JDK8/Java8源码在线阅读
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* accompanied this code).
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package javax.swing.plaf.basic;
import sun.swing.DefaultLookup;
import sun.swing.UIAction;
import java.awt.*;
import java.awt.event.*;
import java.beans.*;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.plaf.*;
import static sun.swing.SwingUtilities2.drawHLine;
import static sun.swing.SwingUtilities2.drawRect;
import static sun.swing.SwingUtilities2.drawVLine;
/**
* Implementation of ScrollBarUI for the Basic Look and Feel
*
* @author Rich Schiavi
* @author David Kloba
* @author Hans Muller
*/
public class BasicScrollBarUI
extends ScrollBarUI implements LayoutManager, SwingConstants
{
private static final int POSITIVE_SCROLL = 1;
private static final int NEGATIVE_SCROLL = -1;
private static final int MIN_SCROLL = 2;
private static final int MAX_SCROLL = 3;
// NOTE: DO NOT use this field directly, SynthScrollBarUI assumes you'll
// call getMinimumThumbSize to access it.
protected Dimension minimumThumbSize;
protected Dimension maximumThumbSize;
protected Color thumbHighlightColor;
protected Color thumbLightShadowColor;
protected Color thumbDarkShadowColor;
protected Color thumbColor;
protected Color trackColor;
protected Color trackHighlightColor;
protected JScrollBar scrollbar;
protected JButton incrButton;
protected JButton decrButton;
protected boolean isDragging;
protected TrackListener trackListener;
protected ArrowButtonListener buttonListener;
protected ModelListener modelListener;
protected Rectangle thumbRect;
protected Rectangle trackRect;
protected int trackHighlight;
protected static final int NO_HIGHLIGHT = 0;
protected static final int DECREASE_HIGHLIGHT = 1;
protected static final int INCREASE_HIGHLIGHT = 2;
protected ScrollListener scrollListener;
protected PropertyChangeListener propertyChangeListener;
protected Timer scrollTimer;
private final static int scrollSpeedThrottle = 60; // delay in milli seconds
/** True indicates a middle click will absolutely position the
* scrollbar. */
private boolean supportsAbsolutePositioning;
/**
* Hint as to what width (when vertical) or height (when horizontal)
* should be.
*
* @since 1.7
*/
protected int scrollBarWidth;
private Handler handler;
private boolean thumbActive;
/**
* Determine whether scrollbar layout should use cached value or adjusted
* value returned by scrollbar's <code>getValue</code>.
*/
private boolean useCachedValue = false;
/**
* The scrollbar value is cached to save real value if the view is adjusted.
*/
private int scrollBarValue;
/**
* Distance between the increment button and the track. This may be a negative
* number. If negative, then an overlap between the button and track will occur,
* which is useful for shaped buttons.
*
* @since 1.7
*/
protected int incrGap;
/**
* Distance between the decrement button and the track. This may be a negative
* number. If negative, then an overlap between the button and track will occur,
* which is useful for shaped buttons.
*
* @since 1.7
*/
protected int decrGap;
static void loadActionMap(LazyActionMap map) {
map.put(new Actions(Actions.POSITIVE_UNIT_INCREMENT));
map.put(new Actions(Actions.POSITIVE_BLOCK_INCREMENT));
map.put(new Actions(Actions.NEGATIVE_UNIT_INCREMENT));
map.put(new Actions(Actions.NEGATIVE_BLOCK_INCREMENT));
map.put(new Actions(Actions.MIN_SCROLL));
map.put(new Actions(Actions.MAX_SCROLL));
}
public static ComponentUI createUI(JComponent c) {
return new BasicScrollBarUI();
}
protected void configureScrollBarColors()
{
LookAndFeel.installColors(scrollbar, "ScrollBar.background",
"ScrollBar.foreground");
thumbHighlightColor = UIManager.getColor("ScrollBar.thumbHighlight");
thumbLightShadowColor = UIManager.getColor("ScrollBar.thumbShadow");
thumbDarkShadowColor = UIManager.getColor("ScrollBar.thumbDarkShadow");
thumbColor = UIManager.getColor("ScrollBar.thumb");
trackColor = UIManager.getColor("ScrollBar.track");
trackHighlightColor = UIManager.getColor("ScrollBar.trackHighlight");
}
public void installUI(JComponent c) {
scrollbar = (JScrollBar)c;
thumbRect = new Rectangle(0, 0, 0, 0);
trackRect = new Rectangle(0, 0, 0, 0);
installDefaults();
installComponents();
installListeners();
installKeyboardActions();
}
public void uninstallUI(JComponent c) {
scrollbar = (JScrollBar)c;
uninstallListeners();
uninstallDefaults();
uninstallComponents();
uninstallKeyboardActions();
thumbRect = null;
scrollbar = null;
incrButton = null;
decrButton = null;
}
protected void installDefaults()
{
scrollBarWidth = UIManager.getInt("ScrollBar.width");
if (scrollBarWidth <= 0) {
scrollBarWidth = 16;
}
minimumThumbSize = (Dimension)UIManager.get("ScrollBar.minimumThumbSize");
maximumThumbSize = (Dimension)UIManager.get("ScrollBar.maximumThumbSize");
Boolean absB = (Boolean)UIManager.get("ScrollBar.allowsAbsolutePositioning");
supportsAbsolutePositioning = (absB != null) ? absB.booleanValue() :
false;
trackHighlight = NO_HIGHLIGHT;
if (scrollbar.getLayout() == null ||
(scrollbar.getLayout() instanceof UIResource)) {
scrollbar.setLayout(this);
}
configureScrollBarColors();
LookAndFeel.installBorder(scrollbar, "ScrollBar.border");
LookAndFeel.installProperty(scrollbar, "opaque", Boolean.TRUE);
scrollBarValue = scrollbar.getValue();
incrGap = UIManager.getInt("ScrollBar.incrementButtonGap");
decrGap = UIManager.getInt("ScrollBar.decrementButtonGap");
// TODO this can be removed when incrGap/decrGap become protected
// 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 *= 0.714;
} else if ("mini".equals(scaleKey)){
scrollBarWidth *= 0.714;
incrGap *= 0.714;
decrGap *= 0.714;
}
}
}
protected void installComponents(){
switch (scrollbar.getOrientation()) {
case JScrollBar.VERTICAL:
incrButton = createIncreaseButton(SOUTH);
decrButton = createDecreaseButton(NORTH);
break;
case JScrollBar.HORIZONTAL:
if (scrollbar.getComponentOrientation().isLeftToRight()) {
incrButton = createIncreaseButton(EAST);
decrButton = createDecreaseButton(WEST);
} else {
incrButton = createIncreaseButton(WEST);
decrButton = createDecreaseButton(EAST);
}
break;
}
scrollbar.add(incrButton);
scrollbar.add(decrButton);
// Force the children's enabled state to be updated.
