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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 *
 * 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,
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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 JScrollBar. 
Author:Scott Violet
Since:1.7
/**
 * 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;

    
Constructs a SynthScrollBarUI. 
/**
     *
     * Constructs a {@code SynthScrollBarUI}.
     */
    public SynthScrollBarUI() {}

    
Returns a UI.

Params:
  • c – a component
Returns:a UI
/**
     * Returns a UI.
     * @return a UI
     * @param c a component
     */
    public static ComponentUI createUI(JComponent c)    {
        return new SynthScrollBarUI();
    }

    
{@inheritDoc}

/**
     * {@inheritDoc}
     */
    @Override
    protected void installDefaults() {
        super.installDefaults();
        trackHighlight = NO_HIGHLIGHT;
        if (scrollbar.getLayout() == null ||
                     (scrollbar.getLayout() instanceof UIResource)) {
            scrollbar.setLayout(this);
        }
        configureScrollBarColors();
        updateStyle(scrollbar);
    }

    
{@inheritDoc}

/**
     * {@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 = getContext(c, Region.SCROLL_BAR_TRACK, ENABLED);
        trackStyle = SynthLookAndFeel.updateStyle(context, this);

        context = getContext(c, Region.SCROLL_BAR_THUMB, ENABLED);
        thumbStyle = SynthLookAndFeel.updateStyle(context, this);
    }

    
{@inheritDoc}

/**
     * {@inheritDoc}
     */
    @Override
    protected void installListeners() {
        super.installListeners();
        scrollbar.addPropertyChangeListener(this);
    }

    
{@inheritDoc}

/**
     * {@inheritDoc}
     */
    @Override
    protected void uninstallListeners() {
        super.uninstallListeners();
        scrollbar.removePropertyChangeListener(this);
    }

    
{@inheritDoc}

/**
     * {@inheritDoc}
     */
    @Override
    protected void uninstallDefaults(){
        SynthContext context = getContext(scrollbar, ENABLED);
        style.uninstallDefaults(context);
        style = null;

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

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

        super.uninstallDefaults();
    }

    
{@inheritDoc}

/**
     * {@inheritDoc}
     */
    @Override
    public SynthContext getContext(JComponent c) {
        return getContext(c, SynthLookAndFeel.getComponentState(c));
    }

    private SynthContext getContext(JComponent c, int state) {
        return SynthContext.getContext(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(c, region, style, state);
    }

    private int getComponentState(JComponent c, Region region) {
        if (region == Region.SCROLL_BAR_THUMB && c.isEnabled()) {
            if (isDragging) {
                return PRESSED;
            } else if (isThumbRollover()) {
                return MOUSE_OVER;
            }
        }
        return SynthLookAndFeel.getComponentState(c);
    }

    
{@inheritDoc}

/**
     * {@inheritDoc}
     */
    @Override
    public boolean getSupportsAbsolutePositioning() {
        SynthContext context = getContext(scrollbar);
        boolean value = style.getBoolean(context,
                      "ScrollBar.allowsAbsolutePositioning", false);
        return value;
    }

    
Notifies this UI delegate to repaint the specified component. This method paints the component background, then calls the paint(SynthContext, Graphics) method. 
In general, this method does not need to be overridden by subclasses. All Look and Feel rendering code should reside in the paint method. 
Params:
  • g – the Graphics object used for painting
  • c – the component being painted
See Also:
/**
     * 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);
    }

    
Paints the specified component according to the Look and Feel.

This method is not used by Synth Look and Feel. Painting is handled by the paint(SynthContext, Graphics) method. 
Params:
  • g – the Graphics object used for painting
  • c – the component being painted
See Also:
/**
     * 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);
    }

    
Paints the specified component.

Params:
  • context – context for the component being painted
  • g – the Graphics object used for painting
See Also:
/**
     * 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 = getContext(scrollbar, Region.SCROLL_BAR_THUMB);
        paintThumb(subcontext, g, getThumbBounds());
    }

    
{@inheritDoc}

/**
     * {@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.

Params:
  • context – context for the component being painted
  • g – Graphics object used for painting
  • trackBounds – bounding box for the track
/**
     * 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.

Params:
  • context – context for the component being painted
  • g – Graphics object used for painting
  • thumbBounds – bounding box for the thumb
/**
     * 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 null)
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.


The preferredSize is only computed once, subsequent
calls to this method just return a cached size.

Params:
  • c – the JScrollBar that's delegating this method to us
See Also:
Returns:the preferred size of a Basic JScrollBar
/**
     * 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}

/**
     * {@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}

/**
     * {@inheritDoc}
     */
    @Override
    protected JButton createDecreaseButton(int orientation)  {
        @SuppressWarnings("serial") // anonymous class
        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}

/**
     * {@inheritDoc}
     */
    @Override
    protected JButton createIncreaseButton(int orientation)  {
        @SuppressWarnings("serial") // anonymous class
        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}

/**
     * {@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();
        }
    }
}