javax.swing.tree.DefaultMutableTreeNode#getChildAfter ( )源码实例Demo

/**
 * Removes empty categories. This method can create some new empty
 * categories!
 * 
 * @param current
 *            the current node
 * @return true if an empty category was removed
 */
private boolean removeEmptyCategories(DefaultMutableTreeNode current) {
	if (!current.children().hasMoreElements()) {
		return false;
	}

	TreeNode node = current.getFirstChild();
	boolean removed = false;
	while (node != null) {
		DefaultMutableTreeNode n = (DefaultMutableTreeNode) node;
		node = current.getChildAfter(n);

		if (n.isLeaf()) {
			if (n instanceof CategoryTreeNode && n.getChildCount() == 0) {
				DefaultMutableTreeNode parent = (DefaultMutableTreeNode) n.getParent();
				parent.remove(n);
				removed = true;
			}
		} else {
			removed = removed || removeEmptyCategories(n);
		}
	}
	return removed;
}
 

public void next() {
	DefaultMutableTreeNode list = (DefaultMutableTreeNode) playingSong
			.getParent();
	SongNode songNode = null;

	if (!IsPlayNextSong) {
		songNode = (SongNode) list.getChildBefore(playingSong);

	} else {
		songNode = (SongNode) list.getChildAfter(playingSong);
	}
	if (songNode == null) {
		IsPause = false;

		return;
	}
	// 在当前所在的歌曲列表路径中加入待播放的歌曲 形成待播放歌曲的路径
	TreePath songPath = currentListPath.pathByAddingChild(songNode);
	tree.setSelectionPath(songPath);

	if (songNode.getHTTPFlag())
		load(songNode, songNode.getDataURL());
	else
		load(songNode);
}
 

private void cycle() {
	DefaultMutableTreeNode list = (DefaultMutableTreeNode) playingSong
			.getParent();
	SongNode songNode = null;

	songNode = (SongNode) list.getChildAfter(playingSong);

	if (songNode == null) {
		songNode = (SongNode) list.getFirstChild();
	}

	// 在当前所在的歌曲列表路径中加入待播放的歌曲 形成待播放歌曲的路径
	TreePath songPath = currentListPath.pathByAddingChild(songNode);
	tree.setSelectionPath(songPath);

	if (songNode.getHTTPFlag())
		load(songNode, songNode.getDataURL());
	else
		load(songNode);

}
 

private void removeRows() {
  TreeNode toSelect = null;

  TreePath[] paths = myTree.getSelectionPaths();
  if (paths == null) return;

  for (TreePath path : paths) {
    DefaultMutableTreeNode node = (DefaultMutableTreeNode)path.getLastPathComponent();
    Object o = node.getUserObject();
    if (o instanceof TemplateGroup) {
      //noinspection SuspiciousMethodCalls
      myTemplateGroups.remove(o);
      removeNodeFromParent(node);
    } else if (o instanceof TemplateImpl) {
      TemplateImpl template = (TemplateImpl)o;
      TemplateGroup templateGroup = getTemplateGroup(template.getGroupName());
      if (templateGroup != null) {
        templateGroup.removeElement(template);
        DefaultMutableTreeNode parent = (DefaultMutableTreeNode)node.getParent();

        if (templateGroup.getElements().isEmpty()) {
          myTemplateGroups.remove(templateGroup);
          removeNodeFromParent(parent);
        } else {
          toSelect = parent.getChildAfter(node);
          removeNodeFromParent(node);
        }
      }
    }
  }

  if (toSelect instanceof DefaultMutableTreeNode) {
    setSelectedNode((DefaultMutableTreeNode)toSelect);
  }
}
 

private static int getIndexToInsert(DefaultMutableTreeNode parent, String key) {
  if (parent.getChildCount() == 0) return 0;

  int res = 0;
  for (DefaultMutableTreeNode child = (DefaultMutableTreeNode)parent.getFirstChild();
       child != null;
       child = (DefaultMutableTreeNode)parent.getChildAfter(child)) {
    Object o = child.getUserObject();
    String key1 = o instanceof TemplateImpl ? ((TemplateImpl)o).getKey() : ((TemplateGroup)o).getName();
    if (key1.compareToIgnoreCase(key) > 0) return res;
    res++;
  }
  return res;
}