scrollbar.setEnabled(scrollbar.isEnabled());
}
protected void uninstallComponents(){
scrollbar.remove(incrButton);
scrollbar.remove(decrButton);
}
protected void installListeners(){
trackListener = createTrackListener();
buttonListener = createArrowButtonListener();
modelListener = createModelListener();
propertyChangeListener = createPropertyChangeListener();
scrollbar.addMouseListener(trackListener);
scrollbar.addMouseMotionListener(trackListener);
scrollbar.getModel().addChangeListener(modelListener);
scrollbar.addPropertyChangeListener(propertyChangeListener);
scrollbar.addFocusListener(getHandler());
if (incrButton != null) {
incrButton.addMouseListener(buttonListener);
}
if (decrButton != null) {
decrButton.addMouseListener(buttonListener);
}
scrollListener = createScrollListener();
scrollTimer = new Timer(scrollSpeedThrottle, scrollListener);
scrollTimer.setInitialDelay(300); // default InitialDelay?
}
protected void installKeyboardActions(){
LazyActionMap.installLazyActionMap(scrollbar, BasicScrollBarUI.class,
"ScrollBar.actionMap");
InputMap inputMap = getInputMap(JComponent.WHEN_FOCUSED);
SwingUtilities.replaceUIInputMap(scrollbar, JComponent.WHEN_FOCUSED,
inputMap);
inputMap = getInputMap(JComponent.WHEN_ANCESTOR_OF_FOCUSED_COMPONENT);
SwingUtilities.replaceUIInputMap(scrollbar,
JComponent.WHEN_ANCESTOR_OF_FOCUSED_COMPONENT, inputMap);
}
protected void uninstallKeyboardActions(){
SwingUtilities.replaceUIInputMap(scrollbar, JComponent.WHEN_FOCUSED,
null);
SwingUtilities.replaceUIActionMap(scrollbar, null);
}
private InputMap getInputMap(int condition) {
if (condition == JComponent.WHEN_FOCUSED) {
InputMap keyMap = (InputMap)DefaultLookup.get(
scrollbar, this, "ScrollBar.focusInputMap");
InputMap rtlKeyMap;
if (scrollbar.getComponentOrientation().isLeftToRight() ||
((rtlKeyMap = (InputMap)DefaultLookup.get(scrollbar, this, "ScrollBar.focusInputMap.RightToLeft")) == null)) {
return keyMap;
} else {
rtlKeyMap.setParent(keyMap);
return rtlKeyMap;
}
}
else if (condition == JComponent.WHEN_ANCESTOR_OF_FOCUSED_COMPONENT) {
InputMap keyMap = (InputMap)DefaultLookup.get(
scrollbar, this, "ScrollBar.ancestorInputMap");
InputMap rtlKeyMap;
if (scrollbar.getComponentOrientation().isLeftToRight() ||
((rtlKeyMap = (InputMap)DefaultLookup.get(scrollbar, this, "ScrollBar.ancestorInputMap.RightToLeft")) == null)) {
return keyMap;
} else {
rtlKeyMap.setParent(keyMap);
return rtlKeyMap;
}
}
return null;
}
protected void uninstallListeners() {
scrollTimer.stop();
scrollTimer = null;
if (decrButton != null){
decrButton.removeMouseListener(buttonListener);
}
if (incrButton != null){
incrButton.removeMouseListener(buttonListener);
}
scrollbar.getModel().removeChangeListener(modelListener);
scrollbar.removeMouseListener(trackListener);
scrollbar.removeMouseMotionListener(trackListener);
scrollbar.removePropertyChangeListener(propertyChangeListener);
scrollbar.removeFocusListener(getHandler());
handler = null;
}
protected void uninstallDefaults(){
LookAndFeel.uninstallBorder(scrollbar);
if (scrollbar.getLayout() == this) {
scrollbar.setLayout(null);
}
}
private Handler getHandler() {
if (handler == null) {
handler = new Handler();
}
return handler;
}
protected TrackListener createTrackListener(){
return new TrackListener();
}
protected ArrowButtonListener createArrowButtonListener(){
return new ArrowButtonListener();
}
protected ModelListener createModelListener(){
return new ModelListener();
}
protected ScrollListener createScrollListener(){
return new ScrollListener();
}
protected PropertyChangeListener createPropertyChangeListener() {
return getHandler();
}
private void updateThumbState(int x, int y) {
Rectangle rect = getThumbBounds();
setThumbRollover(rect.contains(x, y));
}
/**
* Sets whether or not the mouse is currently over the thumb.
