public DoubleProperty thresholdProperty() {
        if (null == threshold) {
            threshold = new DoublePropertyBase(_threshold) {
                @Override protected void invalidated() {
                    final double THRESHOLD = get();
                    if (!isBound() && (THRESHOLD < getMinValue() || THRESHOLD > getMaxValue())) {
                        set(clamp(getMinValue(), getMaxValue(), THRESHOLD));
                    }
                    fireTileEvent(RESIZE_EVENT);
                }
                @Override public Object getBean() { return Tile.this; }
                @Override public String getName() { return "threshold"; }
            };
        }
        return threshold;
    }
Sets the threshold of the tile to the given value. The value
will be clamped to the range of the tile.

@param THRESHOLD
src/main/java/eu/hansolo/tilesfx/Tile.java