Slider
s
and ProgressBar
s.
Defines four interrelated integer properties: minimum, maximum, extent
and value. These four integers define two nested ranges like this:
minimum <= value <= value+extent <= maximumThe outer range is
minimum,maximum
and the inner
range is value,value+extent
. The inner range
must lie within the outer one, i.e. value
must be
less than or equal to maximum
and value+extent
must greater than or equal to minimum
, and maximum
must be greater than or equal to minimum
.
There are a few features of this model that one might find a little
surprising. These quirks exist for the convenience of the
Swing BoundedRangeModel clients, such as Slider
and
ScrollBar
.
value == maximum
, setExtent(10)
would change the extent (back) to zero.
For an example of specifying custom bounded range models used by sliders, see The Anatomy of a Swing-Based Program in The Java Tutorial.
maximum - extent
and the lower limit is minimum
.When a BoundedRange model is used with a scrollbar the extent defines the length of the scrollbar knob (aka the "thumb" or "elevator"). The extent usually represents how much of the object being scrolled is visible. When used with a slider, the extent determines how much the value can "jump", for example when the user presses PgUp or PgDn.
Notifies any listeners if the model changes.
minimum <= value <= value+extent <= maximum
Notifies any listeners if the model changes.
minimum <= value <= value+extent <= maximum
Notifies any listeners if the model changes.
newValue
if newValue
satisfies the model's constraints. Those constraints are:
minimum <= value <= value+extent <= maximumOtherwise, if
newValue
is less than minimum
it's set to minimum
, if its greater than
maximum
then it's set to maximum
, and
if it's greater than value+extent
then it's set to
value+extent
.
When a BoundedRange model is used with a scrollbar the value specifies the origin of the scrollbar knob (aka the "thumb" or "elevator"). The value usually represents the origin of the visible part of the object being scrolled.
Notifies any listeners if the model changes.
Sliders and scrollbars use this property when a drag is underway.