gcc/libjava/javax/swing/ToolTipManager.java

/* ToolTipManager.java --
   Copyright (C) 2002, 2004 Free Software Foundation, Inc.

This file is part of GNU Classpath.

GNU Classpath is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
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GNU Classpath is distributed in the hope that it will be useful, but
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
General Public License for more details.

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Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA.

Linking this library statically or dynamically with other modules is
making a combined work based on this library.  Thus, the terms and
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As a special exception, the copyright holders of this library give you
permission to link this library with independent modules to produce an
executable, regardless of the license terms of these independent
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package javax.swing;

import java.awt.AWTEvent;
import java.awt.Component;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.Insets;
import java.awt.LayoutManager;
import java.awt.Panel;
import java.awt.Point;
import java.awt.Rectangle;
import java.awt.event.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.event.MouseMotionListener;
import javax.swing.JComponent;
import javax.swing.Popup;
import javax.swing.PopupFactory;
import javax.swing.SwingUtilities;
import javax.swing.Timer;


/**
 * This class is responsible for the registration of JToolTips to Components
 * and for displaying them when appropriate.
 */
public class ToolTipManager extends MouseAdapter implements MouseMotionListener
{
  /**
   * This ActionListener is associated with the Timer that listens to whether
   * the JToolTip can be hidden after four seconds.
   */
  protected class stillInsideTimerAction implements ActionListener
  {
    /**
     * This method creates a new stillInsideTimerAction object.
     */
    protected stillInsideTimerAction()
    {
    }

    /**
     * This method hides the JToolTip when the Timer has finished.
     *
     * @param event The ActionEvent.
     */
    public void actionPerformed(ActionEvent event)
    {
      hideTip();
    }
  }

  /**
   * This Actionlistener is associated with the Timer that listens to whether
   * the mouse cursor has re-entered the JComponent in time for an immediate
   * redisplay of the JToolTip.
   */
  protected class outsideTimerAction implements ActionListener
  {
    /**
     * This method creates a new outsideTimerAction object.
     */
    protected outsideTimerAction()
    {
    }

    /**
     * This method is called when the Timer that listens to whether the mouse
     * cursor has re-entered the JComponent has run out.
     *
     * @param event The ActionEvent.
     */
    public void actionPerformed(ActionEvent event)
    {
    }
  }

  /**
   * This ActionListener is associated with the Timer that listens to whether
   * it is time for the JToolTip to be displayed after the mouse has entered
   * the JComponent.
   */
  protected class insideTimerAction implements ActionListener
  {
    /**
     * This method creates a new insideTimerAction object.
     */
    protected insideTimerAction()
    {
    }

    /**
     * This method displays the JToolTip when the Mouse has been still for the
     * delay.
     *
     * @param event The ActionEvent.
     */
    public void actionPerformed(ActionEvent event)
    {
      showTip();
      if (insideTimer != null)
	insideTimer.start();
    }
  }

  /**
   * The Timer that determines whether the Mouse has been still long enough
   * for the JToolTip to be displayed.
   */
  Timer enterTimer;

  /**
   * The Timer that determines whether the Mouse has re-entered the JComponent
   * quickly enough for the JToolTip to be displayed immediately.
   */
  Timer exitTimer;

  /**
   * The Timer that determines whether the JToolTip has been displayed long
   * enough for it to be hidden.
   */
  Timer insideTimer;

  /** A global enabled setting for the ToolTipManager. */
  private transient boolean enabled = true;

  /** lightWeightPopupEnabled */
  protected boolean lightWeightPopupEnabled = true;

  /** heavyWeightPopupEnabled */
  protected boolean heavyWeightPopupEnabled = false;

  /** The shared instance of the ToolTipManager. */
  private static ToolTipManager shared;

  /** The current component the tooltip is being displayed for. */
  private static Component currentComponent;

  /** The current tooltip. */
  private static JToolTip currentTip;

  /** The last known position of the mouse cursor. */
  private static Point currentPoint;

  /**
   * The panel that holds the tooltip when the tooltip is displayed fully
   * inside the current container.
   */
  private static Container containerPanel;

