path: root/projects/net.wotonomy.ui.swing/src/main/java/net/wotonomy/ui/swing/components/IconCellRenderer.java

/*
Wotonomy: OpenStep design patterns for pure Java applications.
Copyright (C) 2000 Intersect Software Corporation

This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.

This library 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
Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public
License along with this library; if not, see http://www.gnu.org
*/

package net.wotonomy.ui.swing.components;

import java.awt.Color;
import java.awt.Component;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Insets;
import java.awt.Point;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.util.Enumeration;
import java.util.EventObject;
import java.util.Vector;

import javax.swing.Icon;
import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JLabel;
import javax.swing.JList;
import javax.swing.JPanel;
import javax.swing.JTable;
import javax.swing.JTree;
import javax.swing.ListCellRenderer;
import javax.swing.SwingUtilities;
import javax.swing.UIManager;
import javax.swing.border.Border;
import javax.swing.border.EmptyBorder;
import javax.swing.border.LineBorder;
import javax.swing.event.CellEditorListener;
import javax.swing.event.ChangeEvent;
import javax.swing.table.TableCellEditor;
import javax.swing.table.TableCellRenderer;
import javax.swing.tree.TreeCellEditor;
import javax.swing.tree.TreeCellRenderer;

/**
 * A cell renderer that displays icons in addition to text, and additionally is
 * an editor in case you want to click the icon to trigger some kind of action.
 * You probably should override both getStringForContext and getIconForContext
 * to achieve your desired results. To receive mouse clicks, set the same
 * instance of the renderer as the editor for the same component.<br>
 * <br>
 *
 * One notable addition is that this class is an action event broadcaster.
 * ActionEvents are broadcast when the mouse is clicked on the button with an
 * action event containing a user-configurable string that defaults to CLICKED.
 * <br>
 * <br>
 *
 * The renderer itself can be used as a JComponent if you need something like a
 * JLabel that allows you to click on the icon. You will want to call setIcon
 * and setText to configure the component since the renderer method would not be
 * called. (If you add an instance of the renderer to a container, you cannnot
 * use the same instance as an editor in a table, tree, or list.)
 *
 * @author michael@mpowers.net
 * @version $Revision: 904 $ $Date: 2006-02-18 18:19:05 -0500 (Sat, 18 Feb 2006)
 *          $
 */
public class IconCellRenderer extends JPanel implements TableCellRenderer, TableCellEditor, TreeCellRenderer,
		TreeCellEditor, ListCellRenderer, Runnable, ActionListener, MouseListener {
	public static final String CLICKED = "CLICKED";

	/**
	 * The panel that is re-used to render everything. This is returned by
	 * getRendererForContext.
	 */
	protected JPanel rendererPanel;
	protected JLabel rendererLabel;
	protected JButton rendererButton;

	/**
	 * The panel that is used to receive mouse clicks. It must be a different
	 * component from rendererPanel. This is returned by getEditorForContext.
	 */
	protected JPanel editorPanel;
	protected JLabel editorLabel;
	protected JButton editorButton;

	private Object lastKnownValue;
	private JComponent lastKnownComponent;

	// do as DefaultTableCellRenderer does
	private Border noFocusBorder;
	private Border treeFocusBorder;
	private Color unselectedForeground;
	private Color unselectedBackground;

	private Vector actionListeners;
	private String actionCommand;
	private Vector cellEditorListeners;

	private boolean editable;
	private boolean clickable;

	/**
	 * Default constructor.
	 */
	public IconCellRenderer() {
		editable = true;
		clickable = true;

		noFocusBorder = new EmptyBorder(1, 1, 1, 1);
		treeFocusBorder = new LineBorder(UIManager.getColor("Tree.selectionBorderColor"));
		setActionCommand(CLICKED);

		rendererPanel = new JPanel();
		rendererPanel.setLayout(new GridBagLayout());

		editorPanel = this;
		editorPanel.setLayout(new GridBagLayout());

		// set up constraints
		GridBagConstraints imageConstraints = new GridBagConstraints();
		imageConstraints.gridx = 0;
		GridBagConstraints labelConstraints = new GridBagConstraints();
		labelConstraints.fill = GridBagConstraints.HORIZONTAL;
		labelConstraints.gridx = 1;
		labelConstraints.weightx = 1.0;
		labelConstraints.ipadx = 1;
		labelConstraints.insets = new Insets(0, 1, 0, 0); // sweat the pixel

