treeelement.cs

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			}
		}

		/// <summary>
		/// Gets or sets the default CssClass for the element when OnMouseOver client event occure.
		/// </summary>
		/// <author>
		/// Created by Iulian Iuga; 26 January, 2003
		/// </author>
		[
		Bindable( true ),
		DefaultValue( "" ),
		PersistenceMode( PersistenceMode.Attribute )
		]
		public string CssClassOver
		{
			get {
				string _cssClassOver = (string) ViewState["CssClassOver"];
				return ( ( _cssClassOver == null ) ? String.Empty : _cssClassOver );
			}
			set {
				ViewState["CssClassOver"] = value;
			}
		}

		/// <summary>
		/// Gets or sets the image index to be showen before the element in the tree.
		/// </summary>
		/// <author>
		/// Created by Iulian Iuga; 2 February, 2003
		/// </author>
		[
		Bindable( true ),
		DefaultValue( -1 ),
		PersistenceMode( PersistenceMode.Attribute )
		]
		public int ImageIndex 
		{
			get {
				object _index = ViewState["ImageIndex"];
				return( ( _index == null ) ? -1 : (int)_index );
			}
			set {
				ViewState["ImageIndex"] = value;
			}
		}

		#endregion

		#region TreeElement private properties

		/// <summary>
		/// Gets the writer object for the tree element.
		/// </summary>
		/// <author>
		/// Created by Iulian Iuga; 04 January, 2003
		/// </author>
		private ITreeElementWriter ElementWriter
		{
			get {
				return new TreeElementWriter();
			}
		}

		#endregion

		#region TreeElement internal properties

		/// <summary>
		/// Internaly gets the control StateBag object. The StateBag object is case sensitive.
		/// </summary>
		/// <author>
		/// Created by Iulian Iuga; 01 January, 2003
		/// </author>
		internal StateBag ViewState 
		{
			get {
				if( _state == null ) 
				{
					_state = new StateBag( true );
					if( ((IStateManager)this).IsTrackingViewState )
						((IStateManager)_state).TrackViewState();
				}
				return _state;
			}
		}

		/// <summary>
		/// Internaly gets or sets the type of the element. (i.e. design time or run time added)
		/// </summary>
		/// <author>
		/// Created by Iulian Iuga; 19 January, 2003
		/// </author>
		internal _ElementType ElementType
		{
			get {
				return _elementType;
			}
			set {
				_elementType = value;
			}
		}

		#endregion

		#region TreeElement public methods

		/// <summary>
		/// 
		/// </summary>
		/// <author>
		/// Created by Iulian Iuga; 27 December, 2002
		/// </author>
		public TreeElement()
		{}

		/// <summary>
		/// 
		/// </summary>
		/// <author>
		/// Created by Iulian Iuga; 28 December, 2002
		/// </author>
		public TreeElement( string text )
		{
			if( text == null )
				throw new ArgumentNullException();

			((IStateManager)this).TrackViewState();
			Text = text;
		}

		/// <summary>
		/// 
		/// </summary>
		/// <author>
		/// Created by Iulian Iuga; 18 January, 2003
		/// </author>
		public TreeElement( string text, string navigateUrl )
		{
			if( text == null || navigateUrl == null )
				throw new ArgumentNullException();

			((IStateManager)this).TrackViewState();
			Text = text;
			NavigateUrl = navigateUrl;
		}

		/// <summary>
		/// Expand current element, it has effect only if it has elements.
		/// </summary>
		/// <author>
		/// Created by Iulian Iuga; 01 January, 2003
		/// </author>
		public void Expand()
		{
			if( HasElements )
			{
				ViewState["IsExpanded"] = true;
				TreeWeb.OnExpand( new TreeWeb.TreeWebEventArgs( this ) );
			}
		}

		/// <summary>
		/// Collapse current element, it has effect only if it has elements.
		/// </summary>
		/// <author>
		/// Created by Iulian Iuga; 01 January, 2003
		/// </author>
		public void Collapse()
		{
			if( HasElements )
			{
				ViewState["IsExpanded"] = false;
				TreeWeb.OnCollapse( new TreeWeb.TreeWebEventArgs( this ) );
			}
		}

