The NWTip class

using System;

using System.Collections;

using System.ComponentModel;

using System.Drawing;

using System.Windows.Forms;

using System.Runtime.InteropServices;

 

namespace WellFormed

{

  /// <summary>

  /// this extender-provider component also implements the custom interface

  /// IWndProcProvider so that it can interact with the ExtNativeWindow class. 

  /// </summary>

  [

  ProvideProperty("TipText","System.Windows.Forms.Control"),

  ProvideProperty("TipColor","System.Windows.Forms.Control"),

  ProvideProperty("TipTextColor","System.Windows.Forms.Control"),

  ProvideProperty("TipFont","System.Windows.Forms.Control"),

  ProvideProperty("TipBorderColor","System.Windows.Forms.Control")

  ]

  public class NWTip : Component, IExtenderProvider, IWndProcProvider

  {

 

    #region Interop

 

    [DllImport("User32.dll")]

    public extern static int ShowWindow( System.IntPtr hWnd, short cmdShow);

 

    [DllImport("User32.dll")]

    public extern static int ValidateRect( System.IntPtr hWnd, System.IntPtr rect);

 

    #endregion

 

    #region Fields

    //The NativeWindow member

    ExtNativeWindow _nw;

    //hash table that associates controls with tool tip data

    Hashtable _items=new Hashtable();

    //a reference to the current control. this is the control in which the cursor is hovering 

    Control _currentControl;

    //timer, used to remove the tool tip after a short interval. 

    Timer _killTimer;

    //A rectangle calculated from the size of the text. 

    Rectangle _tipRect;

    #endregion

 

    #region tooltip data container

 

    /// <summary>

    /// This class maintains all the properties associated with each control. 

    /// The hash table associates this class with the control using a reference as a key. 

    /// </summary>

    protected class tipData

    {

      string _text;

      public string Text

      {

        get{return _text;}

        set{_text=value;}

      }

 

      Color _tipColor=Color.Yellow;

      public Color TipColor

      {

        get{return _tipColor;}

        set{_tipColor=value;}

      }

 

      Color _textColor=Color.Black;

      public Color TextColor

      {

        get{return _textColor;}

        set{_textColor=value;}

      }

 

      Font _font=SystemInformation.MenuFont;

      public Font Font

      {

        get{return _font;}

        set{_font=value;}

      }

 

      Color _borderColor=Color.Black;

      public Color BorderColor

      {

        get{return _borderColor;}

        set{_borderColor=value;}

      }

 

    }

    #endregion

 

    #region Construction - disposal

 

    //when constructed, the class creates a new ExtNativeWindow

    public NWTip()

    {

      _nw=new ExtNativeWindow(this);

    }

 

    //The dispose method has to ensure that all the event handlers are removed from

    //the components that were extended.  

    protected override void Dispose(bool disposing)

    {

      if(disposing)

      {

        foreach(Control c in _items.Keys)

        {

          c.MouseHover-=new EventHandler(this.c_MouseHover);

          c.MouseLeave-=new EventHandler(this.c_MouseLeave);

        }

 

        this._items.Clear();

      }

      base.Dispose (disposing);

    }

    #endregion

 

    #region IExtenderProvider Members

 

    //This component can extend control. 

    public bool CanExtend(object extendee)

    {

      return extendee is Control;

    }

 

    //A utility routing to extract tipData from the hash table using the

    //Control  reference as a key. 

    protected tipData GetItem(Control c)

    {

      if(this._items.Contains(c))

        return (tipData)_items[c];

      tipData td=new tipData();

      _items[c]=td;

      c.MouseHover+=new EventHandler(c_MouseHover);

      c.MouseLeave+=new EventHandler(c_MouseLeave);

      return td;

    }

 

    /*

     * The following ten methods implement the set and get methods for each of the extended

     * properties that we provide to control based classes. 