		// make the editor panel go away when not in use
		// and pass through all mouse events to container

		// this is not very useful since editorLabel and editorButton
		// get all of the events
		editorPanel.addMouseListener(this);

		rendererLabel = new JLabel();
		rendererLabel.setOpaque(false);
		rendererPanel.add(rendererLabel, labelConstraints);

		editorLabel = new JLabel();
		editorLabel.setText(""); // default state
		editorLabel.setOpaque(false);
		editorPanel.add(editorLabel, labelConstraints);

		unselectedForeground = rendererLabel.getForeground();
		unselectedBackground = rendererLabel.getBackground();

		rendererButton = new JButton();
		rendererButton.setBorder(null);
		rendererButton.setBorderPainted(false);
		rendererButton.setContentAreaFilled(false);
		rendererButton.setFocusPainted(false);
		rendererButton.setMargin(new Insets(0, 0, 0, 0));
		rendererPanel.add(rendererButton, imageConstraints);

		editorButton = new JButton();
		editorButton.setEnabled(clickable); // default state
		editorButton.setIcon(null); // default state
		editorButton.setBorder(null);
		editorButton.setBorderPainted(false);
		editorButton.setContentAreaFilled(false);
		editorButton.setFocusPainted(false);
		editorButton.setMargin(new Insets(0, 0, 0, 0));
		editorPanel.add(editorButton, imageConstraints);

		editorButton.addActionListener(this);

		// add these in order to dispatch the MouseEvents
		// to the lastKnownComponent, and proper management of
		// DnD operations
		editorLabel.addMouseListener(this);
		editorButton.addMouseListener(this);
	}

	/**
	 * Returns the text string currently displayed in the editor component.
	 */
	public String getText() {
		return editorLabel.getText();
	}

	/**
	 * Sets the text string displayed in the editor component. Default is an empty
	 * string.
	 */
	public void setText(String aString) {
		editorLabel.setText(aString);
	}

	/**
	 * Returns the icon currently displayed in the editor component.
	 */
	public Icon getIcon() {
		return editorButton.getIcon();
	}

	/**
	 * Sets the icon currently displayed in the editor component. Default is null.
	 */
	public void setIcon(Icon anIcon) {
		editorButton.setIcon(anIcon);
		if (!isClickable()) {
			editorButton.setDisabledIcon(anIcon);
		}
	}

	/**
	 * Returns whether the editor component's label text is editable.
	 */
	public boolean isEditable() {
		return editable;
	}

	/**
	 * Sets whether the editor component's label text is editable. Default is true.
	 * Editable text is not yet implemented.
	 */
	public void setEditable(boolean isEditable) {
		editable = isEditable;
	}

	/**
	 * Returns whether the editor component's icon is clickable.
	 */
	public boolean isClickable() {
		return clickable;
	}

	/**
	 * Sets whether the editor component's icon is clickable. Default is true.
	 */
	public void setClickable(boolean isClickable) {
		clickable = isClickable;
		editorButton.setEnabled(clickable);
	}

	/**
	 * Returns the component from getRendererForContext.
	 */
	public Component getListCellRendererComponent(JList list, Object value, int index, boolean isSelected,
			boolean cellHasFocus) {
		lastKnownComponent = list;
		return getRendererForContext(list, value, index, 0, isSelected, cellHasFocus, false, true);
	}

	/**
	 * Returns the component from getRendererForContext.
	 */
	public Component getTableCellRendererComponent(JTable table, Object value, boolean isSelected, boolean hasFocus,
			int row, int column) {
		lastKnownComponent = table;
		return getRendererForContext(table, value, row, column, isSelected, hasFocus, false, true);
	}

	/**
	 * Returns the component from getRendererForContext.
	 */
	public Component getTreeCellRendererComponent(JTree tree, Object value, boolean selected, boolean expanded,
			boolean leaf, int row, boolean hasFocus) {
		lastKnownComponent = tree;
		return getRendererForContext(tree, value, row, 0, selected, hasFocus, expanded, leaf);
	}

	/**
	 * Returns getEditorForContext with the same parameters with hasFocus true.
	 */
	public Component getTableCellEditorComponent(JTable table, Object value, boolean isSelected, int row, int column) {
		lastKnownValue = value;
		lastKnownComponent = table;
		return getEditorForContext(table, value, row, column, isSelected, true, false, true);
	}

