PC Online 1998 January/PCO0198.ISO/1&1/java.z/java_301/java/awt/List.class

Java Class File | 1996-10-20 | 5.1 KB | 237 lines

package java.awt;

import java.awt.peer.ListPeer;
import java.util.Vector;

public class List extends Component {
   Vector items;
   int rows;
   boolean multipleSelections;
   int[] selected;
   int visibleIndex;

   public List() {
      this(0, false);
   }

   public List(int rows, boolean multipleSelections) {
      this.items = new Vector();
      this.multipleSelections = false;
      this.selected = new int[0];
      this.visibleIndex = -1;
      this.rows = rows;
      this.multipleSelections = multipleSelections;
   }

   public synchronized void addNotify() {
      super.peer = ((Component)this).getToolkit().createList(this);
      super.addNotify();
      this.visibleIndex = -1;
   }

   public synchronized void removeNotify() {
      if (super.peer != null) {
         ListPeer peer = (ListPeer)super.peer;
         this.selected = peer.getSelectedIndexes();
      }

      super.removeNotify();
   }

   public int countItems() {
      return this.items.size();
   }

   public String getItem(int index) {
      return (String)this.items.elementAt(index);
   }

   public synchronized void addItem(String item) {
      this.addItem(item, -1);
   }

   public synchronized void addItem(String item, int index) {
      if (index < -1 || index >= this.items.size()) {
         index = -1;
      }

      if (index == -1) {
         this.items.addElement(item);
      } else {
         this.items.insertElementAt(item, index);
      }

      ListPeer peer = (ListPeer)super.peer;
      if (peer != null) {
         peer.addItem(item, index);
      }

   }

   public synchronized void replaceItem(String newValue, int index) {
      this.delItem(index);
      this.addItem(newValue, index);
   }

   public synchronized void clear() {
      if (super.peer != null) {
         ((ListPeer)super.peer).clear();
      }

      this.items = new Vector();
      this.selected = new int[0];
   }

   public synchronized void delItem(int position) {
      this.delItems(position, position);
   }

   public synchronized void delItems(int start, int end) {
      for(int i = end; i >= start; --i) {
         this.items.removeElementAt(i);
      }

      if (super.peer != null) {
         ((ListPeer)super.peer).delItems(start, end);
      }

   }

   public synchronized int getSelectedIndex() {
      int[] sel = this.getSelectedIndexes();
      return sel.length == 1 ? sel[0] : -1;
   }

   public synchronized int[] getSelectedIndexes() {
      ListPeer peer = (ListPeer)super.peer;
      if (peer != null) {
         this.selected = peer.getSelectedIndexes();
      }

      return this.selected;
   }

   public synchronized String getSelectedItem() {
      int index = this.getSelectedIndex();
      return index < 0 ? null : this.getItem(index);
   }

   public synchronized String[] getSelectedItems() {
      int[] sel = this.getSelectedIndexes();
      String[] str = new String[sel.length];

      for(int i = 0; i < sel.length; ++i) {
         str[i] = this.getItem(sel[i]);
      }

      return str;
   }

   public synchronized void select(int index) {
      ListPeer peer = (ListPeer)super.peer;
      if (peer != null) {
         peer.select(index);
      } else {
         for(int i = 0; i < this.selected.length; ++i) {
            if (this.selected[i] == index) {
               return;
            }
         }

         if (!this.multipleSelections) {
            this.selected = new int[1];
            this.selected[0] = index;
         } else {
            int[] newsel = new int[this.selected.length + 1];
            System.arraycopy(this.selected, 0, newsel, 0, this.selected.length);
            newsel[this.selected.length] = index;
            this.selected = newsel;
         }
      }
   }

   public synchronized void deselect(int index) {
      ListPeer peer = (ListPeer)super.peer;
      if (peer != null) {
         peer.deselect(index);
      }

      for(int i = 0; i < this.selected.length; ++i) {
         if (this.selected[i] == index) {
            int[] newsel = new int[this.selected.length - 1];
            System.arraycopy(this.selected, 0, newsel, 0, i);
            System.arraycopy(this.selected, i + 1, newsel, i, this.selected.length - (i + 1));
            this.selected = newsel;
            return;
         }
      }

   }

   public synchronized boolean isSelected(int index) {
      int[] sel = this.getSelectedIndexes();

      for(int i = 0; i < sel.length; ++i) {
         if (sel[i] == index) {
            return true;
         }
      }

      return false;
   }

   public int getRows() {
      return this.rows;
   }

   public boolean allowsMultipleSelections() {
      return this.multipleSelections;
   }

   public void setMultipleSelections(boolean v) {
      if (v != this.multipleSelections) {
         this.multipleSelections = v;
         ListPeer peer = (ListPeer)super.peer;
         if (peer != null) {
            peer.setMultipleSelections(v);
         }
      }

   }

   public int getVisibleIndex() {
      return this.visibleIndex;
   }

   public void makeVisible(int index) {
      ListPeer peer = (ListPeer)super.peer;
      this.visibleIndex = index;
      if (peer != null) {
         peer.makeVisible(index);
      }

   }

   public Dimension preferredSize(int rows) {
      ListPeer peer = (ListPeer)super.peer;
      return peer != null ? peer.preferredSize(rows) : super.preferredSize();
   }

   public Dimension preferredSize() {
      return this.rows > 0 ? this.preferredSize(this.rows) : super.preferredSize();
   }

   public Dimension minimumSize(int rows) {
      ListPeer peer = (ListPeer)super.peer;
      return peer != null ? peer.minimumSize(rows) : super.minimumSize();
   }

   public Dimension minimumSize() {
      return this.rows > 0 ? this.minimumSize(this.rows) : super.minimumSize();
   }

   protected String paramString() {
      return super.paramString() + ",selected=" + this.getSelectedItem();
   }
}