*
* @param active True indicates the thumb is currently active.
* @since 1.5
*/
protected void setThumbRollover(boolean active) {
if (thumbActive != active) {
thumbActive = active;
scrollbar.repaint(getThumbBounds());
}
}
/**
* Returns true if the mouse is currently over the thumb.
*
* @return true if the thumb is currently active
* @since 1.5
*/
public boolean isThumbRollover() {
return thumbActive;
}
public void paint(Graphics g, JComponent c) {
paintTrack(g, c, getTrackBounds());
Rectangle thumbBounds = getThumbBounds();
if (thumbBounds.intersects(g.getClipBounds())) {
paintThumb(g, c, thumbBounds);
}
}
/**
* 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) {
return (scrollbar.getOrientation() == JScrollBar.VERTICAL)
? new Dimension(scrollBarWidth, 48)
: new Dimension(48, scrollBarWidth);
}
/**
* @param c The JScrollBar that's delegating this method to us.
* @return new Dimension(Integer.MAX_VALUE, Integer.MAX_VALUE);
* @see #getMinimumSize
* @see #getPreferredSize
*/
public Dimension getMaximumSize(JComponent c) {
return new Dimension(Integer.MAX_VALUE, Integer.MAX_VALUE);
}
protected JButton createDecreaseButton(int orientation) {
return new BasicArrowButton(orientation,
UIManager.getColor("ScrollBar.thumb"),
UIManager.getColor("ScrollBar.thumbShadow"),
UIManager.getColor("ScrollBar.thumbDarkShadow"),
UIManager.getColor("ScrollBar.thumbHighlight"));
}
protected JButton createIncreaseButton(int orientation) {
return new BasicArrowButton(orientation,
UIManager.getColor("ScrollBar.thumb"),
UIManager.getColor("ScrollBar.thumbShadow"),
UIManager.getColor("ScrollBar.thumbDarkShadow"),
UIManager.getColor("ScrollBar.thumbHighlight"));
}
protected void paintDecreaseHighlight(Graphics g)
{
Insets insets = scrollbar.getInsets();
Rectangle thumbR = getThumbBounds();
g.setColor(trackHighlightColor);
if (scrollbar.getOrientation() == JScrollBar.VERTICAL) {
//paint the distance between the start of the track and top of the thumb
int x = insets.left;
int y = trackRect.y;
int w = scrollbar.getWidth() - (insets.left + insets.right);
int h = thumbR.y - y;
g.fillRect(x, y, w, h);
} else {
//if left-to-right, fill the area between the start of the track and
//the left edge of the thumb. If right-to-left, fill the area between
//the end of the thumb and end of the track.
int x, w;
if (scrollbar.getComponentOrientation().isLeftToRight()) {
x = trackRect.x;
w = thumbR.x - x;
} else {
x = thumbR.x + thumbR.width;
w = trackRect.x + trackRect.width - x;
}
int y = insets.top;
int h = scrollbar.getHeight() - (insets.top + insets.bottom);
g.fillRect(x, y, w, h);
}
}
protected void paintIncreaseHighlight(Graphics g)
{
Insets insets = scrollbar.getInsets();
Rectangle thumbR = getThumbBounds();
g.setColor(trackHighlightColor);
if (scrollbar.getOrientation() == JScrollBar.VERTICAL) {
//fill the area between the bottom of the thumb and the end of the track.
int x = insets.left;
int y = thumbR.y + thumbR.height;
int w = scrollbar.getWidth() - (insets.left + insets.right);
int h = trackRect.y + trackRect.height - y;
g.fillRect(x, y, w, h);
}
else {
//if left-to-right, fill the area between the right of the thumb and the
//end of the track. If right-to-left, then fill the area to the left of
//the thumb and the start of the track.
int x, w;
if (scrollbar.getComponentOrientation().isLeftToRight()) {
x = thumbR.x + thumbR.width;
w = trackRect.x + trackRect.width - x;
} else {
x = trackRect.x;
w = thumbR.x - x;
}
int y = insets.top;
int h = scrollbar.getHeight() - (insets.top + insets.bottom);
g.fillRect(x, y, w, h);
}
}
protected void paintTrack(Graphics g, JComponent c, Rectangle trackBounds)
{
g.setColor(trackColor);
g.fillRect(trackBounds.x, trackBounds.y, trackBounds.width, trackBounds.height);
if(trackHighlight == DECREASE_HIGHLIGHT) {
paintDecreaseHighlight(g);
}
else if(trackHighlight == INCREASE_HIGHLIGHT) {
paintIncreaseHighlight(g);
}
}
protected void paintThumb(Graphics g, JComponent c, Rectangle thumbBounds)
{
if(thumbBounds.isEmpty() || !scrollbar.isEnabled()) {
return;
}
int w = thumbBounds.width;
int h = thumbBounds.height;
g.translate(thumbBounds.x, thumbBounds.y);
g.setColor(thumbDarkShadowColor);
drawRect(g, 0, 0, w - 1, h - 1);
g.setColor(thumbColor);
g.fillRect(0, 0, w - 1, h - 1);
g.setColor(thumbHighlightColor);
drawVLine(g, 1, 1, h - 2);
drawHLine(g, 2, w - 3, 1);
g.setColor(thumbLightShadowColor);
drawHLine(g, 2, w - 2, h - 2);
drawVLine(g, w - 2, 1, h - 3);
g.translate(-thumbBounds.x, -thumbBounds.y);
}
/**
* Returns the smallest acceptable size for the thumb. If the scrollbar
* becomes so small that this size isn't available, the thumb will be
* hidden.
