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 * 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

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package javax.swing.plaf.synth;

import java.awt.*;

import java.beans.*;

import javax.swing.*;

import javax.swing.plaf.*;

import javax.swing.plaf.basic.*;

/**

 * Provides the Synth L&F UI delegate for

 * {@link javax.swing.JScrollBar}.

 *

 * @author Scott Violet

 * @since 1.7

 */

public class SynthScrollBarUI extends BasicScrollBarUI

                              implements PropertyChangeListener, SynthUI {

    private SynthStyle style;

    private SynthStyle thumbStyle;

    private SynthStyle trackStyle;

    private boolean validMinimumThumbSize;

    public static ComponentUI createUI(JComponent c)    {

        return new SynthScrollBarUI();

    }

    /**

     * @inheritDoc

     */

    @Override

    protected void installDefaults() {

        trackHighlight = NO_HIGHLIGHT;

        if (scrollbar.getLayout() == null ||

                     (scrollbar.getLayout() instanceof UIResource)) {

            scrollbar.setLayout(this);

        }

        configureScrollBarColors();

        updateStyle(scrollbar);

    }

    /**

     * @inheritDoc

     */

    @Override

    protected void configureScrollBarColors() {

    }

    private void updateStyle(JScrollBar c) {

        SynthStyle oldStyle = style;

        SynthContext context = getContext(c, ENABLED);

        style = SynthLookAndFeel.updateStyle(context, this);

        if (style != oldStyle) {

            scrollBarWidth = style.getInt(context,"ScrollBar.thumbHeight", 14);

            minimumThumbSize = (Dimension)style.get(context,

                                                "ScrollBar.minimumThumbSize");

            if (minimumThumbSize == null) {

                minimumThumbSize = new Dimension();

                validMinimumThumbSize = false;

            }

            else {

                validMinimumThumbSize = true;

            }

            maximumThumbSize = (Dimension)style.get(context,

                        "ScrollBar.maximumThumbSize");

            if (maximumThumbSize == null) {

                maximumThumbSize = new Dimension(4096, 4097);

            }

            incrGap = style.getInt(context, "ScrollBar.incrementButtonGap", 0);

            decrGap = style.getInt(context, "ScrollBar.decrementButtonGap", 0);

            // handle scaling for sizeVarients for special case components. The

            // key "JComponent.sizeVariant" scales for large/small/mini

            // components are based on Apples LAF

            String scaleKey = (String)scrollbar.getClientProperty(

                    "JComponent.sizeVariant");

            if (scaleKey != null){

                if ("large".equals(scaleKey)){

                    scrollBarWidth *= 1.15;

                    incrGap *= 1.15;

                    decrGap *= 1.15;

                } else if ("small".equals(scaleKey)){

                    scrollBarWidth *= 0.857;

                    incrGap *= 0.857;

                    decrGap *= 0.857;

                } else if ("mini".equals(scaleKey)){

                    scrollBarWidth *= 0.714;

                    incrGap *= 0.714;

                    decrGap *= 0.714;

                }

            }

            if (oldStyle != null) {

                uninstallKeyboardActions();

                installKeyboardActions();

            }

        }

        context.dispose();

        context = getContext(c, Region.SCROLL_BAR_TRACK, ENABLED);

        trackStyle = SynthLookAndFeel.updateStyle(context, this);

        context.dispose();

        context = getContext(c, Region.SCROLL_BAR_THUMB, ENABLED);

        thumbStyle = SynthLookAndFeel.updateStyle(context, this);

        context.dispose();

    }

    /**

     * @inheritDoc

     */

    @Override

    protected void installListeners() {

        super.installListeners();

        scrollbar.addPropertyChangeListener(this);

    }

    /**

     * @inheritDoc

     */

    @Override

    protected void uninstallListeners() {

        super.uninstallListeners();

        scrollbar.removePropertyChangeListener(this);

    }

    /**

     * @inheritDoc

     */

    @Override

    protected void uninstallDefaults(){

        SynthContext context = getContext(scrollbar, ENABLED);

        style.uninstallDefaults(context);

        context.dispose();

        style = null;

        context = getContext(scrollbar, Region.SCROLL_BAR_TRACK, ENABLED);

        trackStyle.uninstallDefaults(context);

        context.dispose();

        trackStyle = null;

        context = getContext(scrollbar, Region.SCROLL_BAR_THUMB, ENABLED);

        thumbStyle.uninstallDefaults(context);

        context.dispose();

        thumbStyle = null;

        super.uninstallDefaults();

    }

    /**

     * @inheritDoc

     */

    @Override

    public SynthContext getContext(JComponent c) {

        return getContext(c, SynthLookAndFeel.getComponentState(c));

