ext/Aga.Controls/Tree/NodeControls/EditableControl.cs

using System;
using System.Collections.Generic;
using System.Text;
using System.Windows.Forms;
using System.Drawing;
using System.ComponentModel;

namespace Aga.Controls.Tree.NodeControls
{
	public abstract class EditableControl : InteractiveControl
	{
		private Timer _timer;
		private bool _editFlag;

		#region Properties

		private TreeNodeAdv _editNode;
		protected TreeNodeAdv EditNode
		{
			get { return _editNode; }
		}

		private Control _editor;
		protected Control CurrentEditor
		{
			get { return _editor; }
		}

		private bool _editOnClick = false;
		[DefaultValue(false)]
		public bool EditOnClick
		{
			get { return _editOnClick; }
			set { _editOnClick = value; }
		}
		
		#endregion

		protected EditableControl()
		{
			_timer = new Timer();
			_timer.Interval = 500;
			_timer.Tick += new EventHandler(TimerTick);
		}

		private void TimerTick(object sender, EventArgs e)
		{
			_timer.Stop();
			if (_editFlag)
				BeginEditByUser();
			_editFlag = false;
		}

		public void SetEditorBounds(EditorContext context)
		{
			Size size = CalculateEditorSize(context);
			context.Editor.Bounds = new Rectangle(context.Bounds.X, context.Bounds.Y,
				Math.Min(size.Width, context.Bounds.Width), context.Bounds.Height);
		}

		protected abstract Size CalculateEditorSize(EditorContext context);

		protected virtual bool CanEdit(TreeNodeAdv node)
		{
			return (node.Tag != null) && IsEditEnabled(node);
		}

		protected void BeginEditByUser()
		{
			if (EditEnabled)
				BeginEdit();
		}

		public void BeginEdit()
		{
			if (Parent.CurrentNode != null && CanEdit(Parent.CurrentNode))
			{
				CancelEventArgs args = new CancelEventArgs();
				OnEditorShowing(args);
				if (!args.Cancel)
				{
          Control editor = CreateEditor(Parent.CurrentNode);
          if (null != editor)
          {
            _editor = editor;
            _editor.Validating += new CancelEventHandler(EditorValidating);
            _editor.KeyDown += new KeyEventHandler(EditorKeyDown);
            _editNode = Parent.CurrentNode;
            Parent.DisplayEditor(_editor, this);
          }
				}
			}
		}

		// !!! changed by mzinner@mysql.com
    // ml: act only for key input if the event wasn't handled already.
		protected virtual void EditorKeyDown(object sender, KeyEventArgs e)
		{
      if (!e.Handled)
      {
        if (e.KeyCode == Keys.Escape)
          EndEdit(false);
        else if (e.KeyCode == Keys.Enter)
          EndEdit(true);
      }
		}

		private void EditorValidating(object sender, CancelEventArgs e)
		{
			ApplyChanges();
		}

		internal void HideEditor(Control editor)
		{
			editor.Validating -= EditorValidating;
			editor.Parent = null;
			editor.Dispose();
			_editNode = null;
      _editor = null;
			OnEditorHidden();
		}

		public void EndEdit(bool applyChanges)
		{
			if (!applyChanges && _editor != null)
				_editor.Validating -= EditorValidating;
			Parent.Focus();
      Parent.Cursor = Cursors.Default;
      Cursor.Show();
		}

		public virtual void UpdateEditor(Control control)
		{
		}

		public virtual void ApplyChanges()
		{
			try
			{
				DoApplyChanges(_editNode, _editor);
			}
			catch (ArgumentException ex)
			{
				MessageBox.Show(ex.Message, "Value is not valid", MessageBoxButtons.OK, MessageBoxIcon.Warning);
			}
		}

		protected abstract void DoApplyChanges(TreeNodeAdv node, Control editor);

		protected abstract Control CreateEditor(TreeNodeAdv node);

		public override void MouseDown(TreeNodeAdvMouseEventArgs args)
		{
			_editFlag = (!EditOnClick && args.Button == MouseButtons.Left 
				&& args.ModifierKeys == Keys.None && args.Node.IsSelected);
		}

		public override void MouseUp(TreeNodeAdvMouseEventArgs args)
		{
			if (EditOnClick && args.Button == MouseButtons.Left && args.ModifierKeys == Keys.None)
			{
        if (_editor != null)
          EndEdit(true);

				Parent.ItemDragMode = false;
				BeginEdit();
				args.Handled = true;
			}
			else if (_editFlag && args.Node.IsSelected)
				_timer.Start();
		}

		public override void MouseDoubleClick(TreeNodeAdvMouseEventArgs args)
		{
			_editFlag = false;
			_timer.Stop();
		}

		protected override void Dispose(bool disposing)
		{
			base.Dispose(disposing);
			if (disposing)
				_timer.Dispose();
		}

		#region Events

		public event CancelEventHandler EditorShowing;
		protected void OnEditorShowing(CancelEventArgs args)
		{
			if (EditorShowing != null)
				EditorShowing(this, args);
		}

		public event EventHandler EditorHided;
		protected void OnEditorHidden()
		{
			if (EditorHided != null)
				EditorHided(this, EventArgs.Empty);
		}

		#endregion
	}
}