* <p>
* <b>Warning </b>: the value returned by this method should not be
* be modified, it's a shared static constant.
*
* @return The smallest acceptable size for the thumb.
* @see #getMaximumThumbSize
*/
protected Dimension getMinimumThumbSize() {
return minimumThumbSize;
}
/**
* Returns the largest acceptable size for the thumb. To create a fixed
* size thumb one make this method and <code>getMinimumThumbSize</code>
* return the same value.
* <p>
* <b>Warning </b>: the value returned by this method should not be
* be modified, it's a shared static constant.
*
* @return The largest acceptable size for the thumb.
* @see #getMinimumThumbSize
*/
protected Dimension getMaximumThumbSize() {
return maximumThumbSize;
}
/*
* LayoutManager Implementation
*/
public void addLayoutComponent(String name, Component child) {}
public void removeLayoutComponent(Component child) {}
public Dimension preferredLayoutSize(Container scrollbarContainer) {
return getPreferredSize((JComponent)scrollbarContainer);
}
public Dimension minimumLayoutSize(Container scrollbarContainer) {
return getMinimumSize((JComponent)scrollbarContainer);
}
private int getValue(JScrollBar sb) {
return (useCachedValue) ? scrollBarValue : sb.getValue();
}
protected void layoutVScrollbar(JScrollBar sb)
{
Dimension sbSize = sb.getSize();
Insets sbInsets = sb.getInsets();
/*
* Width and left edge of the buttons and thumb.
*/
int itemW = sbSize.width - (sbInsets.left + sbInsets.right);
int itemX = sbInsets.left;
/* Nominal locations of the buttons, assuming their preferred
* size will fit.
*/
boolean squareButtons = DefaultLookup.getBoolean(
scrollbar, this, "ScrollBar.squareButtons", false);
int decrButtonH = squareButtons ? itemW :
decrButton.getPreferredSize().height;
int decrButtonY = sbInsets.top;
int incrButtonH = squareButtons ? itemW :
incrButton.getPreferredSize().height;
int incrButtonY = sbSize.height - (sbInsets.bottom + incrButtonH);
/* The thumb must fit within the height left over after we
* subtract the preferredSize of the buttons and the insets
* and the gaps
*/
int sbInsetsH = sbInsets.top + sbInsets.bottom;
int sbButtonsH = decrButtonH + incrButtonH;
int gaps = decrGap + incrGap;
float trackH = sbSize.height - (sbInsetsH + sbButtonsH) - gaps;
/* Compute the height and origin of the thumb. The case
* where the thumb is at the bottom edge is handled specially
* to avoid numerical problems in computing thumbY. Enforce
* the thumbs min/max dimensions. If the thumb doesn't
* fit in the track (trackH) we'll hide it later.
*/
float min = sb.getMinimum();
float extent = sb.getVisibleAmount();
float range = sb.getMaximum() - min;
float value = getValue(sb);
int thumbH = (range <= 0)
? getMaximumThumbSize().height : (int)(trackH * (extent / range));
thumbH = Math.max(thumbH, getMinimumThumbSize().height);
thumbH = Math.min(thumbH, getMaximumThumbSize().height);
int thumbY = incrButtonY - incrGap - thumbH;
if (value < (sb.getMaximum() - sb.getVisibleAmount())) {
float thumbRange = trackH - thumbH;
thumbY = (int)(0.5f + (thumbRange * ((value - min) / (range - extent))));
thumbY += decrButtonY + decrButtonH + decrGap;
}
/* If the buttons don't fit, allocate half of the available
* space to each and move the lower one (incrButton) down.
*/
int sbAvailButtonH = (sbSize.height - sbInsetsH);
if (sbAvailButtonH < sbButtonsH) {
incrButtonH = decrButtonH = sbAvailButtonH / 2;
incrButtonY = sbSize.height - (sbInsets.bottom + incrButtonH);
}
decrButton.setBounds(itemX, decrButtonY, itemW, decrButtonH);
incrButton.setBounds(itemX, incrButtonY, itemW, incrButtonH);
/* Update the trackRect field.
*/
int itrackY = decrButtonY + decrButtonH + decrGap;
int itrackH = incrButtonY - incrGap - itrackY;
trackRect.setBounds(itemX, itrackY, itemW, itrackH);
/* If the thumb isn't going to fit, zero it's bounds. Otherwise
* make sure it fits between the buttons. Note that setting the
* thumbs bounds will cause a repaint.
*/
if(thumbH >= (int)trackH) {
if (UIManager.getBoolean("ScrollBar.alwaysShowThumb")) {
// This is used primarily for GTK L&F, which expands the
// thumb to fit the track when it would otherwise be hidden.
setThumbBounds(itemX, itrackY, itemW, itrackH);
} else {
// Other L&F's simply hide the thumb in this case.
setThumbBounds(0, 0, 0, 0);
}
}
else {
if ((thumbY + thumbH) > incrButtonY - incrGap) {
thumbY = incrButtonY - incrGap - thumbH;
}
if (thumbY < (decrButtonY + decrButtonH + decrGap)) {
thumbY = decrButtonY + decrButtonH + decrGap + 1;
}
setThumbBounds(itemX, thumbY, itemW, thumbH);
}
}
protected void layoutHScrollbar(JScrollBar sb)
{
Dimension sbSize = sb.getSize();
Insets sbInsets = sb.getInsets();
/* Height and top edge of the buttons and thumb.
