rolloverspinnerlistmodel.java

java swing 开发代码

// RolloverSpinnerListModel.java
// A custom spinner model that rolls over the end of a list back to the
// beginning (or vice versa).
//
package	jswing.ch07;


import javax.swing.*;
import java.util.List;

public class RolloverSpinnerListModel extends SpinnerListModel {

  public RolloverSpinnerListModel(Object[] items) { super(items); }
  public RolloverSpinnerListModel(List items) { super(items); }

  public Object getNextValue() {
    Object nv = super.getNextValue();
    if (nv != null) {
      return nv;
    }
    return getList().get(0);
  }

  public Object getPreviousValue() {
    Object pv = super.getPreviousValue();
    if (pv != null) {
      return pv;
    }
    List l = getList();
    return l.get(l.size() - 1);
  }
}