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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.*;
import sun.swing.plaf.synth.SynthUI;


Synth's ScrollBarUI.
Author:Scott Violet
/** * Synth's ScrollBarUI. * * @author Scott Violet */
class SynthScrollBarUI extends BasicScrollBarUI implements PropertyChangeListener, SynthUI { private SynthStyle style; private SynthStyle thumbStyle; private SynthStyle trackStyle; private boolean validMinimumThumbSize; private int scrollBarWidth; //These two variables should be removed when the corrosponding ones in BasicScrollBarUI are made protected private int incrGap; private int decrGap; public static ComponentUI createUI(JComponent c) { return new SynthScrollBarUI(); } protected void installDefaults() { //NOTE: This next line of code was added because, since incrGap and decrGap in //BasicScrollBarUI are private, I need to have some way of updating them. //This is an incomplete solution (since it implies that the incrGap and decrGap //are set once, and not reset per state. Probably ok, but not always ok). //This line of code should be removed at the same time that incrGap and //decrGap are removed and made protected in the super class. super.installDefaults(); trackHighlight = NO_HIGHLIGHT; if (scrollbar.getLayout() == null || (scrollbar.getLayout() instanceof UIResource)) { scrollbar.setLayout(this); } updateStyle(scrollbar); } 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(); } protected void installListeners() { super.installListeners(); scrollbar.addPropertyChangeListener(this); } protected void uninstallListeners() { super.uninstallListeners(); scrollbar.removePropertyChangeListener(this); } 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(); } public SynthContext getContext(JComponent c) { return getContext(c, getComponentState(c)); } private SynthContext getContext(JComponent c, int state) { return SynthContext.getContext(SynthContext.class, c, SynthLookAndFeel.getRegion(c), style, state); } private Region getRegion(JComponent c) { return SynthLookAndFeel.getRegion(c); } private int getComponentState(JComponent c) { return SynthLookAndFeel.getComponentState(c); } 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); } public boolean getSupportsAbsolutePositioning() { SynthContext context = getContext(scrollbar); boolean value = style.getBoolean(context, "ScrollBar.allowsAbsolutePositioning", false); context.dispose(); return value; } 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(); } public void paint(Graphics g, JComponent c) { SynthContext context = getContext(c); paint(context, g); context.dispose(); } 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(); } 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()); } protected void paintTrack(SynthContext ss, Graphics g, Rectangle trackBounds) { SynthLookAndFeel.updateSubregion(ss, g, trackBounds); ss.getPainter().paintScrollBarTrackBackground(ss, g, trackBounds.x, trackBounds.y, trackBounds.width, trackBounds.height, scrollbar.getOrientation()); ss.getPainter().paintScrollBarTrackBorder(ss, g, trackBounds.x, trackBounds.y, trackBounds.width, trackBounds.height, scrollbar.getOrientation()); } protected void paintThumb(SynthContext ss, Graphics g, Rectangle thumbBounds) { SynthLookAndFeel.updateSubregion(ss, g, thumbBounds); int orientation = scrollbar.getOrientation(); ss.getPainter().paintScrollBarThumbBackground(ss, g, thumbBounds.x, thumbBounds.y, thumbBounds.width, thumbBounds.height, orientation); ss.getPainter().paintScrollBarThumbBorder(ss, 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 */
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); } 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; } 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; } 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; } 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(); } } }