*/
int itemH = sbSize.height - (sbInsets.top + sbInsets.bottom);
int itemY = sbInsets.top;
boolean ltr = sb.getComponentOrientation().isLeftToRight();
/* Nominal locations of the buttons, assuming their preferred
* size will fit.
*/
boolean squareButtons = DefaultLookup.getBoolean(
scrollbar, this, "ScrollBar.squareButtons", false);
int leftButtonW = squareButtons ? itemH :
decrButton.getPreferredSize().width;
int rightButtonW = squareButtons ? itemH :
incrButton.getPreferredSize().width;
if (!ltr) {
int temp = leftButtonW;
leftButtonW = rightButtonW;
rightButtonW = temp;
}
int leftButtonX = sbInsets.left;
int rightButtonX = sbSize.width - (sbInsets.right + rightButtonW);
int leftGap = ltr ? decrGap : incrGap;
int rightGap = ltr ? incrGap : decrGap;
/* The thumb must fit within the width left over after we
* subtract the preferredSize of the buttons and the insets
* and the gaps
*/
int sbInsetsW = sbInsets.left + sbInsets.right;
int sbButtonsW = leftButtonW + rightButtonW;
float trackW = sbSize.width - (sbInsetsW + sbButtonsW) - (leftGap + rightGap);
/* Compute the width and origin of the thumb. Enforce
* the thumbs min/max dimensions. The case where the thumb
* is at the right edge is handled specially to avoid numerical
* problems in computing thumbX. If the thumb doesn't
* fit in the track (trackH) we'll hide it later.
*/
float min = sb.getMinimum();
float max = sb.getMaximum();
float extent = sb.getVisibleAmount();
float range = max - min;
float value = getValue(sb);
int thumbW = (range <= 0)
? getMaximumThumbSize().width : (int)(trackW * (extent / range));
thumbW = Math.max(thumbW, getMinimumThumbSize().width);
thumbW = Math.min(thumbW, getMaximumThumbSize().width);
int thumbX = ltr ? rightButtonX - rightGap - thumbW : leftButtonX + leftButtonW + leftGap;
if (value < (max - sb.getVisibleAmount())) {
float thumbRange = trackW - thumbW;
if( ltr ) {
thumbX = (int)(0.5f + (thumbRange * ((value - min) / (range - extent))));
} else {
thumbX = (int)(0.5f + (thumbRange * ((max - extent - value) / (range - extent))));
}
thumbX += leftButtonX + leftButtonW + leftGap;
}
/* If the buttons don't fit, allocate half of the available
* space to each and move the right one over.
*/
int sbAvailButtonW = (sbSize.width - sbInsetsW);
if (sbAvailButtonW < sbButtonsW) {
rightButtonW = leftButtonW = sbAvailButtonW / 2;
rightButtonX = sbSize.width - (sbInsets.right + rightButtonW + rightGap);
}
(ltr ? decrButton : incrButton).setBounds(leftButtonX, itemY, leftButtonW, itemH);
(ltr ? incrButton : decrButton).setBounds(rightButtonX, itemY, rightButtonW, itemH);
/* Update the trackRect field.
*/
int itrackX = leftButtonX + leftButtonW + leftGap;
int itrackW = rightButtonX - rightGap - itrackX;
trackRect.setBounds(itrackX, itemY, itrackW, itemH);
/* Make sure the thumb fits between the buttons. Note
* that setting the thumbs bounds causes a repaint.
*/
if (thumbW >= (int)trackW) {
if (UIManager.getBoolean("ScrollBar.alwaysShowThumb")) {
// This is used primarily for GTK L&F, which expands the
// thumb to fit the track when it would otherwise be hidden.
setThumbBounds(itrackX, itemY, itrackW, itemH);
} else {
// Other L&F's simply hide the thumb in this case.
setThumbBounds(0, 0, 0, 0);
}
}
else {
if (thumbX + thumbW > rightButtonX - rightGap) {
thumbX = rightButtonX - rightGap - thumbW;
}
if (thumbX < leftButtonX + leftButtonW + leftGap) {
thumbX = leftButtonX + leftButtonW + leftGap + 1;
}
setThumbBounds(thumbX, itemY, thumbW, itemH);
}
}
public void layoutContainer(Container scrollbarContainer)
{
/* If the user is dragging the value, we'll assume that the
* scrollbars layout is OK modulo the thumb which is being
* handled by the dragging code.
*/
if (isDragging) {
return;
}
JScrollBar scrollbar = (JScrollBar)scrollbarContainer;
switch (scrollbar.getOrientation()) {
case JScrollBar.VERTICAL:
layoutVScrollbar(scrollbar);
break;
case JScrollBar.HORIZONTAL:
layoutHScrollbar(scrollbar);
break;
}
}
/**
* Set the bounds of the thumb and force a repaint that includes
* the old thumbBounds and the new one.
*
* @see #getThumbBounds
*/
protected void setThumbBounds(int x, int y, int width, int height)
{
/* If the thumbs bounds haven't changed, we're done.
*/
if ((thumbRect.x == x) &&
(thumbRect.y == y) &&
(thumbRect.width == width) &&
(thumbRect.height == height)) {
return;
}
/* Update thumbRect, and repaint the union of x,y,w,h and
* the old thumbRect.
*/
int minX = Math.min(x, thumbRect.x);
int minY = Math.min(y, thumbRect.y);
int maxX = Math.max(x + width, thumbRect.x + thumbRect.width);
int maxY = Math.max(y + height, thumbRect.y + thumbRect.height);
thumbRect.setBounds(x, y, width, height);
scrollbar.repaint(minX, minY, maxX - minX, maxY - minY);
// Once there is API to determine the mouse location this will need
// to be changed.
setThumbRollover(false);
}
/**
* Return the current size/location of the thumb.