     *

     */

 

    public void SetTipText(Control c, string value)

    {

      tipData td=GetItem(c);

      td.Text=value;

    }

 

    public void SetTipColor(Control c, Color value)

    {

      tipData td=GetItem(c);

      td.TipColor=value;

    }

    

    public void SetTipTextColor(Control c, Color value)

    {

      tipData td=GetItem(c);

      td.TextColor=value;

    }

 

    public void SetTipFont(Control c, Font value)

    {

      tipData td=GetItem(c);

      td.Font=value;

    }

 

    public void SetTipBorderColor(Control c, Color value)

    {

      tipData td=GetItem(c);

      td.BorderColor=value;

    }

 

    public string GetTipText(Control c)

    {

      tipData td=GetItem(c);

      return td.Text;

    }

 

    public Color GetTipColor(Control c)

    {

      tipData td=GetItem(c);

      return td.TipColor;

    }

    

    public Color GetTipTextColor(Control c)

    {

      tipData td=GetItem(c);

      return td.TextColor;

    }

 

    public Font GetTipFont(Control c)

    {

      tipData td=GetItem(c);

      return td.Font;

    }

 

    public Color GetTipBorderColor(Control c)

    {

      tipData td=GetItem(c);

      return td.BorderColor;

    }

 

    #endregion

 

    #region IWndProcProvider Members

 

    //Implements the IWndProcProvider interface which enables any class to host an ExtNativeWindow

    //Note. It is important to call the default WndProc for any messages not processed by this method. 

    void WellFormed.IWndProcProvider.WndProc(ref Message m, ExtNativeWindow defWndProcProvider)

    {

      switch(m.Msg)

      {

        case (int)WmDefs.WM_PAINT:

          PaintTooltip(ref m);

          break;

        default:

          defWndProcProvider.DefWndProc(ref m);

          break;

      }

    }

 

    #endregion

 

    #region Extended control mouse handlers

 

    //Handles the MouseHover event from the control been extended. 

    //this enables the extender-provider to know when the mouse cursor is in a control. 

    private void c_MouseHover(object sender, EventArgs e)

    {

      _currentControl=(Control)sender;

      if(_killTimer!=null)

      {

        _killTimer.Enabled=false;

        _killTimer.Dispose();

        _killTimer=null;

        _nw.DestroyHandle();

      }

      ShowTip();

    }

 

    //Handles the MouseLeave event from the control be extended.

    //This enables the extender-provider to know when the mouse cursor has left the

    //control and hence, when to destroy the tool tip window. 

    private void c_MouseLeave(object sender, EventArgs e)

    {

      if(sender == _currentControl)

      {

        _killTimer=new Timer();

        _killTimer.Interval=100;

        _killTimer.Tick+=new EventHandler(_killTimer_Tick);

        _killTimer.Enabled=true;

      }

    }

    #endregion

 

    #region Painting

 

    //A simple paint routine.  This fills the window with the background color,

    //paints the border, the text and finally validates the rectangle of the window. 

    protected void PaintTooltip(ref Message m)

    {

      tipData td=this.GetItem(this._currentControl);

      Graphics g=Graphics.FromHwnd(_nw.Handle);

      g.Clear(td.TipColor);

      Pen p=new Pen(td.BorderColor,_tipRect.Height/100);

      g.DrawRectangle(p,0,0,_tipRect.Width-1,_tipRect.Height-1);

      p.Dispose();

      SolidBrush sb=new SolidBrush(td.TextColor);

      g.DrawString(td.Text,td.Font,sb,_tipRect.Width/20,_tipRect.Height/20,StringFormat.GenericTypographic);

      sb.Dispose();

      g.Dispose();

      m.Result=IntPtr.Zero;

      ValidateRect(m.HWnd,IntPtr.Zero);

    }

    #endregion

 

    #region low-level window management

 

    //The windows creation parameters. 

    protected CreateParams CreateParams

    {

      get

      {

        System.Windows.Forms.CreateParams cp=new System.Windows.Forms.CreateParams();

        unchecked

        {

          cp.Style = (int)WindowStyles.WS_POPUP;

        }

        cp.ClassStyle=(int)ClassStyles.CS_OWNDC | (int)ClassStyles.CS_HREDRAW | (int)ClassStyles.CS_VREDRAW;

        cp.ExStyle=(int)WindowStyles.WS_EX_TOPMOST;

        cp.ClassName="tooltips_class32";

        cp.X=0;

        cp.Y=0;

        cp.Height=0;

        cp.Width=0;

        cp.Parent=System.IntPtr.Zero;

 

        cp.Caption=null;

        return cp;

      }

    }

 

    //This handles the time out from the timer which is set whenever the cursor leaves a control.

