basicsliderui.java

java1.6众多例子参考

/*
 * @(#)BasicSliderUI.java	1.108 08/05/29
 *
 * Copyright 2006 Sun Microsystems, Inc. All rights reserved.
 * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */

package javax.swing.plaf.basic;

import java.awt.Component;
import java.awt.Container;
import java.awt.Adjustable;
import java.awt.event.*;
import java.awt.FontMetrics;
import java.awt.Graphics;
import java.awt.Dimension;
import java.awt.Rectangle;
import java.awt.Point;
import java.awt.Insets;
import java.awt.Color;
import java.awt.IllegalComponentStateException;
import java.awt.Polygon;
import java.beans.*;
import java.util.Dictionary;
import java.util.Enumeration;

import javax.swing.border.AbstractBorder;

import javax.swing.*;
import javax.swing.event.*;
import javax.swing.plaf.*;
import sun.swing.DefaultLookup;
import sun.swing.UIAction;


/**
 * A Basic L&F implementation of SliderUI.
 *
 * @version 1.108 05/29/08
 * @author Tom Santos
 */
public class BasicSliderUI extends SliderUI{
    // Old actions forward to an instance of this.
    private static final Actions SHARED_ACTION = new Actions();

    public static final int POSITIVE_SCROLL = +1;
    public static final int NEGATIVE_SCROLL = -1;
    public static final int MIN_SCROLL = -2;
    public static final int MAX_SCROLL = +2;

    protected Timer scrollTimer;
    protected JSlider slider;

    protected Insets focusInsets = null;
    protected Insets insetCache = null;
    protected boolean leftToRightCache = true;
    protected Rectangle focusRect = null;
    protected Rectangle contentRect = null;
    protected Rectangle labelRect = null;
    protected Rectangle tickRect = null;
    protected Rectangle trackRect = null;
    protected Rectangle thumbRect = null;

    protected int trackBuffer = 0;  // The distance that the track is from the side of the control

    private transient boolean isDragging;

    protected TrackListener trackListener;
    protected ChangeListener changeListener;
    protected ComponentListener componentListener;
    protected FocusListener focusListener;
    protected ScrollListener scrollListener;
    protected PropertyChangeListener propertyChangeListener;
    private Handler handler;

    // Colors
    private Color shadowColor;
    private Color highlightColor;
    private Color focusColor;

    /**
     * Whther or not sameLabelBaselines is up to date.
     */
    private boolean checkedLabelBaselines;
    /**
     * Whether or not all the entries in the labeltable have the same
     * baseline.
     */
    private boolean sameLabelBaselines;


    protected Color getShadowColor() {
        return shadowColor;
    }

    protected Color getHighlightColor() {
        return highlightColor;
    }

    protected Color getFocusColor() {
        return focusColor;
    }

    /**
     * Returns true if the user is dragging the slider.
     *
     * @return true if the user is dragging the slider
     * @since 1.5
     */
    protected boolean isDragging() {
        return isDragging;
    }

    /////////////////////////////////////////////////////////////////////////////
    // ComponentUI Interface Implementation methods
    /////////////////////////////////////////////////////////////////////////////
    public static ComponentUI createUI(JComponent b)    {
        return new BasicSliderUI((JSlider)b);
    }

    public BasicSliderUI(JSlider b)   {
    }

    public void installUI(JComponent c)   {
        slider = (JSlider) c;

        checkedLabelBaselines = false;

        slider.setEnabled(slider.isEnabled());
        LookAndFeel.installProperty(slider, "opaque", Boolean.TRUE);

        isDragging = false;
        trackListener = createTrackListener( slider );
        changeListener = createChangeListener( slider );
        componentListener = createComponentListener( slider );
        focusListener = createFocusListener( slider );
        scrollListener = createScrollListener( slider );
	propertyChangeListener = createPropertyChangeListener( slider );

	installDefaults( slider );
	installListeners( slider );
	installKeyboardActions( slider );

        scrollTimer = new Timer( 100, scrollListener );
        scrollTimer.setInitialDelay( 300 );   

	insetCache = slider.getInsets();
	leftToRightCache = BasicGraphicsUtils.isLeftToRight(slider);
	focusRect = new Rectangle();
	contentRect = new Rectangle();
	labelRect = new Rectangle();
	tickRect = new Rectangle();
	trackRect = new Rectangle();
	thumbRect = new Rectangle();

	calculateGeometry(); // This figures out where the labels, ticks, track, and thumb are.
    }   

    public void uninstallUI(JComponent c) {
        if ( c != slider )
            throw new IllegalComponentStateException(
                                                    this + " was asked to deinstall() " 
                                                    + c + " when it only knows about " 
                                                    + slider + ".");

        LookAndFeel.uninstallBorder(slider);

        scrollTimer.stop();
        scrollTimer = null;

	uninstallListeners( slider );
	uninstallKeyboardActions(slider);

	focusInsets = null;
	insetCache = null;
	leftToRightCache = true;
	focusRect = null;
	contentRect = null;
	labelRect = null;
	tickRect = null;
	trackRect = null;
        thumbRect = null;
        trackListener = null;
        changeListener = null;
        componentListener = null;
        focusListener = null;
        scrollListener = null;
	propertyChangeListener = null;
        slider = null;
    }

    protected void installDefaults( JSlider slider ) {
        LookAndFeel.installBorder(slider, "Slider.border");
        LookAndFeel.installColorsAndFont(slider, "Slider.background",
					 "Slider.foreground", "Slider.font");
        highlightColor = UIManager.getColor("Slider.highlight");

