https://openjdk.java.net/ 
/*
 * Copyright (c) 2002, 2013, Oracle and/or its affiliates. All rights reserved.
 * 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
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

package javax.swing.plaf.synth;

import java.beans.*;
import javax.swing.*;
import javax.swing.plaf.*;
import java.awt.*;



Provides the Synth L&F UI delegate for JViewport. 
Since:1.7
/**
 * Provides the Synth L&F UI delegate for
 * {@link javax.swing.JViewport}.
 *
 * @since 1.7
 */
public class SynthViewportUI extends ViewportUI
                             implements PropertyChangeListener, SynthUI {
    private SynthStyle style;

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

    
Creates a new UI object for the given component.

Params:
  • c – component to create UI object for
Returns:the UI object
/**
     * Creates a new UI object for the given component.
     *
     * @param c component to create UI object for
     * @return the UI object
     */
    public static ComponentUI createUI(JComponent c) {
        return new SynthViewportUI();
    }

    
{@inheritDoc}

/**
     * {@inheritDoc}
     */
    @Override
    public void installUI(JComponent c) {
        super.installUI(c);
        installDefaults(c);
        installListeners(c);
    }

    
{@inheritDoc}

/**
     * {@inheritDoc}
     */
    @Override
    public void uninstallUI(JComponent c) {
        super.uninstallUI(c);
        uninstallListeners(c);
        uninstallDefaults(c);
    }

    
Installs defaults for a viewport.

Params:
  • c – a JViewport object
/**
     * Installs defaults for a viewport.
     *
     * @param c a {@code JViewport} object
     */
    protected void installDefaults(JComponent c) {
        updateStyle(c);
    }

    private void updateStyle(JComponent c) {
        SynthContext context = getContext(c, ENABLED);

        // Note: JViewport is special cased as it does not allow for
        // a border to be set. JViewport.setBorder is overriden to throw
        // an IllegalArgumentException. Refer to SynthScrollPaneUI for
        // details of this.
        SynthStyle newStyle = SynthLookAndFeel.getStyle(context.getComponent(),
                                                        context.getRegion());
        SynthStyle oldStyle = context.getStyle();

        if (newStyle != oldStyle) {
            if (oldStyle != null) {
                oldStyle.uninstallDefaults(context);
            }
            context.setStyle(newStyle);
            newStyle.installDefaults(context);
        }
        this.style = newStyle;
    }

    
Installs listeners into the viewport.

Params:
  • c – a JViewport object
/**
     * Installs listeners into the viewport.
     *
     * @param c a {@code JViewport} object
     */
    protected void installListeners(JComponent c) {
        c.addPropertyChangeListener(this);
    }

    
Uninstalls listeners from the viewport.

Params:
  • c – a JViewport object
/**
     * Uninstalls listeners from the viewport.
     *
     * @param c a {@code JViewport} object
     */
    protected void uninstallListeners(JComponent c) {
        c.removePropertyChangeListener(this);
    }

    
Uninstalls defaults from a viewport.

Params:
  • c – a JViewport object
/**
     * Uninstalls defaults from a viewport.
     *
     * @param c a {@code JViewport} object
     */
    protected void uninstallDefaults(JComponent c) {
        SynthContext context = getContext(c, ENABLED);
        style.uninstallDefaults(context);
        style = null;
    }

    
{@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 Region getRegion(JComponent c) {
        return SynthLookAndFeel.getRegion(c);
    }

    
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().paintViewportBackground(context,
                          g, 0, 0, c.getWidth(), c.getHeight());
        paint(context, g);
    }

    
Paints the border. The method is never called, because the JViewport class does not support a border. This implementation does nothing. 
Params:
  • context – a component context
  • g – the Graphics to paint on
  • x – the X coordinate
  • y – the Y coordinate
  • w – width of the border
  • h – height of the border
/**
     * Paints the border. The method is never called,
     * because the {@code JViewport} class does not support a border.
     * This implementation does nothing.
     *
     * @param context a component context
     * @param g the {@code Graphics} to paint on
     * @param x the X coordinate
     * @param y the Y coordinate
     * @param w width of the border
     * @param h height of the border
     */
    @Override
    public void paintBorder(SynthContext context, Graphics g, int x,
                            int y, int w, int h) {
    }

    
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. This implementation does nothing.

Params:
  • context – context for the component being painted
  • g – the Graphics object used for painting
See Also:
/**
     * Paints the specified component. This implementation does nothing.
     *
     * @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) {
    }

    
{@inheritDoc}

/**
     * {@inheritDoc}
     */
    @Override
    public void propertyChange(PropertyChangeEvent e) {
        if (SynthLookAndFeel.shouldUpdateStyle(e)) {
            updateStyle((JComponent)e.getSource());
        }
    }
}