* <p>
* <b>Warning </b>: the value returned by this method should not be
* be modified, it's a reference to the actual rectangle, not a copy.
*
* @return The current size/location of the thumb.
* @see #setThumbBounds
*/
protected Rectangle getThumbBounds() {
return thumbRect;
}
/**
* Returns the current bounds of the track, i.e. the space in between
* the increment and decrement buttons, less the insets. The value
* returned by this method is updated each time the scrollbar is
* laid out (validated).
* <p>
* <b>Warning </b>: the value returned by this method should not be
* be modified, it's a reference to the actual rectangle, not a copy.
*
* @return the current bounds of the scrollbar track
* @see #layoutContainer
*/
protected Rectangle getTrackBounds() {
return trackRect;
}
/*
* Method for scrolling by a block increment.
* Added for mouse wheel scrolling support, RFE 4202656.
*/
static void scrollByBlock(JScrollBar scrollbar, int direction) {
// This method is called from BasicScrollPaneUI to implement wheel
// scrolling, and also from scrollByBlock().
int oldValue = scrollbar.getValue();
int blockIncrement = scrollbar.getBlockIncrement(direction);
int delta = blockIncrement * ((direction > 0) ? +1 : -1);
int newValue = oldValue + delta;
// Check for overflow.
if (delta > 0 && newValue < oldValue) {
newValue = scrollbar.getMaximum();
}
else if (delta < 0 && newValue > oldValue) {
newValue = scrollbar.getMinimum();
}
scrollbar.setValue(newValue);
}
protected void scrollByBlock(int direction)
{
scrollByBlock(scrollbar, direction);
trackHighlight = direction > 0 ? INCREASE_HIGHLIGHT : DECREASE_HIGHLIGHT;
Rectangle dirtyRect = getTrackBounds();
scrollbar.repaint(dirtyRect.x, dirtyRect.y, dirtyRect.width, dirtyRect.height);
}
/*
* Method for scrolling by a unit increment.
* Added for mouse wheel scrolling support, RFE 4202656.
*
* If limitByBlock is set to true, the scrollbar will scroll at least 1
* unit increment, but will not scroll farther than the block increment.
* See BasicScrollPaneUI.Handler.mouseWheelMoved().
*/
static void scrollByUnits(JScrollBar scrollbar, int direction,
int units, boolean limitToBlock) {
// This method is called from BasicScrollPaneUI to implement wheel
// scrolling, as well as from scrollByUnit().
int delta;
int limit = -1;
if (limitToBlock) {
if (direction < 0) {
limit = scrollbar.getValue() -
scrollbar.getBlockIncrement(direction);
}
else {
limit = scrollbar.getValue() +
scrollbar.getBlockIncrement(direction);
}
}
for (int i=0; i<units; i++) {
if (direction > 0) {
delta = scrollbar.getUnitIncrement(direction);
}
else {
delta = -scrollbar.getUnitIncrement(direction);
}
int oldValue = scrollbar.getValue();
int newValue = oldValue + delta;
// Check for overflow.
if (delta > 0 && newValue < oldValue) {
newValue = scrollbar.getMaximum();
}
else if (delta < 0 && newValue > oldValue) {
newValue = scrollbar.getMinimum();
}
if (oldValue == newValue) {
break;
}
if (limitToBlock && i > 0) {
assert limit != -1;
if ((direction < 0 && newValue < limit) ||
(direction > 0 && newValue > limit)) {
break;
}
}
scrollbar.setValue(newValue);
}
}
protected void scrollByUnit(int direction) {
scrollByUnits(scrollbar, direction, 1, false);
}
/**
* Indicates whether the user can absolutely position the thumb with
* a mouse gesture (usually the middle mouse button).
*
* @return true if a mouse gesture can absolutely position the thumb
* @since 1.5
*/
public boolean getSupportsAbsolutePositioning() {
return supportsAbsolutePositioning;
}
/**
* A listener to listen for model changes.
*
*/
protected class ModelListener implements ChangeListener {
public void stateChanged(ChangeEvent e) {
if (!useCachedValue) {
scrollBarValue = scrollbar.getValue();
}
layoutContainer(scrollbar);
useCachedValue = false;
}
}
/**
* Track mouse drags.
*/
protected class TrackListener
extends MouseAdapter implements MouseMotionListener
{
protected transient int offset;
protected transient int currentMouseX, currentMouseY;
private transient int direction = +1;
public void mouseReleased(MouseEvent e)
{
if (isDragging) {
updateThumbState(e.getX(), e.getY());
}
if (SwingUtilities.isRightMouseButton(e) ||
(!getSupportsAbsolutePositioning() &&
SwingUtilities.isMiddleMouseButton(e)))
return;
if(!scrollbar.isEnabled())
return;
Rectangle r = getTrackBounds();
scrollbar.repaint(r.x, r.y, r.width, r.height);
trackHighlight = NO_HIGHLIGHT;
isDragging = false;
offset = 0;
scrollTimer.stop();
useCachedValue = true;
scrollbar.setValueIsAdjusting(false);
}
/**
* If the mouse is pressed above the "thumb" component
* then reduce the scrollbars value by one page ("page up"),
* otherwise increase it by one page. If there is no
* thumb then page up if the mouse is in the upper half
* of the track.
