Re: Animating auto hide of JPanel inside a JFrame

/* try running this, move mouse to top to expose component, move away to hide it, also can press the button multiple times to expose it. */
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.Timer;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Insets;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseEvent;
import java.awt.event.MouseMotionListener;


/*
 * SlidingLabelTest.java
 *
 * File creation information:
 *
 * Author: Ted Hill
 * Date: Apr 14, 2005
 * Time: 8:59:53 AM
 */

/**
* This class experiments with the 'animation' of showing and hiding a JComponent.
*
* When the mouse is brought close to the top of the panel, a label 'slides' down
* into view. When the mouse moves away from the top of the panel, the label 'rolls up'
* out of view.
* Two Swing Timers are used:
* 1. Slides the label into view.
* 2. Rolls the label up out of view.
*
* There is also a button on the panel. Each time it is clicked, it will move the label
* down slightly. This was added initially before the timers as a way to experiment with
* moving a component.
*
* Note that a null layout is used with absolute positioning.
* Null layout should be fine for the ImageViewer panel where the image is essentially
* painted as the background. That is, when the toolbar slides down, it won't push the
* image down, it will slide over and cover the top of the image.
*/
public class SlidingLabelTest extends JPanel
{
private static final int LABEL_HEIGHT = 30;
private static final int INITIAL_LABEL_WIDTH = 30;

    private static final int TIMER_INTERVAL = 1;
    private static final int PIXEL_DELTA = 2;


    private JLabel label;

private Dimension labelDimension = new Dimension(INITIAL_LABEL_WIDTH, LABEL_HEIGHT);

    private JButton button;

    private int vertOffset = - LABEL_HEIGHT;

    private Timer showTimer = new ShowLabelTimer();
    private Timer hideTimer = new HideLabelTimer();

    public SlidingLabelTest()
    {
        setBackground(Color.BLACK);

        initLabel();
//        positionLabel(vertOffset);

//        setLayout(new BorderLayout());
//        add(label, BorderLayout.NORTH);

        positionLabel(vertOffset);

        setLayout(null);
        add(label);

        addButton();

        addMouseMotionListener(new MouseMotionListener()
        {
            public void mouseDragged(MouseEvent e)
            {
                // TODO: add an implementation
            }

            public void mouseMoved(MouseEvent e)
            {
                final int height = e.getY();

if(height < 10 && ! showTimer.isRunning() && ! label.isVisible())
{
// vertOffset = - LABEL_HEIGHT;
// label.setVisible(true);
showTimer.start();
}
else if (height > LABEL_HEIGHT + 5 && !hideTimer.isRunning() && label.isVisible())
{
hideTimer.start();
}
}
});
}

    private void addButton()
    {
        button = new JButton("Move Label");

        Dimension buttonDimension = new Dimension(100, 30);
        button.setPreferredSize(buttonDimension);
        button.setMaximumSize(buttonDimension);
        button.setMinimumSize(buttonDimension);

        add(button);

        Dimension size = button.getPreferredSize();
        button.setBounds(200, 100, size.width, size.height);

        button.addActionListener(new ActionListener()
        {
            public void actionPerformed(ActionEvent e)
            {
                label.setVisible(true);
                positionLabel(vertOffset);

                vertOffset += 2;
            }
        });
    }

    private void positionLabel(final int offset)
    {
        int panelWidth = getWidth();

        System.out.println("SlidingLabelTest.positionLabel()");
        System.out.println("   offset = " + offset);

        // this will change the label's size
        labelDimension.setSize(panelWidth, LABEL_HEIGHT);


        // insets are zero because no border.
        Insets insets = getInsets();

        Dimension size = label.getPreferredSize();

        label.setBounds(insets.left,
                        offset + insets.top,
                        size.width,
                        size.height);
    }

    private void initLabel()
    {
        label = new JLabel("Test Label");

        label.setMinimumSize(labelDimension);
        label.setPreferredSize(labelDimension);

        label.setBackground(Color.YELLOW);
        label.setOpaque(true);

//        label.setVisible(true);
        label.setVisible(false);

//        label.setLocation(0, 0);
//        label.setBounds(0, 0, 300, 30);
    }

    /**
     * Timer class that is called back at intervals.
     */
    private class ShowLabelTimer extends Timer implements ActionListener
    {
        ShowLabelTimer()
        {
            // first param is callback interval in milliseconds
            super(TIMER_INTERVAL, null);   // call back in millis
            addActionListener(this);
        }

        /**
         * Starts the <code>Timer</code>,
         * causing it to start sending action events
         * to its listeners.
         *
         * @see #stop
         */
        public void start()
        {
            vertOffset = - LABEL_HEIGHT;
            label.setVisible(true);
            super.start();
        }

/**
* update the time display
*/
public void actionPerformed(ActionEvent e)
{
System.out.println("ShowLabelTimer.actionPerformed() vertOffset: " + vertOffset);

            if(vertOffset <= 0)
            {
                positionLabel(vertOffset);
            }
            else
            {
                showTimer.stop();
            }

            vertOffset += PIXEL_DELTA;
        }
    }

    /**
     * Timer class that is called back at intervals.
     */
    private class HideLabelTimer extends Timer implements ActionListener
    {
        HideLabelTimer()
        {
            // first param is callback interval in milliseconds
            super(TIMER_INTERVAL, null);   // call back in millis
            addActionListener(this);
        }

        /**
         * Stops the <code>Timer</code>,
         * causing it to stop sending action events
         * to its listeners.
         *
         * @see #start
         */
        public void stop()
        {
            label.setVisible(false);
            super.stop();    // TODO: add an implementation
        }

/**
* update the time display
*/
public void actionPerformed(ActionEvent e)
{
System.out.println("HideLabelTimer.actionPerformed() vertOffset: " + vertOffset);

            if(vertOffset >= (-LABEL_HEIGHT))
            {
                vertOffset -= PIXEL_DELTA;
                positionLabel(vertOffset);
            }
            else
            {
                hideTimer.stop();
            }
        }
    }



    public static void main(String[ ] args)
    {
        JFrame frame = new JFrame("SlidingLabelTest");

        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

frame.getContentPane( ).add(new SlidingLabelTest( ), BorderLayout.CENTER);
frame.setSize(400, 200);
// frame.pack( );
frame.setVisible(true);
}
}
.