Best books about JAVA programming:

• Head First JAVA, Second Editon
• Effective Java Programming Language Guide
• Professional Java, JDK 5 Edition
• Ivor Horton's Beginning Java 2, JDK 5 Edition

JAVA JSlide Color

The following code adds color to JSlide. User may customize the color showing on JSlide. This example has following Java files:

• MThumbSliderExample.java
• MThumbSlider.java
• MetalMThumbSliderUI.java
• MThumbSliderAdditional.java
• MThumbSliderAdditionalUI.java
• AssistantUIManager.java
  
  
  import java.awt.*;
  import java.awt.event.*;
  import javax.swing.*;
  import javax.swing.event.*;
  import javax.swing.plaf.*;
  import javax.swing.plaf.basic.*;
  

public class MThumbSliderAdditionalUI {

MThumbSlider mSlider;
BasicSliderUI ui;
Rectangle[] thumbRects;
int thumbNum;
private transient boolean isDragging;
Icon thumbRenderer;

Rectangle trackRect;

ChangeHandler changeHandler;
TrackListener trackListener;

public MThumbSliderAdditionalUI(BasicSliderUI ui) {
this.ui = ui;
}

public void installUI(JComponent c) {
mSlider = (MThumbSlider)c;
thumbNum = mSlider.getThumbNum();
thumbRects = new Rectangle[thumbNum];
for (int i=0; i<thumbNum; i++) {
thumbRects[i] = new Rectangle();
}
isDragging = false;
trackListener = new MThumbSliderAdditionalUI.TrackListener(mSlider);
changeHandler = new ChangeHandler();
}

public void uninstallUI(JComponent c) {
thumbRects = null;
trackListener = null;
changeHandler = null;
}


protected void calculateThumbsSize() {
Dimension size = ((MThumbSliderAdditional)ui).getThumbSize();
for (int i=0; i<thumbNum; i++) {
thumbRects[i].setSize( size.width, size.height );
}
}


protected void calculateThumbsLocation() {
for (int i=0; i<thumbNum; i++) {
if ( mSlider.getSnapToTicks() ) {
int tickSpacing = mSlider.getMinorTickSpacing();
if (tickSpacing == 0) {
tickSpacing = mSlider.getMajorTickSpacing();
}
if (tickSpacing != 0) {
int sliderValue = mSlider.getValueAt(i);
int snappedValue = sliderValue;
//int min = mSlider.getMinimumAt(i);
int min = mSlider.getMinimum();
if ( (sliderValue - min) % tickSpacing != 0 ) {
float temp = (float)(sliderValue - min) / (float)tickSpacing;
int whichTick = Math.round( temp );
snappedValue = min + (whichTick * tickSpacing);
mSlider.setValueAt( snappedValue , i);
}
}
}
trackRect = getTrackRect();
if ( mSlider.getOrientation() == JSlider.HORIZONTAL ) {
int value = mSlider.getValueAt(i);
int valuePosition = ((MThumbSliderAdditional)ui).xPositionForValue(value);
thumbRects[i].x = valuePosition - (thumbRects[i].width / 2);
thumbRects[i].y = trackRect.y;

} else {
int valuePosition = ((MThumbSliderAdditional)ui).yPositionForValue(mSlider.getValueAt(i)); // need
thumbRects[i].x = trackRect.x;
thumbRects[i].y = valuePosition - (thumbRects[i].height / 2);
}
}
}


public int getThumbNum() {
return thumbNum;
}

public Rectangle[] getThumbRects() {
return thumbRects;
}

private static Rectangle unionRect = new Rectangle();

public void setThumbLocationAt(int x, int y, int index) {
Rectangle rect = thumbRects[index];
unionRect.setBounds( rect );

rect.setLocation( x, y );
SwingUtilities.computeUnion( rect.x, rect.y, rect.width, rect.height, unionRect );
mSlider.repaint( unionRect.x, unionRect.y, unionRect.width, unionRect.height );
}


public Rectangle getTrackRect() {
return ((MThumbSliderAdditional)ui).getTrackRect();
}




public class ChangeHandler implements ChangeListener {
public void stateChanged(ChangeEvent e) {
if ( !isDragging ) {
calculateThumbsLocation();
mSlider.repaint();
}
}
}



public class TrackListener extends MouseInputAdapter {
protected transient int offset;
protected transient int currentMouseX, currentMouseY;
protected Rectangle adjustingThumbRect = null;
protected int adjustingThumbIndex;
protected MThumbSlider slider;
protected Rectangle trackRect;

TrackListener(MThumbSlider slider) {
this.slider = slider;
}

public void mousePressed(MouseEvent e) {
if ( !slider.isEnabled() ) {
return;
}
currentMouseX = e.getX();
currentMouseY = e.getY();
slider.requestFocus();

for (int i=0; i<thumbNum; i++) {
Rectangle rect = thumbRects[i];
if ( rect.contains(currentMouseX, currentMouseY) ) {

switch ( slider.getOrientation() ) {
case JSlider.VERTICAL:
offset = currentMouseY - rect.y;
break;
case JSlider.HORIZONTAL:
offset = currentMouseX - rect.x;
break;
}
isDragging = true;
slider.setValueIsAdjusting(true);
adjustingThumbRect = rect;
adjustingThumbIndex = i;
return;
}
}
}

public void mouseDragged( MouseEvent e ) {
if ( !slider.isEnabled()
|| !isDragging
|| !slider.getValueIsAdjusting()
|| adjustingThumbRect == null ) {
return;
}
int thumbMiddle = 0;
currentMouseX = e.getX();
currentMouseY = e.getY();

Rectangle rect = thumbRects[adjustingThumbIndex];
trackRect = getTrackRect();
switch ( slider.getOrientation() ) {
case JSlider.VERTICAL:
int halfThumbHeight = rect.height / 2;
int thumbTop = e.getY() - offset;
int trackTop = trackRect.y;
int trackBottom = trackRect.y + (trackRect.height - 1);

thumbTop = Math.max( thumbTop, trackTop - halfThumbHeight );
thumbTop = Math.min( thumbTop, trackBottom - halfThumbHeight );

setThumbLocationAt(rect.x, thumbTop, adjustingThumbIndex);

thumbMiddle = thumbTop + halfThumbHeight;
mSlider.setValueAt( ui.valueForYPosition( thumbMiddle ) , adjustingThumbIndex);
break;

case JSlider.HORIZONTAL:
int halfThumbWidth = rect.width / 2;
int thumbLeft = e.getX() - offset;
int trackLeft = trackRect.x;
int trackRight = trackRect.x + (trackRect.width - 1);

thumbLeft = Math.max( thumbLeft, trackLeft - halfThumbWidth );
thumbLeft = Math.min( thumbLeft, trackRight - halfThumbWidth );

setThumbLocationAt( thumbLeft, rect.y, adjustingThumbIndex);

thumbMiddle = thumbLeft + halfThumbWidth;
mSlider.setValueAt( ui.valueForXPosition( thumbMiddle ), adjustingThumbIndex );
break;
}
}

public void mouseReleased(MouseEvent e) {
if ( !slider.isEnabled() ) {
return;
}
offset = 0;
isDragging = false;
mSlider.setValueIsAdjusting(false);
mSlider.repaint();
}

public boolean shouldScroll(int direction) {
return false;
}

}

}