*/
public void mousePressed(MouseEvent e)
{
if (SwingUtilities.isRightMouseButton(e) ||
(!getSupportsAbsolutePositioning() &&
SwingUtilities.isMiddleMouseButton(e)))
return;
if(!scrollbar.isEnabled())
return;
if (!scrollbar.hasFocus() && scrollbar.isRequestFocusEnabled()) {
scrollbar.requestFocus();
}
useCachedValue = true;
scrollbar.setValueIsAdjusting(true);
currentMouseX = e.getX();
currentMouseY = e.getY();
// Clicked in the Thumb area?
if(getThumbBounds().contains(currentMouseX, currentMouseY)) {
switch (scrollbar.getOrientation()) {
case JScrollBar.VERTICAL:
offset = currentMouseY - getThumbBounds().y;
break;
case JScrollBar.HORIZONTAL:
offset = currentMouseX - getThumbBounds().x;
break;
}
isDragging = true;
return;
}
else if (getSupportsAbsolutePositioning() &&
SwingUtilities.isMiddleMouseButton(e)) {
switch (scrollbar.getOrientation()) {
case JScrollBar.VERTICAL:
offset = getThumbBounds().height / 2;
break;
case JScrollBar.HORIZONTAL:
offset = getThumbBounds().width / 2;
break;
}
isDragging = true;
setValueFrom(e);
return;
}
isDragging = false;
Dimension sbSize = scrollbar.getSize();
direction = +1;
switch (scrollbar.getOrientation()) {
case JScrollBar.VERTICAL:
if (getThumbBounds().isEmpty()) {
int scrollbarCenter = sbSize.height / 2;
direction = (currentMouseY < scrollbarCenter) ? -1 : +1;
} else {
int thumbY = getThumbBounds().y;
direction = (currentMouseY < thumbY) ? -1 : +1;
}
break;
case JScrollBar.HORIZONTAL:
if (getThumbBounds().isEmpty()) {
int scrollbarCenter = sbSize.width / 2;
direction = (currentMouseX < scrollbarCenter) ? -1 : +1;
} else {
int thumbX = getThumbBounds().x;
direction = (currentMouseX < thumbX) ? -1 : +1;
}
if (!scrollbar.getComponentOrientation().isLeftToRight()) {
direction = -direction;
}
break;
}
scrollByBlock(direction);
scrollTimer.stop();
scrollListener.setDirection(direction);
scrollListener.setScrollByBlock(true);
startScrollTimerIfNecessary();
}
/**
* Set the models value to the position of the thumb's top of Vertical
* scrollbar, or the left/right of Horizontal scrollbar in
* left-to-right/right-to-left scrollbar relative to the origin of the
* track.
*/
public void mouseDragged(MouseEvent e) {
if (SwingUtilities.isRightMouseButton(e) ||
(!getSupportsAbsolutePositioning() &&
SwingUtilities.isMiddleMouseButton(e)))
return;
if(!scrollbar.isEnabled() || getThumbBounds().isEmpty()) {
return;
}
if (isDragging) {
setValueFrom(e);
} else {
currentMouseX = e.getX();
currentMouseY = e.getY();
updateThumbState(currentMouseX, currentMouseY);
startScrollTimerIfNecessary();
}
}
private void setValueFrom(MouseEvent e) {
boolean active = isThumbRollover();
BoundedRangeModel model = scrollbar.getModel();
Rectangle thumbR = getThumbBounds();
float trackLength;
int thumbMin, thumbMax, thumbPos;
if (scrollbar.getOrientation() == JScrollBar.VERTICAL) {
thumbMin = trackRect.y;
thumbMax = trackRect.y + trackRect.height - thumbR.height;
thumbPos = Math.min(thumbMax, Math.max(thumbMin, (e.getY() - offset)));
setThumbBounds(thumbR.x, thumbPos, thumbR.width, thumbR.height);
trackLength = getTrackBounds().height;
}
else {
thumbMin = trackRect.x;
thumbMax = trackRect.x + trackRect.width - thumbR.width;
thumbPos = Math.min(thumbMax, Math.max(thumbMin, (e.getX() - offset)));
setThumbBounds(thumbPos, thumbR.y, thumbR.width, thumbR.height);
trackLength = getTrackBounds().width;
}
/* Set the scrollbars value. If the thumb has reached the end of
* the scrollbar, then just set the value to its maximum. Otherwise
* compute the value as accurately as possible.
