ComboCellRenderer.java

/*
 * Copyright (c) 2008, 2015 , Oracle. All rights reserved.
 *
 * This software is the proprietary information of Oracle Corporation.
 * Use is subject to license terms.
 */
package org.eclipse.persistence.tools.workbench.uitools.swing;

import java.awt.Component;
import java.awt.Image;

import javax.swing.GrayFilter;
import javax.swing.ImageIcon;
import javax.swing.JLabel;
import javax.swing.JList;
import javax.swing.ListCellRenderer;
import javax.swing.UIManager;
import javax.swing.plaf.UIResource;

import org.eclipse.persistence.tools.workbench.uitools.cell.CellRendererAdapter;

/**
 * This renderer is responsible to delegate to the encapsulated renderer
 * (which was the renderer set by the UI delegate) the task to render the
 * label based on the look and feel and then the <code>CellRendererAdapter</code>
 * is used to format the text, icon, tooltip and accessible name.
 *
 * @version 11.0.0
 * @since 11.0.0
 * @author Pascal Filion
 */
@SuppressWarnings("nls")
final class ComboCellRenderer implements ListCellRenderer,
                                         UIResource
{
    /**
     * The <code>ListCellRenderer</code> set by the UI delegate that will
     * return the actual <code>Component</code>
     */
    final ListCellRenderer cellRenderer;

    /**
     * The adapter used to update the text, icon, tooltip and accessible name.
     */
    final CellRendererAdapter cellRendererAdapter;

    /**
     * The object used as the prototype value, which is used to speed up the
     * calculation of the widget.
     */
    private final Component prototypeRenderer;

    /**
     * Creates a new <code>ListCellRenderer</code>.
     *
     * @param cellRenderer The <code>ListCellRenderer</code> set by the UI
     * delegate that will return the actual <code>Component</code>
     * @param cellRendererAdapter The adapter used to update the text, icon,
     * tooltip and accessible name
     * @param prototypeRenderer
     */
    ComboCellRenderer(ListCellRenderer cellRenderer,
                         CellRendererAdapter cellRendererAdapter,
                         Component prototypeRenderer)
    {
        super();

        this.cellRenderer        = cellRenderer;
        this.prototypeRenderer   = prototypeRenderer;
        this.cellRendererAdapter = cellRendererAdapter;
    }

    /**
     * {@inheritDoc}
     */
    public Component getListCellRendererComponent(JList list,
                                                  Object value,
                                                  int index,
                                                  boolean selected,
                                                  boolean cellHasFocus)
    {
        // Don't need to format the cell, use the prototype renderer directly
        if (value == prototypeRenderer)
        {
            return prototypeRenderer;
        }

        // This will allow the look and feel to set anything in order to
        // reflect the native OS
        JLabel renderer = (JLabel) cellRenderer.getListCellRendererComponent
        (
            list,
            null,
            index,
            selected,
            cellHasFocus
        );

        renderer.setEnabled(list.isEnabled());

        // Update the renderer's properties by converting the value to
        // something displayable (text, icon, tooltip)
        updateRenderer(renderer, value);

        // If the list does not have the focus, show the selected cell has
        // "partially" selected
        if (selected         &&
            !list.hasFocus() &&
             list.isFocusable())
        {
            renderer.setForeground(list.getForeground());
            renderer.setBackground(UIManager.getColor("Panel.background"));
        }

        // Grey out the icon
        if (!list.isEnabled()                  &&
            renderer.getIcon()         != null &&
            renderer.getDisabledIcon() == null &&
            renderer.getIcon() instanceof ImageIcon)
        {
            ImageIcon icon = (ImageIcon) renderer.getIcon();
            Image image = GrayFilter.createDisabledImage(icon.getImage());
            renderer.setIcon(new ImageIcon(image));
        }

        return renderer;
    }

    private void updateRenderer(JLabel renderer, Object value)
    {
        renderer.setText(cellRendererAdapter.buildText(value));
        renderer.setIcon(cellRendererAdapter.buildIcon(value));
        renderer.setToolTipText(cellRendererAdapter.buildToolTipText(value));
        renderer.getAccessibleContext().setAccessibleName(cellRendererAdapter.buildAccessibleName(value));
    }
}