    //It destroys the tool tip window. 

    private void _killTimer_Tick(object sender, EventArgs e)

    {

      ((Timer)sender).Enabled=false;

      _nw.DestroyHandle();

    }

 

    //Called by the mouse hover Handler to display the tool tip window.

    private void ShowTip()

    {

      CreateParams cp=this.CreateParams;

      Graphics g = Graphics.FromHwnd(IntPtr.Zero);

      tipData td = (tipData)_items[this._currentControl];

      SizeF sf=g.MeasureString(td.Text,td.Font,1024,StringFormat.GenericTypographic);

      Point position =Control.MousePosition;

      Rectangle rc=new Rectangle(position.X,(int)(position.Y+SystemInformation.CursorSize.Height),(int)sf.Width,(int)sf.Height);

      rc.Inflate(rc.Width/10,rc.Height/10);

      _tipRect=rc;

      if(rc.Right>SystemInformation.VirtualScreen.Right)

        rc.Offset(-(rc.Right-SystemInformation.VirtualScreen.Right),0);

      if(rc.Bottom>SystemInformation.VirtualScreen.Bottom)

        rc.Offset(0,-((rc.Bottom-SystemInformation.VirtualScreen.Bottom)+rc.Height+SystemInformation.CursorSize.Height));

      if(rc.Left<10)

        rc.X=10;

      cp.X=rc.X;

      cp.Y=rc.Y;

      cp.Width=rc.Width;

      cp.Height=rc.Height;

      _nw.CreateHandle(cp);

      ShowWindow(_nw.Handle,(short)WellFormed.ShowWindow.SW_SHOWNOACTIVATE);

    }

    #endregion

 

  }

}

Imports System

Imports System.Collections

Imports System.ComponentModel

Imports System.Drawing

Imports System.Windows.Forms

Imports System.Runtime.InteropServices

 

Class resfinder

 

End Class

 

Namespace WellFormed

 

  '' <summary>

  '' me extender-provider component also implements the custom interface

  '' IWndProcProvider so that it can interact with the ExtNativeWindow class.  

  '' </summary>

  < _

  ProvideProperty("TipText", "System.Windows.Forms.Control"), _

  ProvideProperty("TipColor", "System.Windows.Forms.Control"), _

  ProvideProperty("TipTextColor", "System.Windows.Forms.Control"), _

  ProvideProperty("TipFont", "System.Windows.Forms.Control"), _

  ProvideProperty("TipBorderColor", "System.Windows.Forms.Control"), _

  ToolboxBitmap(GetType(resfinder), "NWTip.NWTip.bmp") _

  > _

     Public Class NWTip

    Inherits Component

    Implements IExtenderProvider, IWndProcProvider

 

#Region "Interop"

 

    <DllImport("User32.dll")> _

    Public Shared Function ShowWindow(ByVal hWnd As System.IntPtr, ByVal cmdShow As Short) As Integer

    End Function

 

    <DllImport("User32.dll")> _

    Public Shared Function ValidateRect(ByVal hWnd As System.IntPtr, ByVal rect As System.IntPtr) As Integer

    End Function

 

#End Region

 

#Region "Fields"

    'The NativeWindow member

    Private nw As ExtNativeWindow

    'hash table that associates controls with tool tip data

    Private items As New Hashtable

    'a reference to the current control. me is the control in which the cursor is hovering 

    Private currentControl As Control

    'timer, used to remove the tool tip after a short interval. 

    Private killTimer As Timer

    'A rectangle calculated from the size of the text. 

    Private tipRect As Rectangle

#End Region

 

#Region "tooltip data container"

 

    '' <summary>

    '' This class maintains all the properties associated with each control. 

    '' The hash table associates me class with the control imports a reference as a key. 

    '' </summary>

    Protected Class tipData

 

      Private _text As String

      Public Property Text() As String

        Get

          Return _text

        End Get

        Set(ByVal Value As String)

          _text = Value

        End Set

      End Property

 

      Private _tipColor As Color = Color.Yellow

      Public Property TipColor() As Color

        Get

          Return _tipColor

        End Get

        Set(ByVal Value As Color)

          _tipColor = Value

        End Set

      End Property

 

      Private _textColor As Color = Color.Black

      Public Property TextColor() As Color

        Get

          Return _textColor

        End Get

        Set(ByVal Value As Color)

          _textColor = Value

        End Set

      End Property

 

      Private _font As Font = SystemInformation.MenuFont

      Public Property Font() As Font

        Get

          Return _font

        End Get

        Set(ByVal Value As Font)

          _font = Value

        End Set

      End Property

 

      Private _borderColor As Color = Color.Black

      Public Property BorderColor() As Color

        Get

          Return _borderColor

        End Get

        Set(ByVal Value As Color)

          _borderColor = Value

        End Set

      End Property

 

    End Class

#End Region

 

#Region "Construction - disposal"

 

    'when constructed, the class creates a new ExtNativeWindow

    Public Sub New()

      nw = New ExtNativeWindow(Me)

    End Sub

 

    'The dispose method has to ensure that all the event handlers are removed from

    'the components that were extended.  

    Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)

      If (disposing) Then

        Dim c As Control

 

        For Each c In items.Keys

          RemoveHandler c.MouseHover, AddressOf Me.cMouseHover

          RemoveHandler c.MouseLeave, AddressOf Me.cMouseLeave

        Next

 

        Me.items.Clear()

      End If

      MyBase.Dispose(disposing)

    End Sub

#End Region

 

#Region "IExtenderProvider Members"

 

    'This component can extend control. 

    Public Function CanExtend(ByVal extendee As [Object]) As Boolean Implements IExtenderProvider.CanExtend

      If TypeOf extendee Is Control Then

        Return True

      Else

        Return False

      End If

    End Function

 

    'A utility routing to extract tipData from the hash table imports the

    'Control  reference as a key. 

    Protected Function GetItem(ByVal c As Control) As tipData

      If (Me.items.Contains(c)) Then

        Return CType(items(c), tipData)

      End If

      Dim td As New tipData

      items(c) = td

      AddHandler c.MouseHover, AddressOf cMouseHover

      AddHandler c.MouseLeave, AddressOf cMouseLeave

      Return td

    End Function

 

    '*

    '* The following ten methods implement the set and get methods for each of the extended

    '* properties that we provide to control based classes. 

    '*

    '*

 

    Public Sub SetTipText(ByVal c As Control, ByVal value As String)

      Dim td As tipData = GetItem(c)

      td.Text = value

    End Sub

 

    Public Sub SetTipColor(ByVal c As Control, ByVal value As Color)

      Dim td As tipData = GetItem(c)

      td.TipColor = value

    End Sub

 

    Public Sub SetTipTextColor(ByVal c As Control, ByVal value As Color)

      Dim td As tipData = GetItem(c)

      td.TextColor = value

    End Sub

 

    Public Sub SetTipFont(ByVal c As Control, ByVal value As Font)

      Dim td As tipData = GetItem(c)

      td.Font = value

    End Sub

 

    Public Sub SetTipBorderColor(ByVal c As Control, ByVal value As Color)

      Dim td As tipData = GetItem(c)

      td.BorderColor = value

    End Sub

 

    Public Function GetTipText(ByVal c As Control) As String

      Dim td As tipData = GetItem(c)

      Return td.Text

    End Function

 

    Public Function GetTipColor(ByVal c As Control) As Color

      Dim td As tipData = GetItem(c)

      Return td.TipColor

    End Function

 

    Public Function GetTipTextColor(ByVal c As Control) As Color

      Dim td As tipData = GetItem(c)

      Return td.TextColor

    End Function

 

    Public Function GetTipFont(ByVal c As Control) As Font

      Dim td As tipData = GetItem(c)

      Return td.Font

    End Function

 

    Public Function GetTipBorderColor(ByVal c As Control) As Color

      Dim td As tipData = GetItem(c)

      Return td.BorderColor

    End Function

 

#End Region

 

#Region "IWndProcProvider Members"

 

    'Implements the IWndProcProvider interface which enables any class to host an ExtNativeWindow

    'Note. It is important to call the default WndProc for any messages not processed by me method. 

    Public Sub WndProc(ByRef m As Message, ByVal defWndProcProvider As ExtNativeWindow) Implements IWndProcProvider.WndProc

      Select Case m.Msg

        Case WmDefs.WM_PAINT

          PaintTooltip(m)

        Case Else

          defWndProcProvider.DefWndProc(m)

      End Select

    End Sub

 

#End Region

 

#Region "Extended control mouse handlers"

 

    'Handles the MouseHover event from the control been extended. 

    'me enables the extender-provider to know when the mouse cursor is in a control. 