*/
if (thumbPos == thumbMax) {
if (scrollbar.getOrientation() == JScrollBar.VERTICAL ||
scrollbar.getComponentOrientation().isLeftToRight()) {
scrollbar.setValue(model.getMaximum() - model.getExtent());
} else {
scrollbar.setValue(model.getMinimum());
}
}
else {
float valueMax = model.getMaximum() - model.getExtent();
float valueRange = valueMax - model.getMinimum();
float thumbValue = thumbPos - thumbMin;
float thumbRange = thumbMax - thumbMin;
int value;
if (scrollbar.getOrientation() == JScrollBar.VERTICAL ||
scrollbar.getComponentOrientation().isLeftToRight()) {
value = (int)(0.5 + ((thumbValue / thumbRange) * valueRange));
} else {
value = (int)(0.5 + (((thumbMax - thumbPos) / thumbRange) * valueRange));
}
useCachedValue = true;
scrollBarValue = value + model.getMinimum();
scrollbar.setValue(adjustValueIfNecessary(scrollBarValue));
}
setThumbRollover(active);
}
private int adjustValueIfNecessary(int value) {
if (scrollbar.getParent() instanceof JScrollPane) {
JScrollPane scrollpane = (JScrollPane)scrollbar.getParent();
JViewport viewport = scrollpane.getViewport();
Component view = viewport.getView();
if (view instanceof JList) {
JList list = (JList)view;
if (DefaultLookup.getBoolean(list, list.getUI(),
"List.lockToPositionOnScroll", false)) {
int adjustedValue = value;
int mode = list.getLayoutOrientation();
int orientation = scrollbar.getOrientation();
if (orientation == JScrollBar.VERTICAL && mode == JList.VERTICAL) {
int index = list.locationToIndex(new Point(0, value));
Rectangle rect = list.getCellBounds(index, index);
if (rect != null) {
adjustedValue = rect.y;
}
}
if (orientation == JScrollBar.HORIZONTAL &&
(mode == JList.VERTICAL_WRAP || mode == JList.HORIZONTAL_WRAP)) {
if (scrollpane.getComponentOrientation().isLeftToRight()) {
int index = list.locationToIndex(new Point(value, 0));
Rectangle rect = list.getCellBounds(index, index);
if (rect != null) {
adjustedValue = rect.x;
}
}
else {
Point loc = new Point(value, 0);
int extent = viewport.getExtentSize().width;
loc.x += extent - 1;
int index = list.locationToIndex(loc);
Rectangle rect = list.getCellBounds(index, index);
if (rect != null) {
adjustedValue = rect.x + rect.width - extent;
}
}
}
value = adjustedValue;
}
}
}
return value;
}
private void startScrollTimerIfNecessary() {
if (scrollTimer.isRunning()) {
return;
}
Rectangle tb = getThumbBounds();
switch (scrollbar.getOrientation()) {
case JScrollBar.VERTICAL:
if (direction > 0) {
if (tb.y + tb.height < trackListener.currentMouseY) {
scrollTimer.start();
}
} else if (tb.y > trackListener.currentMouseY) {
scrollTimer.start();
}
break;
case JScrollBar.HORIZONTAL:
if ((direction > 0 && isMouseAfterThumb())
|| (direction < 0 && isMouseBeforeThumb())) {
scrollTimer.start();
}
break;
}
}
public void mouseMoved(MouseEvent e) {
if (!isDragging) {
updateThumbState(e.getX(), e.getY());
}
}
/**
* Invoked when the mouse exits the scrollbar.
*
* @param e MouseEvent further describing the event
* @since 1.5
*/
public void mouseExited(MouseEvent e) {
if (!isDragging) {
setThumbRollover(false);
}
}
}
/**
* Listener for cursor keys.
*/
protected class ArrowButtonListener extends MouseAdapter
{
// Because we are handling both mousePressed and Actions
// we need to make sure we don't fire under both conditions.
// (keyfocus on scrollbars causes action without mousePress
boolean handledEvent;
public void mousePressed(MouseEvent e) {
if(!scrollbar.isEnabled()) { return; }
// not an unmodified left mouse button
//if(e.getModifiers() != InputEvent.BUTTON1_MASK) {return; }
if( ! SwingUtilities.isLeftMouseButton(e)) { return; }
int direction = (e.getSource() == incrButton) ? 1 : -1;
scrollByUnit(direction);
scrollTimer.stop();
scrollListener.setDirection(direction);
scrollListener.setScrollByBlock(false);
scrollTimer.start();
handledEvent = true;
if (!scrollbar.hasFocus() && scrollbar.isRequestFocusEnabled()) {
scrollbar.requestFocus();
}
}
public void mouseReleased(MouseEvent e) {
scrollTimer.stop();
handledEvent = false;
scrollbar.setValueIsAdjusting(false);
}
}
/**
* Listener for scrolling events initiated in the
* <code>ScrollPane</code>.
*/
protected class ScrollListener implements ActionListener
{
int direction = +1;
boolean useBlockIncrement;
public ScrollListener() {
direction = +1;
useBlockIncrement = false;
}
public ScrollListener(int dir, boolean block) {
direction = dir;
useBlockIncrement = block;
}
public void setDirection(int direction) { this.direction = direction; }
public void setScrollByBlock(boolean block) { this.useBlockIncrement = block; }
public void actionPerformed(ActionEvent e) {
if(useBlockIncrement) {
scrollByBlock(direction);
// Stop scrolling if the thumb catches up with the mouse
if(scrollbar.getOrientation() == JScrollBar.VERTICAL) {
if(direction > 0) {
if(getThumbBounds().y + getThumbBounds().height
>= trackListener.currentMouseY)
((Timer)e.getSource()).stop();
} else if(getThumbBounds().y <= trackListener.currentMouseY) {
((Timer)e.getSource()).stop();
}
} else {
if ((direction > 0 && !isMouseAfterThumb())
|| (direction < 0 && !isMouseBeforeThumb())) {
((Timer)e.getSource()).stop();
}
}
} else {
scrollByUnit(direction);
}
if(direction > 0
&& scrollbar.getValue()+scrollbar.getVisibleAmount()
>= scrollbar.getMaximum())
((Timer)e.getSource()).stop();
else if(direction < 0
&& scrollbar.getValue() <= scrollbar.getMinimum())
((Timer)e.getSource()).stop();
}
}
private boolean isMouseLeftOfThumb() {
return trackListener.currentMouseX < getThumbBounds().x;
}
private boolean isMouseRightOfThumb() {
Rectangle tb = getThumbBounds();
return trackListener.currentMouseX > tb.x + tb.width;
}
private boolean isMouseBeforeThumb() {
return scrollbar.getComponentOrientation().isLeftToRight()
? isMouseLeftOfThumb()
: isMouseRightOfThumb();
}
private boolean isMouseAfterThumb() {
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