  /**
   * The window used when the tooltip doesn't fit inside the current
   * container.
   */
  private static JWindow tooltipWindow;

  /**
   * Creates a new ToolTipManager and sets up the timers.
   */
  ToolTipManager()
  {
    enterTimer = new Timer(750, new insideTimerAction());
    enterTimer.setRepeats(false);

    insideTimer = new Timer(4000, new stillInsideTimerAction());
    insideTimer.setRepeats(false);

    exitTimer = new Timer(500, new outsideTimerAction());
    exitTimer.setRepeats(false);
  }

  /**
   * This method returns the shared instance of ToolTipManager used by all
   * JComponents.
   *
   * @return The shared instance of ToolTipManager.
   */
  public static ToolTipManager sharedInstance()
  {
    if (shared == null)
      shared = new ToolTipManager();

    return shared;
  }

  /**
   * This method sets whether ToolTips are enabled or disabled for all
   * JComponents.
   *
   * @param enabled Whether ToolTips are enabled or disabled for all
   *        JComponents.
   */
  public void setEnabled(boolean enabled)
  {
    if (! enabled)
      {
	enterTimer.stop();
	exitTimer.stop();
	insideTimer.stop();
      }

    this.enabled = enabled;
  }

  /**
   * This method returns whether ToolTips are enabled.
   *
   * @return Whether ToolTips are enabled.
   */
  public boolean isEnabled()
  {
    return enabled;
  }

  /**
   * This method returns whether LightweightToolTips are enabled.
   *
   * @return Whether LighweightToolTips are enabled.
   */
  public boolean isLightWeightPopupEnabled()
  {
    return lightWeightPopupEnabled;
  }

  /**
   * This method sets whether LightweightToolTips are enabled. If you mix
   * Lightweight and Heavyweight components, you must set this to false to
   * ensure that the ToolTips popup above all other components.
   *
   * @param enabled Whether LightweightToolTips will be enabled.
   */
  public void setLightWeightPopupEnabled(boolean enabled)
  {
    lightWeightPopupEnabled = enabled;
    heavyWeightPopupEnabled = ! enabled;
  }

  /**
   * This method returns the initial delay before the ToolTip is shown when
   * the mouse enters a Component.
   *
   * @return The initial delay before the ToolTip is shown.
   */
  public int getInitialDelay()
  {
    return enterTimer.getDelay();
  }

  /**
   * This method sets the initial delay before the ToolTip is shown when the
   * mouse enters a Component.
   *
   * @param delay The initial delay before the ToolTip is shown.
   */
  public void setInitialDelay(int delay)
  {
    enterTimer.setDelay(delay);
  }

  /**
   * This method returns the time the ToolTip will be shown before being
   * hidden.
   *
   * @return The time the ToolTip will be shown before being hidden.
   */
  public int getDismissDelay()
  {
    return insideTimer.getDelay();
  }

  /**
   * This method sets the time the ToolTip will be shown before being hidden.
   *
   * @param delay The time the ToolTip will be shown before being hidden.
   */
  public void setDismissDelay(int delay)
  {
    insideTimer.setDelay(delay);
  }

  /**
   * This method returns the amount of delay where if the mouse re-enters a
   * Component, the tooltip will be shown immediately.
   *
   * @return The reshow delay.
   */
  public int getReshowDelay()
  {
    return exitTimer.getDelay();
  }

  /**
   * This method sets the amount of delay where if the mouse re-enters a
   * Component, the tooltip will be shown immediately.
   *
   * @param delay The reshow delay.
   */
  public void setReshowDelay(int delay)
  {
    exitTimer.setDelay(delay);
  }

  /**
   * This method registers a JComponent with the ToolTipManager.
   *
   * @param component The JComponent to register with the ToolTipManager.
   */
  public void registerComponent(JComponent component)
  {
    component.addMouseListener(this);
    component.addMouseMotionListener(this);
  }

  /**
   * This method unregisters a JComponent with the ToolTipManager.
   *
   * @param component The JComponent to unregister with the ToolTipManager.
   */
  public void unregisterComponent(JComponent component)
  {
    component.removeMouseMotionListener(this);
    component.removeMouseListener(this);
  }