		/// <summary>
		/// Finds a specified child element of current tree element.
		/// 
		/// Note: The search algorithm can be optimized.
		/// </summary>
		/// <param name="ID">The searched element id.</param>
		/// <returns>The child element coresponding to the ID parameter value.</returns>
		/// <author>
		/// Created by Iulian Iuga; 04 January, 2003
		/// </author>
		public TreeElement FindElement( string ID )
		{
			// TODO: optimize the search algorithm.

			foreach( TreeElement element in Elements )
			{
				if( element.ID == ID )
					return element;
			}

			foreach( TreeElement element in Elements )
			{
				TreeElement _found = element.FindElement( ID );
				if( _found != null )
					return _found;
			}

			return null;
		}

		/// <summary>
		/// 
		/// </summary>
		/// <param name="writer"></param>
		/// <author>
		/// Created by Iulian Iuga; 27 December, 2002
		/// </author>
		public virtual void Render( HtmlTextWriter writer ) //, TreeRenderState treeState
		{
			ElementWriter.RenderElement( writer, this );
		}

		/// <summary>
		/// (IStateManager.SaveViewState)
		/// Saves the changes of TreeElement's view state to an Object.
		/// </summary>
		/// <returns></returns>
		/// <author>
		/// Created by Iulian Iuga; 01 January, 2003
		/// </author>
		object IStateManager.SaveViewState()
		{
			// save _state state
			object _stateState = null;
			if( _state != null ) 
				_stateState = ((IStateManager)_state).SaveViewState();

			// save _elements state
			object _elementsState = null;
			if( _elements != null ) 
				_elementsState = ((IStateManager)_elements).SaveViewState();

			if ( _stateState == null && _elementsState == null) 
				return null;

			object[] _newState = new object[2];

			_newState[0] = _stateState;
			_newState[1] = _elementsState;

			return _newState;
		}

		/// <summary>
		/// (IStateManager.TrackViewState)
		/// Instructs the TreeElement to track changes to its view state.
		/// </summary>
		/// <author>
		/// Created by Iulian Iuga; 01 January, 2003
		/// </author>
		void IStateManager.TrackViewState()
		{
			_marked = true;

			if( _state != null )
				((IStateManager)_state).TrackViewState();
			if( _elements != null ) 
				((IStateManager)_elements).TrackViewState();
		}

		/// <summary>
		/// (IStateManager.LoadViewState)
		/// Loads the TreeElement's previously saved view state.
		/// </summary>
		/// <author>
		/// Created by Iulian Iuga; 01 January, 2003
		/// </author>
		void IStateManager.LoadViewState( object state )
		{
			if( state != null )
			{
				object[] _newState = (object[])state;

				if( _newState[0] != null )
					((IStateManager)ViewState).LoadViewState( _newState[0] );
				if( _newState[1] != null )
					((IStateManager)Elements).LoadViewState( _newState[1] );
			}
		}

		/// <summary>
		/// 
		/// </summary>
		/// <author>
		/// Created by Iulian Iuga; 01 January, 2003
		/// </author>
		bool IStateManager.IsTrackingViewState 
		{
			get {
				return _marked;
			}
		}

		#endregion

		#region TreeElement internal methods

		/// <summary>
		/// Internaly sets the element id.
		/// </summary>
		/// <param name="elementID"></param>
		/// <author>
		/// Created by Iulian Iuga; 01 January, 2003
		/// </author>
		internal void SetElementID( string elementID )
		{
			_id = elementID;
		}

		/// <summary>
		/// Internaly sets the node parent.
		/// </summary>
		/// <param name="parent"></param>
		/// <author>
		/// Created by Iulian Iuga; 01 January, 2003
		/// </author>
		internal void SetParent( TreeElement parent ) 
		{
			_parent = parent;
		}

		/// <summary>
		/// Internaly sets the TreeWeb control which contains the node.
		/// </summary>
		/// <param name="treeWeb"></param>
		/// <author>
		/// Created by Iulian Iuga; 01 January, 2003
		/// </author>
		internal void SetTreeWeb( TreeWeb treeWeb ) 
		{
			_treeWeb = treeWeb;
		}

		/// <summary>
		/// Internaly sets the level where the node is in the tree.
		/// </summary>
		/// <param name="level"></param>
		/// <author>
		/// Created by Iulian Iuga; 04 January, 2003
		/// </author>
		internal void SetLevel( int level ) 
		{
			_level = level;
		}

		#endregion

		#region TreeElement private methods


		#endregion	
	}

}