private until we can make API additions. */ private void uninstallComponents(JComponent c) { BasicHTML.updateRenderer(c, ""); } /** * Registers listeners. * * @param c a component */ protected void installListeners(JComponent c) { propertyChangeListener = createPropertyChangeListener(c); c.addPropertyChangeListener(propertyChangeListener); } /** * Unregisters listeners. * * @param c a component */ protected void uninstallListeners(JComponent c) { c.removePropertyChangeListener(propertyChangeListener); propertyChangeListener = null; } /* Unfortunately this has to remain private until we can make API additions. */ private PropertyChangeListener createPropertyChangeListener(JComponent c) { if (sharedPropertyChangedListener == null) { sharedPropertyChangedListener = new PropertyChangeHandler(); } return sharedPropertyChangedListener; } public void paint(Graphics g, JComponent c) { Font font = c.getFont(); FontMetrics metrics = SwingUtilities2.getFontMetrics(c, g, font); Dimension size = c.getSize(); g.setColor(c.getForeground()); // fix for bug 4153892 String tipText = ((JToolTip) c).getTipText(); if (tipText == null) { tipText = ""; } Insets insets = c.getInsets(); Rectangle paintTextR = new Rectangle(insets.left + 3, insets.top, size.width - (insets.left + insets.right) - 6, size.height - (insets.top + insets.bottom)); View v = (View) c.getClientProperty(BasicHTML.propertyKey); if (v != null) { v.paint(g, paintTextR); } else { g.setFont(font); SwingUtilities2.drawString(c, g, tipText, paintTextR.x, paintTextR.y + metrics.getAscent()); } } public Dimension getPreferredSize(JComponent c) { Font font = c.getFont(); FontMetrics fm = c.getFontMetrics(font); Insets insets = c.getInsets(); Dimension prefSize = new Dimension(insets.left + insets.right, insets.top + insets.bottom); String text = ((JToolTip) c).getTipText(); if (text == null) { text = ""; } else { View v = (c != null) ? (View) c.getClientProperty("html") : null; if (v != null) { prefSize.width += (int) v.getPreferredSpan(View.X_AXIS) + 6; prefSize.height += (int) v.getPreferredSpan(View.Y_AXIS); } else { prefSize.width += SwingUtilities2.stringWidth(c, fm, text) + 6; prefSize.height += fm.getHeight(); } } return prefSize; } public Dimension getMinimumSize(JComponent c) { Dimension d = getPreferredSize(c); View v = (View) c.getClientProperty(BasicHTML.propertyKey); if (v != null) { d.width -= v.getPreferredSpan(View.X_AXIS) - v.getMinimumSpan(View.X_AXIS); } return d; } public Dimension getMaximumSize(JComponent c) { Dimension d = getPreferredSize(c); View v = (View) c.getClientProperty(BasicHTML.propertyKey); if (v != null) { d.width += v.getMaximumSpan(View.X_AXIS) - v.getPreferredSpan(View.X_AXIS); } return d; } /** * Invoked when the <code>JCompoment</code> associated with the * <code>JToolTip</code> has changed, or at initialization time. This * should update any state dependent upon the <code>JComponent</code>. * * @param c the JToolTip the JComponent has changed on. */ private void componentChanged(JComponent c) { JComponent comp = ((JToolTip) c).getComponent(); if (comp != null && !(comp.isEnabled())) { // For better backward compatibility, only install inactive // properties if they are defined. if (UIManager.getBorder("ToolTip.borderInactive") != null) { LookAndFeel.installBorder(c, "ToolTip.borderInactive"); } else { LookAndFeel.installBorder(c, "ToolTip.border"); } if (UIManager.getColor("ToolTip.backgroundInactive") != null) { LookAndFeel.installColors(c, "ToolTip.backgroundInactive", "ToolTip.foregroundInactive"); } else { LookAndFeel.installColors(c, "ToolTip.background", "ToolTip.foreground"); } } else { LookAndFeel.installBorder(c, "ToolTip.border"); LookAndFeel.installColors(c, "ToolTip.background", "ToolTip.foreground"); } } private static class PropertyChangeHandler implements PropertyChangeListener { public void propertyChange(PropertyChangeEvent e) { String name = e.getPropertyName(); if (name.equals("tiptext") || "foreground".equals(name) || "font".equals(name) || SwingUtilities2.isScaleChanged(e)) { // remove the old html view client property if one // existed, and install a new one if the text installed // into the JLabel is html source. JToolTip tip = ((JToolTip) e.getSource()); String text = tip.getTipText(); BasicHTML.updateRenderer(tip, text); } else if ("component".equals(name)) { JToolTip tip = ((JToolTip) e.getSource()); if (tip.getUI() instanceof BasicToolTipUI) { ((BasicToolTipUI) tip.getUI()).componentChanged(tip); } } } } }