	/**
	 * Returns the component from getEditorForContext with hasFocus true.
	 */
	public Component getTreeCellEditorComponent(JTree tree, Object value, boolean isSelected, boolean expanded,
			boolean leaf, int row) {

		lastKnownValue = value;
		lastKnownComponent = tree;

		return getEditorForContext(tree, value, row, 0, isSelected, true, expanded, leaf);
	}

	/**
	 * This default implementation returns a JPanel that is configured by calling
	 * configureComponentForContext.
	 * 
	 * @return An component that is used to render content.
	 */
	public Component getRendererForContext(JComponent container, Object value, int row, int column, boolean isSelected,
			boolean hasFocus, boolean isExpanded, boolean isLeaf) {

		configureComponentForContext(rendererPanel, rendererButton, rendererLabel, container, value, row, column,
				isSelected, hasFocus, isExpanded, isLeaf);
		return rendererPanel;
	}

	/**
	 * This method returns a separate component that should be visually identical to
	 * the renderer component. We can't simply reuse the renderer component because
	 * the renderer is still used to paint the table while the editor component is
	 * displayed. Clicks are received on this component. This default implementation
	 * returns a JPanel that is configured by calling configureComponentForContext.
	 * 
	 * @return A component used to receive clicks on the cell.
	 */
	public Component getEditorForContext(JComponent container, Object value, int row, int column, boolean isSelected,
			boolean hasFocus, boolean isExpanded, boolean isLeaf) {
		configureComponentForContext(editorPanel, editorButton, editorLabel, container, value, row, column, true,
				hasFocus, isExpanded, isLeaf); // editor should always be selected

		return editorPanel;
	}

	/**
	 * Called to configure components
	 */
	protected void configureComponentForContext(JPanel component, JButton iconButton, JLabel label,
			JComponent container, Object value, int row, int column, boolean isSelected, boolean hasFocus,
			boolean isExpanded, boolean isLeaf) {
		if (hasFocus) {
			if (container instanceof JTable) {
				component.setBorder(UIManager.getBorder("Table.focusCellHighlightBorder"));
			} else {
				component.setBorder(noFocusBorder);
			}

			if (container instanceof JTree) // was: (false)
			{
				label.setBorder(treeFocusBorder);
			} else {
				label.setBorder(noFocusBorder);
			}
		} else {
			label.setBorder(noFocusBorder);
			component.setBorder(noFocusBorder);
		}

		if (isSelected) {
			if (container instanceof JTree) {
				label.setOpaque(true);
				label.setForeground(UIManager.getColor("Tree.selectionForeground"));
				label.setBackground(UIManager.getColor("Tree.selectionBackground"));
				component.setBackground(container.getBackground());
			} else if (container instanceof JTable) {
				label.setOpaque(false);
				label.setForeground(((JTable) container).getSelectionForeground());
				component.setBackground(((JTable) container).getSelectionBackground());
			} else {
				label.setOpaque(false);
				label.setForeground(UIManager.getColor("Table.selectionForeground"));
				component.setBackground(UIManager.getColor("Table.selectionBackground"));
			}
		} else {
			label.setOpaque(false);
			label.setForeground(container.getForeground());
			component.setBackground(container.getBackground());
		}

		label.setFont(container.getFont());

		Icon icon = getIconForContext(container, value, row, column, isSelected, hasFocus, isExpanded, isLeaf);
		iconButton.setIcon(icon);
		if (!isClickable()) {
			iconButton.setDisabledIcon(icon);
		}

		String text = getStringForContext(container, value, row, column, isSelected, hasFocus, isExpanded, isLeaf);

		if ((text == null) || ("".equals(text))) {
			if (!label.getText().equals(""))
				label.setText("");
		} else {
			if (!label.getText().equals(text))
				label.setText(text);
		}
	}

	/**
	 * Override this method to provide an icon for the renderer. This default
	 * implementation returns null.
	 * 
	 * @return An icon to be displayed in the cell, or null to omit the icon from
	 *         the cell.
	 */
	public Icon getIconForContext(JComponent container, Object value, int row, int column, boolean isSelected,
			boolean hasFocus, boolean isExpanded, boolean isLeaf) {
		return null;
	}

