Symantec Visual Cafe for Java 2.5/symantec-visual-cafe-2.5-database-dev-edition.iso/Visual Cafe Pro v1.0/SOURCE.BIN/NervousText.java

Java Source | 1997-06-19 | 5.3 KB | 210 lines

package symantec.itools.multimedia;


import java.awt.Canvas;
import java.awt.Dimension;

//     01/29/97    TWB    Integrated changes from Macintosh

/**
 * NervousText control.
 * Creates animated text in which each letter moves independently of all other letters.
 *
 * @version 1.0, Nov 26, 1996
 * @author Symantec
 */

public class NervousText
    extends Canvas
    implements Runnable
{
    char separated[];
    String text;
    boolean paused;
    Thread jitter = null;


    /**
     * Create defalut NervousText object. Default object contains the word "text".
     */

    public NervousText()
    {
        paused = false;
        setText("text");
    }

    /**
     * Tells this component that it has been added to a container.
     * This is a standard Java AWT method which gets called by the AWT when
     * this component is added to a container. Typically, it is used to
     * create this component's peer.
     *
     * It has been overridden here to start the nervous text thread.
     *
     * @see #removeNotify
     */

    public void addNotify()
    {
        super.addNotify();
        jitter = new Thread(this);
        jitter.start();
    }

    /**
     * Tells this component that it is being removed from a container.
     * This is a standard Java AWT method which gets called by the AWT when
     * this component is removed from a container. Typically, it is used to
     * destroy the peers of this component and all its subcomponents.
     *
     * It has been overridden here to stop the nervous text thread.
     *
     * @see #addNotify
     */
    public synchronized void removeNotify() {
        if (jitter != null){
            jitter.stop();
            jitter = null;
        }
        super.removeNotify();
    }

    /**
     * Makes this component visible.
     * This is a standard Java AWT method which gets called to show this
     * component. If this component was invisible due to a previous hide()
     * call it make this component visible again.
     *
     * @see #hide
     */
    public synchronized void show() {
        super.show();
        if (isVisible()) {
            if (jitter != null)
                jitter.resume();
        }
    }

    /**
     * Makes this component invisible.
     * This is a standard Java AWT method which gets called to hide
     * this component. A hidden component cannot be seen by the user nor
     * does it take up space in its container, but it does continue to
     * exist.
     *
     * @see #show
     */
    public synchronized void hide() {
        super.hide();
        if (!isVisible()) {
            if (jitter != null)
                jitter.suspend();
        }
    }

    /**
     * Specify the text that will be displayed by NervousText.
     *
     * @param str text to be shown as nervous text
     */

    public void setText(String str)
    {
        text = str;
        separated =  new char[text.length()];
        text.getChars(0, text.length(), separated, 0);
    }

    /**
     * Obtain the text that is currently being displayed.
     *
     * @return text that is being shown by this component
     */
    public String getText()
    {
        return text;
    }

    /**
     * NervousText thread body.  This method is called by the Java virtual
     * machine to when this thread starts.
     */
    public void run()
    {
        while (true)
        {

            try
            {
                Thread.sleep(150);
            }
            catch(Exception e)
            {
            }
            if (!paused)
            {
                repaint();
            }
        }
    }

    /**
     * Temporarily suspend the animation of the nervous text.
     * @param f pause the animation of true
     *
     */
    public void pause(boolean f)
    {
        paused = f;
    }

    /**
     * Obtain animator's current state.
     *
     * @return true if the animator is paused, false if it is running
     */

    public boolean isPaused()
    {
        return paused;
    }
    /**
     * Temporarily suspend the animation of the nervous text. Identical
     * to pause(boolean).
     * @param f pause the animation of true
     *
     */
    public void setPaused(boolean f)
    {
        paused = f;
    }

    /**
     * Paints this component using the given graphics context.
     * This is a standard Java AWT method which typically gets called
     * by the AWT to handle painting this component. It paints this component
     * using the given graphics context. The graphics context clipping region
     * is set to the bounding rectangle of this component and its <0,0>
     * coordinate is this component's top-left corner.
     *
     * @param g the graphics context used for painting
     * @see java.awt.Component#repaint
     * @see java.awt.Component#update
     */
    public void paint(java.awt.Graphics g)
    {
        Dimension dim = size();
        g.clipRect(0,0,dim.width,dim.height);

        for(int i = 0;i < text.length(); i++)
        {
            int x_coord;
            int y_coord;
            x_coord = (int) (Math.random() * 10 + 20 * i);
            y_coord = (int) (Math.random() * 10 + 36);
            g.drawChars(separated, i, 1, x_coord, y_coord);
        }
    }
}