  /**
   * This method is called whenever the mouse enters a JComponent registered
   * with the ToolTipManager. When the mouse enters within the period of time
   * specified by the reshow delay, the tooltip will be displayed
   * immediately. Otherwise, it must wait for the initial delay before
   * displaying the tooltip.
   *
   * @param event The MouseEvent.
   */
  public void mouseEntered(MouseEvent event)
  {
    if (currentComponent != null
        && getContentPaneDeepestComponent(event) == currentComponent)
      return;
    currentPoint = event.getPoint();
    currentComponent = (Component) event.getSource();

    if (exitTimer.isRunning())
      {
	exitTimer.stop();
	showTip();
	insideTimer.start();
	return;
      }

    // This should always be stopped unless we have just fake-exited.
    if (! enterTimer.isRunning())
      enterTimer.start();
  }

  /**
   * This method is called when the mouse exits a JComponent registered with
   * the ToolTipManager. When the mouse exits, the tooltip should be hidden
   * immediately.
   *
   * @param event The MouseEvent.
   */
  public void mouseExited(MouseEvent event)
  {
    if (getContentPaneDeepestComponent(event) == currentComponent)
      return;

    currentPoint = event.getPoint();
    currentComponent = null;
    hideTip();

    if (! enterTimer.isRunning() && insideTimer.isRunning())
      exitTimer.start();
    if (enterTimer.isRunning())
      enterTimer.stop();
    if (insideTimer.isRunning())
      insideTimer.stop();
  }

  /**
   * This method is called when the mouse is pressed on a JComponent
   * registered with the ToolTipManager. When the mouse is pressed, the
   * tooltip (if it is shown) must be hidden immediately.
   *
   * @param event The MouseEvent.
   */
  public void mousePressed(MouseEvent event)
  {
    currentPoint = event.getPoint();
    if (enterTimer.isRunning())
      enterTimer.restart();
    else if (insideTimer.isRunning())
      {
	insideTimer.stop();
	hideTip();
      }
    currentComponent.invalidate();
    currentComponent.validate();
    currentComponent.repaint();
  }

  /**
   * This method is called when the mouse is dragged in a JComponent
   * registered with the ToolTipManager.
   *
   * @param event The MouseEvent.
   */
  public void mouseDragged(MouseEvent event)
  {
    currentPoint = event.getPoint();
    if (enterTimer.isRunning())
      enterTimer.restart();
  }

  /**
   * This method is called when the mouse is moved in a JComponent registered
   * with the ToolTipManager.
   *
   * @param event The MouseEvent.
   */
  public void mouseMoved(MouseEvent event)
  {
    currentPoint = event.getPoint();
    if (currentTip != null)
      currentTip.setTipText(((JComponent) currentComponent).getToolTipText(event));
    if (enterTimer.isRunning())
      enterTimer.restart();
  }

  /**
   * This method displays the ToolTip. It can figure out the method needed to
   * show it as well (whether to display it in heavyweight/lightweight panel
   * or a window.)
   */
  private void showTip()
  {
    if (! enabled)
      return;

    if (currentTip == null
        || currentTip.getComponent() != currentComponent
        && currentComponent instanceof JComponent)
      currentTip = ((JComponent) currentComponent).createToolTip();
    Point p = currentPoint;
    Dimension dims = currentTip.getPreferredSize();
    if (canToolTipFit(currentTip))
      {
	JLayeredPane pane = ((JRootPane) SwingUtilities.getAncestorOfClass(JRootPane.class,
	                                                                   currentComponent))
	                    .getLayeredPane();

