The Adjustable Interface

The Adjustable interface is new to Java 1.1. It provides the method signatures required for an object that lets you adjust a bounded integer value. It is currently implemented by Scrollbar and returned by two methods within ScrollPane.

Constants of the Adjustable Interface

There are two direction specifiers for Adjustable.

• public final static int HORIZONTAL
• HORIZONTAL is the constant for horizontal orientation.
• public final static int VERTICAL
• VERTICAL is the constant for vertical orientation.

Methods of the Adjustable Interface

• public abstract int getOrientation ()
• The getOrientation() method is for returning the current orientation of the adjustable object, either Adjustable.HORIZONTAL or Adjustable.VERTICAL.

  setOrientation() is not part of the interface. Not all adjustable objects need to be able to alter orientation. For example, Scrollbar instances can change their orientation, but each Adjustable instance associated with a ScrollPane has a fixed, unchangeable orientation.

• public abstract int getVisibleAmount ()
• The getVisibleAmount() method lets you retrieve the size of the visible slider of the adjustable object.
• public abstract void setVisibleAmount (int amount)
• The setVisibleAmount() method lets you change the size of the visible slider to amount.
• public abstract int getValue ()
• The getValue() method lets you retrieve the current value of the adjustable object.
• public abstract void setValue (int value)
• The setValue() method lets you change the value of the adjustable object to value.
• public abstract int getMinimum ()
• The getMinimum() method lets you retrieve the current minimum setting for the object.
• public abstract void setMinimum (int minimum)
• The setMinimum() method lets you change the minimum value of the adjustable object to minimum.
• public abstract int getMaximum ()
• The getMaximum() method lets you retrieve the current maximum setting for the object.
• public abstract void setMaximum (int maximum)
• The setMaximum() method lets you change the maximum value of the adjustable object to maximum.
• public abstract int getUnitIncrement ()
• The getUnitIncrement() method lets you retrieve the current line increment.
• public abstract void setUnitIncrement (int amount)
• The setUnitIncrement() method lets you change the line increment amount of the adjustable object to amount.
• public abstract int getBlockIncrement ()
• The getBlockIncrement() method lets you retrieve the current page increment.
• public abstract void setBlockIncrement (int amount)
• The setBlockIncrement() method lets you change the paging increment amount of the adjustable object to amount.
• public abstract void addAdjustmentListener(AdjustmentListener listener)
• The addAdjustmentListener() method lets you register listener as an object interested in being notified when an AdjustmentEvent passes through the EventQueue with this Adjustable object as its target.
• public abstract void removeAdjustmentListener(ItemListener listener)
• The removeAdjustmentListener() method removes listener as a interested listener. If listener is not registered, nothing happens.