    Private Sub cMouseHover(ByVal sender As Object, ByVal e As EventArgs)

      currentControl = CType(sender, Control)

      If (Not killTimer Is Nothing) Then

        killTimer.Enabled = False

        killTimer.Dispose()

        killTimer = Nothing

        nw.DestroyHandle()

      End If

      ShowTip()

    End Sub

 

    'Handles the MouseLeave event from the control be extended.

    'This enables the extender-provider to know when the mouse cursor has left the

    'control and hence, when to destroy the tool tip window. 

    Private Sub cMouseLeave(ByVal sender As Object, ByVal e As EventArgs)

      If (sender Is currentControl) Then

        killTimer = New Timer

        killTimer.Interval = 100

        AddHandler killTimer.Tick, AddressOf killTimerTick

        killTimer.Enabled = True

      End If

    End Sub

#End Region

 

#Region "Painting"

 

    'A simple paint routine.  This fills the window with the background color,

    'paints the border, the _text and finally validates the rectangle of the window. 

    Protected Sub PaintTooltip(ByRef m As Message)

      Dim td As tipData = Me.GetItem(Me.currentControl)

      Dim g As Graphics = Graphics.FromHwnd(nw.Handle)

      g.Clear(td.TipColor)

      Dim p As New Pen(td.BorderColor, tipRect.Height / 100)

      g.DrawRectangle(p, 0, 0, tipRect.Width - 1, tipRect.Height - 1)

      p.Dispose()

      Dim sb As New SolidBrush(td.TextColor)

      g.DrawString(td.Text, td.Font, sb, tipRect.Width / 10, tipRect.Height / 20, StringFormat.GenericTypographic)

      sb.Dispose()

      g.Dispose()

      m.Result = IntPtr.Zero

      ValidateRect(m.HWnd, IntPtr.Zero)

    End Sub

#End Region

 

#Region "low-level window management"

 

    'The windows creation parameters. 

    Protected ReadOnly Property CreateParams() As CreateParams

      Get

        Dim cp As New System.Windows.Forms.CreateParams

        cp.Style = CInt(WindowStyles.WS_POPUP)

        cp.ClassStyle = CInt(ClassStyles.CS_OWNDC Or ClassStyles.CS_HREDRAW Or ClassStyles.CS_VREDRAW)

        cp.ExStyle = CInt(WindowStyles.WS_EX_TOPMOST)

        cp.ClassName = "tooltips_class32"

        cp.X = 0

        cp.Y = 0

        cp.Height = 0

        cp.Width = 0

        cp.Parent = System.IntPtr.Zero

 

        cp.Caption = Nothing

        Return cp

      End Get

    End Property

 

    'This handles the time out from the timer which is set whenever the cursor leaves a control.

    'It destroys the tool tip window. 

    Private Sub killTimerTick(ByVal sender As Object, ByVal e As EventArgs)

      CType(sender, Timer).Enabled = False

      nw.DestroyHandle()

    End Sub

 

    'Called by the mouse hover Handler to display the tool tip window.

    Private Sub ShowTip()

      Dim cp As CreateParams = Me.CreateParams

      Dim g As Graphics = Graphics.FromHwnd(IntPtr.Zero)

      Dim td As tipData = CType(items(Me.currentControl), tipData)

      Dim sf As SizeF = g.MeasureString(td.Text, td.Font, 1024, StringFormat.GenericTypographic)

      Dim position As Point = Control.MousePosition

      Dim rc As New Rectangle(position.X, CInt((position.Y + SystemInformation.CursorSize.Height)), CInt(sf.Width), CInt(sf.Height))

      rc.Inflate(rc.Width / 10, rc.Height / 10)

      tipRect = rc

      If (rc.Right > SystemInformation.VirtualScreen.Right) Then

        rc.Offset(-(rc.Right - SystemInformation.VirtualScreen.Right), 0)

      End If

      If (rc.Bottom > SystemInformation.VirtualScreen.Bottom) Then

        rc.Offset(0, -((rc.Bottom - SystemInformation.VirtualScreen.Bottom) + rc.Height + SystemInformation.CursorSize.Height))

      End If

      If (rc.Left < 10) Then

        rc.X = 10

      End If

      cp.X = rc.X

      cp.Y = rc.Y

      cp.Width = rc.Width

      cp.Height = rc.Height

      nw.CreateHandle(cp)

      ShowWindow(nw.Handle, CType(WellFormed.ShowWindow.SW_SHOWNOACTIVATE, Short))

    End Sub

#End Region

 

  End Class

End Namespace