Determining the currently pointed to item in a list

Question

I am working with lists. I have been able to determine the first and last position of items in my list. I am using getPostion and displaying item name through a

Answer 1

I'm not sure if this solves Your issue, but You can add

public fruit_trees current_tree;

field in ListForTrees class.

Then, You can easily add method showing next and moving item pointer to the next item in the list. Remembering the current item allows You to avoid browsing the whole list each time You want next tree from the list. The code can look like this:

public fruit_trees GetNextTree()
{
    //save currently pointed tree
    fruit_trees tree = this.current_tree;
    if (tree != null)
    {
        //move current_tree to the next tree, to be returned next time
        current_tree = current_tree.next_tree;
        //return saved tree object
    }
    return tree;
}

In order to make it work, You should also remember to initiate the value of current_tree with the first tree added to the list. You can also write some kind of ResetNextTreePointer() method pointing it back to the first tree in the list.

Some more suggestions to the code:

• I suppose it would be better to use properties for fields in your classes, so i.e. change

  public fruit_trees first_tree;
  

  into

  private fruit_trees first_tree;
  public fruit_trees First_tree { get { return first_tree; }
  

  as it would disable any class outside your class to modify those fields explicitly.

• This code:

  if (count == 0)
  {
      ...
  }
  else if (count != 0)
  {
      ...
  }
  

  can be changed into:

  if (count == 0)
  {
      ...
  }
  else
  {
      ...
  }