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/* * 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 sun.awt.AppContext; import java.awt.*; import java.awt.event.*; import java.io.Serializable; import javax.swing.*; import javax.swing.border.*; import java.awt.*; import java.awt.event.*; import javax.swing.plaf.ButtonUI; import javax.swing.plaf.UIResource; import javax.swing.plaf.ComponentUI; import javax.swing.text.View; /** * BasicButton implementation * * @author Jeff Dinkins */ public class BasicButtonUI extends ButtonUI { // Visual constants // NOTE: This is not used or set any where. Were we allowed to remove // fields, this would be removed. /** * The default gap between a text and an icon. */ protected int defaultTextIconGap; // Amount to offset text, the value of this comes from // defaultTextShiftOffset once setTextShiftOffset has been invoked. private int shiftOffset = 0; // Value that is set in shiftOffset once setTextShiftOffset has been // invoked. The value of this comes from the defaults table. /** * The default offset of a text. */ protected int defaultTextShiftOffset; private static final String propertyPrefix = "Button" + "."; private static final Object BASIC_BUTTON_UI_KEY = new Object(); // ******************************** // Create PLAF // ******************************** /** * Returns an instance of {@code BasicButtonUI}. * * @param c a component * @return an instance of {@code BasicButtonUI} */ public static ComponentUI createUI(JComponent c) { AppContext appContext = AppContext.getAppContext(); BasicButtonUI buttonUI = (BasicButtonUI) appContext.get(BASIC_BUTTON_UI_KEY); if (buttonUI == null) { buttonUI = new BasicButtonUI(); appContext.put(BASIC_BUTTON_UI_KEY, buttonUI); } return buttonUI; } /** * Returns the property prefix. * * @return the property prefix */ protected String getPropertyPrefix() { return propertyPrefix; } // ******************************** // Install PLAF // ******************************** public void installUI(JComponent c) { installDefaults((AbstractButton) c); installListeners((AbstractButton) c); installKeyboardActions((AbstractButton) c); BasicHTML.updateRenderer(c, ((AbstractButton) c).getText()); } /** * Installs default properties. * * @param b an abstract button */ protected void installDefaults(AbstractButton b) { // load shared instance defaults String pp = getPropertyPrefix(); defaultTextShiftOffset = UIManager.getInt(pp + "textShiftOffset"); // set the following defaults on the button if (b.isContentAreaFilled()) { LookAndFeel.installProperty(b, "opaque", Boolean.TRUE); } else { LookAndFeel.installProperty(b, "opaque", Boolean.FALSE); } if (b.getMargin() == null || (b.getMargin() instanceof UIResource)) { b.setMargin(UIManager.getInsets(pp + "margin")); } LookAndFeel.installColorsAndFont(b, pp + "background", pp + "foreground", pp + "font"); LookAndFeel.installBorder(b, pp + "border"); Object rollover = UIManager.get(pp + "rollover"); if (rollover != null) { LookAndFeel.installProperty(b, "rolloverEnabled", rollover); } LookAndFeel.installProperty(b, "iconTextGap", Integer.valueOf(4)); } /** * Registers listeners. * * @param b an abstract button */ protected void installListeners(AbstractButton b) { BasicButtonListener listener = createButtonListener(b); if (listener != null) { b.addMouseListener(listener); b.addMouseMotionListener(listener); b.addFocusListener(listener); b.addPropertyChangeListener(listener); b.addChangeListener(listener); } } /** * Registers keyboard actions. * * @param b an abstract button */ protected void installKeyboardActions(AbstractButton b) { BasicButtonListener listener = getButtonListener(b); if (listener != null) { listener.installKeyboardActions(b); } } // ******************************** // Uninstall PLAF // ******************************** public void uninstallUI(JComponent c) { uninstallKeyboardActions((AbstractButton) c); uninstallListeners((AbstractButton) c); uninstallDefaults((AbstractButton) c); BasicHTML.updateRenderer(c, ""); } /** * Unregisters keyboard actions. * * @param b an abstract button */ protected void uninstallKeyboardActions(AbstractButton b) { BasicButtonListener listener = getButtonListener(b); if (listener != null) { listener.uninstallKeyboardActions(b); } } /** * Unregisters listeners. * * @param b an abstract button */ protected void uninstallListeners(AbstractButton b) { BasicButtonListener listener = getButtonListener(b); if (listener != null) { b.removeMouseListener(listener); b.removeMouseMotionListener(listener); b.removeFocusListener(listener); b.removeChangeListener(listener); b.removePropertyChangeListener(listener); } } /** * Uninstalls default properties. * * @param b an abstract button */ protected void uninstallDefaults(AbstractButton b) { LookAndFeel.uninstallBorder(b); } // ******************************** // Create Listeners // ******************************** /** * Returns a new instance of {@code BasicButtonListener}. * * @param b an abstract button * @return a new instance of {@code BasicButtonListener} */ protected BasicButtonListener createButtonListener(AbstractButton b) { return new BasicButtonListener(b); } /** * Returns the default gap between a text and an icon. * * @param b an abstract button * @return the default gap between text and an icon */ public int getDefaultTextIconGap(AbstractButton b) { return defaultTextIconGap; } /* These rectangles/insets are allocated once for all * ButtonUI.paint() calls. Re-using rectangles rather than * allocating them in each paint call substantially reduced the time * it took paint to run. Obviously, this method can't be re-entered. */ private static Rectangle viewRect = new Rectangle(); private static Rectangle textRect = new Rectangle(); private static Rectangle iconRect = new Rectangle(); // ******************************** // Paint Methods // ******************************** public void paint(Graphics g, JComponent c) { AbstractButton b = (AbstractButton) c; ButtonModel model = b.getModel(); String text = layout(b, SwingUtilities2.getFontMetrics(b, g), b.getWidth(), b.getHeight()); clearTextShiftOffset(); // perform UI specific press action, e.g. Windows L&F shifts text if (model.isArmed() && model.isPressed()) { paintButtonPressed(g, b); } // Paint the Icon if (b.getIcon() != null) { paintIcon(g, c, iconRect); } if (text != null && !text.isEmpty()) { View v = (View) c.getClientProperty(BasicHTML.propertyKey); if (v != null) { v.paint(g, textRect); } else { paintText(g, b, textRect, text); } } if (b.isFocusPainted() && b.hasFocus()) { // paint UI specific focus paintFocus(g, b, viewRect, textRect, iconRect); } } /** * Paints an icon of the current button. * * @param g an instance of {@code Graphics} * @param c a component * @param iconRect a bounding rectangle to render the icon */ protected void paintIcon(Graphics g, JComponent c, Rectangle iconRect) { AbstractButton b = (AbstractButton) c; ButtonModel model = b.getModel(); Icon icon = b.getIcon(); Icon tmpIcon = null; if (icon == null) { return; } Icon selectedIcon = null; /* the fallback icon should be based on the selected state */ if (model.isSelected()) { selectedIcon = b.getSelectedIcon(); if (selectedIcon != null) { icon = selectedIcon; } } if (!model.isEnabled()) { if (model.isSelected()) { tmpIcon = b.getDisabledSelectedIcon(); if (tmpIcon == null) { tmpIcon = selectedIcon; } } if (tmpIcon == null) { tmpIcon = b.getDisabledIcon(); } } else if (model.isPressed() && model.isArmed()) { tmpIcon = b.getPressedIcon(); if (tmpIcon != null) { // revert back to 0 offset clearTextShiftOffset(); } } else if (b.isRolloverEnabled() && model.isRollover()) { if (model.isSelected()) { tmpIcon = b.getRolloverSelectedIcon(); if (tmpIcon == null) { tmpIcon = selectedIcon; } } if (tmpIcon == null) { tmpIcon = b.getRolloverIcon(); } } if (tmpIcon != null) { icon = tmpIcon; } if (model.isPressed() && model.isArmed()) { icon.paintIcon(c, g, iconRect.x + getTextShiftOffset(), iconRect.y + getTextShiftOffset()); } else { icon.paintIcon(c, g, iconRect.x, iconRect.y); } } /** * Method which renders the text of the current button. * * As of Java 2 platform v 1.4 this method should not be used or overriden. * Use the paintText method which takes the AbstractButton argument. * * @param g an instance of {@code Graphics} * @param c a component * @param textRect a bounding rectangle to render the text * @param text a string to render */ protected void paintText(Graphics g, JComponent c, Rectangle textRect, String text) { AbstractButton b = (AbstractButton) c; ButtonModel model = b.getModel(); FontMetrics fm = SwingUtilities2.getFontMetrics(c, g); int mnemonicIndex = b.getDisplayedMnemonicIndex(); /* Draw the Text */ if (model.isEnabled()) { /*** paint the text normally */ g.setColor(b.getForeground()); SwingUtilities2.drawStringUnderlineCharAt(c, g, text, mnemonicIndex, textRect.x + getTextShiftOffset(), textRect.y + fm.getAscent() + getTextShiftOffset()); } else { /*** paint the text disabled ***/ g.setColor(b.getBackground().brighter()); SwingUtilities2.drawStringUnderlineCharAt(c, g, text, mnemonicIndex, textRect.x, textRect.y + fm.getAscent()); g.setColor(b.getBackground().darker()); SwingUtilities2.drawStringUnderlineCharAt(c, g, text, mnemonicIndex, textRect.x - 1, textRect.y + fm.getAscent() - 1); } } /** * Method which renders the text of the current button. * * @param g Graphics context * @param b Current button to render * @param textRect Bounding rectangle to render the text * @param text String to render * @since 1.4 */ protected void paintText(Graphics g, AbstractButton b, Rectangle textRect, String text) { paintText(g, (JComponent) b, textRect, text); } // Method signature defined here overriden in subclasses. // Perhaps this class should be abstract? /** * Paints a focused button. * * @param g an instance of {@code Graphics} * @param b an abstract button * @param viewRect a bounding rectangle to render the button * @param textRect a bounding rectangle to render the text * @param iconRect a bounding rectangle to render the icon */ protected void paintFocus(Graphics g, AbstractButton b, Rectangle viewRect, Rectangle textRect, Rectangle iconRect) { } /** * Paints a pressed button. * * @param g an instance of {@code Graphics} * @param b an abstract button */ protected void paintButtonPressed(Graphics g, AbstractButton b) { } /** * Clears the offset of the text. */ protected void clearTextShiftOffset() { this.shiftOffset = 0; } /** * Sets the offset of the text. */ protected void setTextShiftOffset() { this.shiftOffset = defaultTextShiftOffset; } /** * Returns the offset of the text. * * @return the offset of the text */ protected int getTextShiftOffset() { return shiftOffset; } // ******************************** // Layout Methods // ******************************** 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 getPreferredSize(JComponent c) { AbstractButton b = (AbstractButton) c; return BasicGraphicsUtils.getPreferredButtonSize(b, b.getIconTextGap()); } 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; } /** * Returns the baseline. * * @throws NullPointerException {@inheritDoc} * @throws IllegalArgumentException {@inheritDoc} * @see javax.swing.JComponent#getBaseline(int, int) * @since 1.6 */ public int getBaseline(JComponent c, int width, int height) { super.getBaseline(c, width, height); AbstractButton b = (AbstractButton) c; String text = b.getText(); if (text == null || text.isEmpty()) { return -1; } FontMetrics fm = b.getFontMetrics(b.getFont()); layout(b, fm, width, height); return BasicHTML.getBaseline(b, textRect.y, fm.getAscent(), textRect.width, textRect.height); } /** * Returns an enum indicating how the baseline of the component * changes as the size changes. * * @throws NullPointerException {@inheritDoc} * @see javax.swing.JComponent#getBaseline(int, int) * @since 1.6 */ public Component.BaselineResizeBehavior getBaselineResizeBehavior(JComponent c) { super.getBaselineResizeBehavior(c); if (c.getClientProperty(BasicHTML.propertyKey) != null) { return Component.BaselineResizeBehavior.OTHER; } switch (((AbstractButton) c).getVerticalAlignment()) { case AbstractButton.TOP: return Component.BaselineResizeBehavior.CONSTANT_ASCENT; case AbstractButton.BOTTOM: return Component.BaselineResizeBehavior.CONSTANT_DESCENT; case AbstractButton.CENTER: return Component.BaselineResizeBehavior.CENTER_OFFSET; } return Component.BaselineResizeBehavior.OTHER; } private String layout(AbstractButton b, FontMetrics fm, int width, int height) { Insets i = b.getInsets(); viewRect.x = i.left; viewRect.y = i.top; viewRect.width = width - (i.right + viewRect.x); viewRect.height = height - (i.bottom + viewRect.y); textRect.x = textRect.y = textRect.width = textRect.height = 0; iconRect.x = iconRect.y = iconRect.width = iconRect.height = 0; // layout the text and icon return SwingUtilities.layoutCompoundLabel(b, fm, b.getText(), b.getIcon(), b.getVerticalAlignment(), b.getHorizontalAlignment(), b.getVerticalTextPosition(), b.getHorizontalTextPosition(), viewRect, iconRect, textRect, b.getText() == null ? 0 : b.getIconTextGap()); } /** * Returns the ButtonListener for the passed in Button, or null if one * could not be found. */ private BasicButtonListener getButtonListener(AbstractButton b) { MouseMotionListener[] listeners = b.getMouseMotionListeners(); if (listeners != null) { for (MouseMotionListener listener : listeners) { if (listener instanceof BasicButtonListener) { return (BasicButtonListener) listener; } } } return null; } }