Code
slider.setUI(new MetalSliderUI() {
protected TrackListener createTrackListener(final JSlider slider) {
return new TrackListener() {
public void mouseDragged(MouseEvent e) {
if(!slider.getSnapToTicks() || slider.getMajorTickSpacing()==0) {
super.mouseDragged(e);
return;
}
//case JSlider.HORIZONTAL:
int halfThumbWidth = thumbRect.width / 2;
int trackLength = trackRect.width;
int trackLeft = trackRect.x-halfThumbWidth;
int trackRight = trackRect.x+(trackRect.width-1)+halfThumbWidth;
int xPos = e.getX();
int snappedPos = xPos;
if (xPos < = trackLeft) {
snappedPos = trackLeft;
} else if (xPos > = trackRight) {
snappedPos = trackRight;
} else {
//int tickSpacing = slider.getMajorTickSpacing();
//float actualPixelsForOneTick = trackLength * tickSpacing
// / (float)slider.getMaximum();
// a problem if you choose to set a negative MINIMUM for
// the JSlider; the calculated drag-positions are wrong.
// Fixed by bobndrew:
int possibleTickPositions=slider.getMaximum()-slider.getMinimum();
int tickSpacing = (slider.getMinorTickSpacing()==0)
? slider.getMajorTickSpacing()
: slider.getMinorTickSpacing();
float actualPixelsForOneTick = trackLength * tickSpacing
/ (float)possibleTickPositions;
xPos -= trackLeft;
snappedPos=(int)(
(Math.round(xPos/actualPixelsForOneTick)*actualPixelsForOneTick)+0.5)
+trackLeft;
offset = 0;
}
MouseEvent me = new MouseEvent(
e.getComponent(), e.getID(), e.getWhen(), e.getModifiers(),
snappedPos, e.getY(),
e.getXOnScreen(), e.getYOnScreen(),
e.getClickCount(), e.isPopupTrigger(), e.getButton());
super.mouseDragged(me);
}
};
}
});
References