	/**
	 * Override this method to provide a string for the renderer. This default
	 * implementation returns toString on the value parameter, or null if the value
	 * is null.
	 * 
	 * @return A string to be displayed in the cell.
	 */
	public String getStringForContext(JComponent container, Object value, int row, int column, boolean isSelected,
			boolean hasFocus, boolean isExpanded, boolean isLeaf) {
		if (value == null)
			return null;
		return value.toString();
	}

	/**
	 * Adds the specified listener to the list of listeners to be notified when the
	 * button receives a click.
	 */
	public void addActionListener(ActionListener aListener) {
		if (actionListeners == null) {
			actionListeners = new Vector(2);
		}
		actionListeners.add(aListener);
	}

	/**
	 * Removes the specified listener from the list of listeners to be notified when
	 * the button receives a click.
	 */
	public void removeActionListener(ActionListener aListener) {
		actionListeners.remove(aListener);
	}

	/**
	 * Broadcasts the specified action event to all listeners.
	 */
	protected void fireActionEvent(ActionEvent anActionEvent) {
		if (actionListeners == null)
			return;
		// vector's enumeration is not fail-fast
		Enumeration e = actionListeners.elements();
		while (e.hasMoreElements()) {
			((ActionListener) e.nextElement()).actionPerformed(anActionEvent);
		}
	}

	/**
	 * Returns the action command broadcast when this icon receives a click.
	 * Defaults to CLICKED.
	 */
	public String getActionCommand() {
		return actionCommand;
	}

	/**
	 * Sets the action command broadcast when this table receives a double click.
	 */
	public void setActionCommand(String anActionCommand) {
		actionCommand = anActionCommand;
	}

// interface CellEditor

	/**
	 * Returns lastKnownValue, although this should not be called.
	 */
	public Object getCellEditorValue() {
		return lastKnownValue;
	}

	/**
	 * Returns true.
	 */
	public boolean isCellEditable(EventObject anEvent) {
		return true;
	}

	/**
	 * Returns true.
	 */
	public boolean shouldSelectCell(EventObject anEvent) {
		return true;
	}

	/**
	 * Fires an editing stopped event and returns true.
	 */
	public boolean stopCellEditing() {
		ChangeEvent event = new ChangeEvent(this);
		if (cellEditorListeners != null) {
			// vector's enumeration is not fail-fast
			Enumeration e = cellEditorListeners.elements();
			while (e.hasMoreElements()) {
				// broadcast editing cancelled since no value is edited
				((CellEditorListener) e.nextElement()).editingCanceled(event);
			}
		}
		lastKnownComponent = null;
		return true;
	}

	/**
	 * Fires an editing cancelled event and returns true.
	 */
	public void cancelCellEditing() {
		// HACK: cancelCellEditing() causes for the dragGesture
		// to be NOT recognized AT ALL since on the next MOUSE_PRESSED
		// the cell editor first needs to startEditing() [if in the tree
		// the CellEditorListener is a BasicTreeUI class]
		// (before the drag gesture event can be recognized).
		// Also the lastKnownComponent should not be set to null,
		// none of the mouse events won't dispathced to the lastKnownComponent
		// in that case.

		// Not calling it at all does seem to fix it, but what are the
		// consequences???
		// Trying to workaround this might solve it, but it introduces having
		// an extra listener (a MouseMotionListnener), which might be wasteful
		// (i.e. only if a Mouse_dragged event has been initiated, but DragGesture
		// hasn't been recognized, postpone calling this till finish the DnD event)
		// But what if do DnD and not exited ??? The mouseExited() is not called
		// anyway until the DnD event is done.

		ChangeEvent event = new ChangeEvent(this);
		if (cellEditorListeners == null)
			return;
		// vector's enumeration is not fail-fast
		Enumeration e = cellEditorListeners.elements();

		while (e.hasMoreElements()) {
			((CellEditorListener) e.nextElement()).editingCanceled(event);
		}

		// DO not nullify this
		lastKnownComponent = null;
	}

	/**
	 * Adds the specified listener to the list of listeners to be notified when the
	 * table receives a double click.
	 */
	public void addCellEditorListener(CellEditorListener aListener) {
		if (cellEditorListeners == null) {
			cellEditorListeners = new Vector(2);
		}
		cellEditorListeners.add(aListener);
	}

	/**
	 * Removes the specified listener from the list of listeners to be notified when
	 * the table receives a double click.
	 */
	public void removeCellEditorListener(CellEditorListener aListener) {
		cellEditorListeners.remove(aListener);
	}