    }

    private SynthContext getContext(JComponent c, int state) {

        return SynthContext.getContext(SynthContext.class, c,

                    SynthLookAndFeel.getRegion(c), style, state);

    }

    private SynthContext getContext(JComponent c, Region region) {

        return getContext(c, region, getComponentState(c, region));

    }

    private SynthContext getContext(JComponent c, Region region, int state) {

        SynthStyle style = trackStyle;

        if (region == Region.SCROLL_BAR_THUMB) {

            style = thumbStyle;

        }

        return SynthContext.getContext(SynthContext.class, c, region, style,

                                       state);

    }

    private int getComponentState(JComponent c, Region region) {

        if (region == Region.SCROLL_BAR_THUMB && isThumbRollover() &&

                                                 c.isEnabled()) {

            return MOUSE_OVER;

        }

        return SynthLookAndFeel.getComponentState(c);

    }

    /**

     * @inheritDoc

     */

    @Override

    public boolean getSupportsAbsolutePositioning() {

        SynthContext context = getContext(scrollbar);

        boolean value = style.getBoolean(context,

                      "ScrollBar.allowsAbsolutePositioning", false);

        context.dispose();

        return value;

    }

    /**

     * Notifies this UI delegate to repaint the specified component.

     * This method paints the component background, then calls

     * the {@link #paint(SynthContext,Graphics)} method.

     *

     * <p>In general, this method does not need to be overridden by subclasses.

     * All Look and Feel rendering code should reside in the {@code paint} method.

     *

     * @param g the {@code Graphics} object used for painting

     * @param c the component being painted

     * @see #paint(SynthContext,Graphics)

     */

    @Override

    public void update(Graphics g, JComponent c) {

        SynthContext context = getContext(c);

        SynthLookAndFeel.update(context, g);

        context.getPainter().paintScrollBarBackground(context,

                          g, 0, 0, c.getWidth(), c.getHeight(),

                          scrollbar.getOrientation());

        paint(context, g);

        context.dispose();

    }

    /**

     * Paints the specified component according to the Look and Feel.

     * <p>This method is not used by Synth Look and Feel.

     * Painting is handled by the {@link #paint(SynthContext,Graphics)} method.

     *

     * @param g the {@code Graphics} object used for painting

     * @param c the component being painted

     * @see #paint(SynthContext,Graphics)

     */

    @Override

    public void paint(Graphics g, JComponent c) {

        SynthContext context = getContext(c);

        paint(context, g);

        context.dispose();

    }

    /**

     * Paints the specified component.

     *

     * @param context context for the component being painted

     * @param g the {@code Graphics} object used for painting

     * @see #update(Graphics,JComponent)

     */

    protected void paint(SynthContext context, Graphics g) {

        SynthContext subcontext = getContext(scrollbar,

                                             Region.SCROLL_BAR_TRACK);

        paintTrack(subcontext, g, getTrackBounds());

        subcontext.dispose();

        subcontext = getContext(scrollbar, Region.SCROLL_BAR_THUMB);

        paintThumb(subcontext, g, getThumbBounds());

        subcontext.dispose();

    }

    /**

     * @inheritDoc

     */

    @Override

    public void paintBorder(SynthContext context, Graphics g, int x,

                            int y, int w, int h) {

        context.getPainter().paintScrollBarBorder(context, g, x, y, w, h,

                                                  scrollbar.getOrientation());

    }

    /**

     * Paints the scrollbar track.

     *

     * @param context context for the component being painted

     * @param g {@code Graphics} object used for painting

     * @param trackBounds bounding box for the track

     */

    protected void paintTrack(SynthContext context, Graphics g,

                              Rectangle trackBounds) {

        SynthLookAndFeel.updateSubregion(context, g, trackBounds);

        context.getPainter().paintScrollBarTrackBackground(context, g, trackBounds.x,

                        trackBounds.y, trackBounds.width, trackBounds.height,

                        scrollbar.getOrientation());

        context.getPainter().paintScrollBarTrackBorder(context, g, trackBounds.x,

                        trackBounds.y, trackBounds.width, trackBounds.height,

                        scrollbar.getOrientation());

    }

    /**

     * Paints the scrollbar thumb.

     *

     * @param context context for the component being painted

     * @param g {@code Graphics} object used for painting

     * @param thumbBounds bounding box for the thumb

     */

    protected void paintThumb(SynthContext context, Graphics g,

                              Rectangle thumbBounds) {

        SynthLookAndFeel.updateSubregion(context, g, thumbBounds);

        int orientation = scrollbar.getOrientation();

        context.getPainter().paintScrollBarThumbBackground(context, g, thumbBounds.x,

                        thumbBounds.y, thumbBounds.width, thumbBounds.height,

                        orientation);

        context.getPainter().paintScrollBarThumbBorder(context, g, thumbBounds.x,

                        thumbBounds.y, thumbBounds.width, thumbBounds.height,

                        orientation);

    }

    /**

     * A vertical scrollbar's preferred width is the maximum of

     * preferred widths of the (non <code>null</code>)

     * increment/decrement buttons,

     * and the minimum width of the thumb. The preferred height is the

     * sum of the preferred heights of the same parts.  The basis for

     * the preferred size of a horizontal scrollbar is similar.