	// This should never happen, but just in case.
	if (pane == null)
	  return;

	if (containerPanel != null)
	  hideTip();
	if (isLightWeightPopupEnabled())
	  {
	    containerPanel = new Panel();
	    JRootPane root = new JRootPane();
	    root.getContentPane().add(currentTip);
	    containerPanel.add(root);
	  }
	else
	  {
	    containerPanel = new JPanel();
	    containerPanel.add(currentTip);
	  }
	LayoutManager lm = containerPanel.getLayout();
	if (lm instanceof FlowLayout)
	  {
	    FlowLayout fm = (FlowLayout) lm;
	    fm.setVgap(0);
	    fm.setHgap(0);
	  }

	p = getGoodPoint(p, pane, currentTip, dims);

	pane.add(containerPanel);
	containerPanel.setBounds(p.x, p.y, dims.width, dims.height);
	currentTip.setBounds(0, 0, dims.width, dims.height);

	pane.revalidate();
	pane.repaint();
      }
    else
      {
	SwingUtilities.convertPointToScreen(p, currentComponent);
	tooltipWindow = new JWindow();
	tooltipWindow.getContentPane().add(currentTip);
	tooltipWindow.setFocusable(false);
	tooltipWindow.pack();
	tooltipWindow.setBounds(p.x, p.y, dims.width, dims.height);
	tooltipWindow.show();
      }
    currentTip.setVisible(true);
  }

  /**
   * This method hides the ToolTip.
   */
  private void hideTip()
  {
    if (currentTip == null || ! currentTip.isVisible() || ! enabled)
      return;
    currentTip.setVisible(false);
    if (containerPanel != null)
      {
	Container parent = containerPanel.getParent();
	if (parent == null)
	  return;
	parent.remove(containerPanel);
	parent.invalidate();
	parent.validate();
	parent.repaint();

	parent = currentTip.getParent();
	if (parent == null)
	  return;
	parent.remove(currentTip);

	containerPanel = null;
      }
    if (tooltipWindow != null)
      {
	tooltipWindow.hide();
	tooltipWindow.dispose();
	tooltipWindow = null;
      }
  }

  /**
   * This method returns a point in the LayeredPane where the ToolTip can be
   * shown. The point returned (if the ToolTip is to be displayed at the
   * preferred dimensions) will always place the ToolTip inside the
   * currentComponent if possible.
   *
   * @param p The last known good point for the mouse.
   * @param c The JLayeredPane in the first RootPaneContainer up from the
   *        currentComponent.
   * @param tip The ToolTip to display.
   * @param dims The ToolTip preferred dimensions (can be null).
   *
   * @return A good point to place the ToolTip.
   */
  private Point getGoodPoint(Point p, JLayeredPane c, JToolTip tip,
                             Dimension dims)
  {
    if (dims == null)
      dims = tip.getPreferredSize();
    Rectangle bounds = currentComponent.getBounds();
    if (p.x + dims.width > bounds.width)
      p.x = bounds.width - dims.width;
    if (p.y + dims.height > bounds.height)
      p.y = bounds.height - dims.height;

    p = SwingUtilities.convertPoint(currentComponent, p, c);
    return p;
  }

  /**
   * This method returns the deepest component in the content pane for the
   * first RootPaneContainer up from the currentComponent. This method is
   * used in conjunction with one of the mouseXXX methods.
   *
   * @param e The MouseEvent.
   *
   * @return The deepest component in the content pane.
   */
  private Component getContentPaneDeepestComponent(MouseEvent e)
  {
    Component source = (Component) e.getSource();
    Container parent = (Container) SwingUtilities.getAncestorOfClass(JRootPane.class,
                                                                     currentComponent);
    if (parent == null)
      return null;
    parent = ((JRootPane) parent).getContentPane();
    Point p = e.getPoint();
    p = SwingUtilities.convertPoint(source, p, parent);
    Component target = SwingUtilities.getDeepestComponentAt(parent, p.x, p.y);
    return target;
  }

  /**
   * This method returns whether the ToolTip can fit in the first
   * RootPaneContainer up from the currentComponent.
   *
   * @param tip The ToolTip.
   *
   * @return Whether the ToolTip can fit.
   */
  private boolean canToolTipFit(JToolTip tip)
  {
    JRootPane root = (JRootPane) SwingUtilities.getAncestorOfClass(JRootPane.class,
                                                                   currentComponent);
    if (root == null)
      return false;
    Dimension pref = tip.getPreferredSize();
    Dimension rootSize = root.getSize();
    if (rootSize.width > pref.width && rootSize.height > pref.height)
      return true;
    return false;
  }
}