// interface ActionListener

	/**
	 * Puts ourself on the end of the event queue for firing our action event to all
	 * listeners.
	 */
	public void actionPerformed(ActionEvent evt) {
		// commented out in order NOT to set lastKnownComponent to null, since
		// if this object is inside a table or tree, relying on getCellEditorValue()
		// to return the currently edited object
		// cancelCellEditing();

		SwingUtilities.invokeLater(this);
	}

// interface Runnable

	/**
	 * Fires the action event to all listeners. This is triggered by a click on the
	 * icon.
	 */
	public void run() {
		fireActionEvent(new ActionEvent(this, 0, getActionCommand()));
	}

// interface MouseListener 

	/**
	 * Passes through editor mouse clicks to last known component. (left click only)
	 */
	public void mouseClicked(MouseEvent e) {
		if (lastKnownComponent != null) {
			Object source = e.getSource();
			if (source != null) {
				if (source == editorPanel) {
					lastKnownComponent
							.dispatchEvent(SwingUtilities.convertMouseEvent(editorPanel, e, lastKnownComponent));

				} else if (source == editorLabel) {
					lastKnownComponent
							.dispatchEvent(SwingUtilities.convertMouseEvent(editorLabel, e, lastKnownComponent));
				}

				else if (source == editorButton) {
					lastKnownComponent
							.dispatchEvent(SwingUtilities.convertMouseEvent(editorButton, e, lastKnownComponent));
				}
			}
		}
	}

	/**
	 * Passes through editor right-mouse (popup trigger) mouse events to last known
	 * component. Needed for possible displaying of popup menus on right click
	 */
	public void mousePressed(MouseEvent e) {
		if (e.isPopupTrigger()) {
			if (lastKnownComponent != null) {
				Object source = e.getSource();
				if (source != null) {
					if (source == editorPanel) {
						lastKnownComponent
								.dispatchEvent(SwingUtilities.convertMouseEvent(editorPanel, e, lastKnownComponent));
					} else if (source == editorLabel) {
						lastKnownComponent
								.dispatchEvent(SwingUtilities.convertMouseEvent(editorLabel, e, lastKnownComponent));
					}

					else if (source == editorButton) {
						lastKnownComponent
								.dispatchEvent(SwingUtilities.convertMouseEvent(editorButton, e, lastKnownComponent));
					}
				}
			}
		}
	}

	/**
	 * Does nothing.
	 */
	public void mouseReleased(MouseEvent e) {
		if (e.isPopupTrigger()) {
			if (lastKnownComponent != null) {

				Object source = e.getSource();
				if (source != null) {
					if (source == editorPanel) {
						lastKnownComponent
								.dispatchEvent(SwingUtilities.convertMouseEvent(editorPanel, e, lastKnownComponent));
					}

					else if (source == editorLabel) {
						lastKnownComponent
								.dispatchEvent(SwingUtilities.convertMouseEvent(editorLabel, e, lastKnownComponent));
					}

					else if (source == editorButton) {
						lastKnownComponent
								.dispatchEvent(SwingUtilities.convertMouseEvent(editorButton, e, lastKnownComponent));
					}
				}
			}
		}
	}

	/**
	 * Does nothing.
	 */
	public void mouseEntered(MouseEvent e) {
	}

	/**
	 * Cancels cell editing.
	 */
	public void mouseExited(MouseEvent e) {
		Object source = e.getSource();
		if (source != null && source instanceof JComponent) {
			// need to convert the Point from the source's coordinate system to
			// editorPanel's coordinate system.
			// (note that simple editorPanel.contains(e.getPoint()) fails if source is
			// editorButton)

			Point convertedPoint = SwingUtilities.convertPoint((JComponent) source, e.getPoint(), editorPanel);

			// check if exited from editorButton, but still inside the editorPanel (works
			// for editorLabel as well)
			if (!editorPanel.contains(convertedPoint)) {

				// This was getting called before, but it interfers with the DnD operation
				cancelCellEditing();
			}
		}
	}

	/*
	 * This might be redundant public void cleanUp(){
	 * 
	 * //since cancelCellEditing() was never called call it now cancelCellEditing();
	 * stopCellEditing();
	 * 
	 * editorButton.removeActionListener( this ); editorPanel.removeMouseListener(
	 * this ); editorLabel.removeMouseListener( this );
	 * editorButton.removeMouseListener( this ); lastKnownComponent = null;
	 * lastKnownValue = null; }
	 */
}