     * <p>

     * The <code>preferredSize</code> is only computed once, subsequent

     * calls to this method just return a cached size.

     *

     * @param c the <code>JScrollBar</code> that's delegating this method to us

     * @return the preferred size of a Basic JScrollBar

     * @see #getMaximumSize

     * @see #getMinimumSize

     */

    @Override

    public Dimension getPreferredSize(JComponent c) {

        Insets insets = c.getInsets();

        return (scrollbar.getOrientation() == JScrollBar.VERTICAL)

            ? new Dimension(scrollBarWidth + insets.left + insets.right, 48)

            : new Dimension(48, scrollBarWidth + insets.top + insets.bottom);

    }

    /**

     * @inheritDoc

     */

    @Override

    protected Dimension getMinimumThumbSize() {

        if (!validMinimumThumbSize) {

            if (scrollbar.getOrientation() == JScrollBar.VERTICAL) {

                minimumThumbSize.width = scrollBarWidth;

                minimumThumbSize.height = 7;

            } else {

                minimumThumbSize.width = 7;

                minimumThumbSize.height = scrollBarWidth;

            }

        }

        return minimumThumbSize;

    }

    /**

     * @inheritDoc

     */

    @Override

    protected JButton createDecreaseButton(int orientation)  {

        SynthArrowButton synthArrowButton = new SynthArrowButton(orientation) {

            @Override

            public boolean contains(int x, int y) {

                if (decrGap < 0) { //there is an overlap between the track and button

                    int width = getWidth();

                    int height = getHeight();

                    if (scrollbar.getOrientation() == JScrollBar.VERTICAL) {

                        //adjust the height by decrGap

                        //Note: decrGap is negative!

                        height += decrGap;

                    } else {

                        //adjust the width by decrGap

                        //Note: decrGap is negative!

                        width += decrGap;

                    }

                    return (x >= 0) && (x < width) && (y >= 0) && (y < height);

                }

                return super.contains(x, y);

            }

        };

        synthArrowButton.setName("ScrollBar.button");

        return synthArrowButton;

    }

    /**

     * @inheritDoc

     */

    @Override

    protected JButton createIncreaseButton(int orientation)  {

        SynthArrowButton synthArrowButton = new SynthArrowButton(orientation) {

            @Override

            public boolean contains(int x, int y) {

                if (incrGap < 0) { //there is an overlap between the track and button

                    int width = getWidth();

                    int height = getHeight();

                    if (scrollbar.getOrientation() == JScrollBar.VERTICAL) {

                        //adjust the height and y by incrGap

                        //Note: incrGap is negative!

                        height += incrGap;

                        y += incrGap;

                    } else {

                        //adjust the width and x by incrGap

                        //Note: incrGap is negative!

                        width += incrGap;

                        x += incrGap;

                    }

                    return (x >= 0) && (x < width) && (y >= 0) && (y < height);

                }

                return super.contains(x, y);

            }

        };

        synthArrowButton.setName("ScrollBar.button");

        return synthArrowButton;

    }

    /**

     * @inheritDoc

     */

    @Override

    protected void setThumbRollover(boolean active) {

        if (isThumbRollover() != active) {

            scrollbar.repaint(getThumbBounds());

            super.setThumbRollover(active);

        }

    }

    private void updateButtonDirections() {

        int orient = scrollbar.getOrientation();

        if (scrollbar.getComponentOrientation().isLeftToRight()) {

            ((SynthArrowButton)incrButton).setDirection(

                        orient == HORIZONTAL? EAST : SOUTH);

            ((SynthArrowButton)decrButton).setDirection(

                        orient == HORIZONTAL? WEST : NORTH);

        }

        else {

            ((SynthArrowButton)incrButton).setDirection(

                        orient == HORIZONTAL? WEST : SOUTH);

            ((SynthArrowButton)decrButton).setDirection(

                        orient == HORIZONTAL ? EAST : NORTH);

        }

    }

    //

    // PropertyChangeListener

    //

    public void propertyChange(PropertyChangeEvent e) {

        String propertyName = e.getPropertyName();

        if (SynthLookAndFeel.shouldUpdateStyle(e)) {

            updateStyle((JScrollBar)e.getSource());

        }

        if ("orientation" == propertyName) {

            updateButtonDirections();

        }

        else if ("componentOrientation" == propertyName) {

            updateButtonDirections();

        }

    }

}