        shadowColor = UIManager.getColor("Slider.shadow");
        focusColor = UIManager.getColor("Slider.focus");

	focusInsets = (Insets)UIManager.get( "Slider.focusInsets" );
        // use default if missing so that BasicSliderUI can be used in other
        // LAFs like Nimbus
        if (focusInsets == null) focusInsets = new InsetsUIResource(2,2,2,2);
    }

    protected TrackListener createTrackListener(JSlider slider) {
        return new TrackListener();
    }

    protected ChangeListener createChangeListener(JSlider slider) {
        return getHandler();
    }

    protected ComponentListener createComponentListener(JSlider slider) {
        return getHandler();
    }

    protected FocusListener createFocusListener(JSlider slider) {
        return getHandler();
    }

    protected ScrollListener createScrollListener( JSlider slider ) {
        return new ScrollListener();
    }

    protected PropertyChangeListener createPropertyChangeListener(
            JSlider slider) {
        return getHandler();
    }

    private Handler getHandler() {
        if (handler == null) {
            handler = new Handler();
        }
        return handler;
    }

    protected void installListeners( JSlider slider ) {
        slider.addMouseListener(trackListener);
        slider.addMouseMotionListener(trackListener);
        slider.addFocusListener(focusListener);
        slider.addComponentListener(componentListener);
        slider.addPropertyChangeListener( propertyChangeListener );
        slider.getModel().addChangeListener(changeListener);
    }

    protected void uninstallListeners( JSlider slider ) {
        slider.removeMouseListener(trackListener);
        slider.removeMouseMotionListener(trackListener);
        slider.removeFocusListener(focusListener);
        slider.removeComponentListener(componentListener);
        slider.removePropertyChangeListener( propertyChangeListener );
        slider.getModel().removeChangeListener(changeListener);
        handler = null;
    }

    protected void installKeyboardActions( JSlider slider ) {
	InputMap km = getInputMap(JComponent.WHEN_FOCUSED, slider);
	SwingUtilities.replaceUIInputMap(slider, JComponent.WHEN_FOCUSED, km);
        LazyActionMap.installLazyActionMap(slider, BasicSliderUI.class,
                "Slider.actionMap");
    }

    InputMap getInputMap(int condition, JSlider slider) {
        if (condition == JComponent.WHEN_FOCUSED) {
            InputMap keyMap = (InputMap)DefaultLookup.get(slider, this,
                  "Slider.focusInputMap");
            InputMap rtlKeyMap;

            if (slider.getComponentOrientation().isLeftToRight() ||
                ((rtlKeyMap = (InputMap)DefaultLookup.get(slider, this,
                          "Slider.focusInputMap.RightToLeft")) == null)) {
                return keyMap;
            } else {
                rtlKeyMap.setParent(keyMap);
                return rtlKeyMap;
            }
        }
        return null;
    }

    /**
     * Populates ComboBox's actions.
     */
    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_INCREMENT));
        map.put(new Actions(Actions.MAX_SCROLL_INCREMENT));
    }

    protected void uninstallKeyboardActions( JSlider slider ) {
	SwingUtilities.replaceUIActionMap(slider, null);
	SwingUtilities.replaceUIInputMap(slider, JComponent.WHEN_FOCUSED,
					 null);
    }


    /**
     * 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);
        if (slider.getPaintLabels() && labelsHaveSameBaselines()) {
            FontMetrics metrics = slider.getFontMetrics(slider.getFont());
            Insets insets = slider.getInsets();
            Dimension thumbSize = getThumbSize();
	    if (slider.getOrientation() == JSlider.HORIZONTAL) {
                int tickLength = getTickLength();
                int contentHeight = height - insets.top - insets.bottom -
                    focusInsets.top - focusInsets.bottom;
                int thumbHeight = thumbSize.height;
                int centerSpacing = thumbHeight;
                if (slider.getPaintTicks()) {
                    centerSpacing += tickLength;
                }
                // Assume uniform labels.
                centerSpacing += getHeightOfTallestLabel();
                int trackY = insets.top + focusInsets.top +
                    (contentHeight - centerSpacing - 1) / 2;
                int trackHeight = thumbHeight;
                int tickY = trackY + trackHeight;
                int tickHeight = tickLength;
                if (!slider.getPaintTicks()) {
                    tickHeight = 0;
                }
                int labelY = tickY + tickHeight;
                return labelY + metrics.getAscent();
            }
            else { // vertical
                boolean inverted = slider.getInverted();
                Integer value = inverted ? getLowestValue() :
                                           getHighestValue();
                if (value != null) {
                    int thumbHeight = thumbSize.height;
                    int trackBuffer = Math.max(metrics.getHeight() / 2,
                                               thumbHeight / 2);
                    int contentY = focusInsets.top + insets.top;
                    int trackY = contentY + trackBuffer;
                    int trackHeight = height - focusInsets.top -
                        focusInsets.bottom - insets.top - insets.bottom -
                        trackBuffer - trackBuffer;
                    int yPosition = yPositionForValue(value, trackY,
                                                      trackHeight);
                    return yPosition - metrics.getHeight() / 2 +
                        metrics.getAscent();
                }
            }
        }
        return 0;
    }

    /**
     * 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);
        // NOTE: BasicSpinner really provides for CENTER_OFFSET, but
        // the default min/pref size is smaller than it should be
        // so that getBaseline() doesn't implement the contract
        // for CENTER_OFFSET as defined in Component.
        return Component.BaselineResizeBehavior.OTHER;
    }

    /**
     * Returns true if all the labels from the label table have the same
     * baseline.
     *