InkPicture.NewInAirPackets Event
Occurs when the InkPicture control detects an in-air packet.
Namespace: Microsoft.Ink
Assembly: Microsoft.Ink (in microsoft.ink.dll)
Syntax
'Declaration
Public Event NewInAirPackets As InkCollectorNewInAirPacketsEventHandler
'Usage
Dim instance As InkPicture
Dim handler As InkCollectorNewInAirPacketsEventHandler
AddHandler instance.NewInAirPackets, handler
public event InkCollectorNewInAirPacketsEventHandler NewInAirPackets
public:
event InkCollectorNewInAirPacketsEventHandler^ NewInAirPackets {
void add (InkCollectorNewInAirPacketsEventHandler^ value);
void remove (InkCollectorNewInAirPacketsEventHandler^ value);
}
/** @event */
public void add_NewInAirPackets (InkCollectorNewInAirPacketsEventHandler value)
/** @event */
public void remove_NewInAirPackets (InkCollectorNewInAirPacketsEventHandler value)
In JScript, you can handle the events defined by a class, but you cannot define your own.
Not applicable.
Remarks
This event occurs when a user moves a cursor within the physical detection range (proximity) of the tablet context while the cursor is within the InkPicture control's window or the user moves a mouse within the InkPicture control's associated window.
NewInAirPackets events are generated rapidly, and the event handler must be fast or performance suffers
The event handler receives an argument of type InkCollectorNewInAirPacketsEventArgs that contains data about this event.
When you create an InkCollectorNewInAirPacketsEventHandler delegate, you identify the method that handles the event. To associate the event with your event handler, add an instance of the delegate to the event. The event handler is called whenever the event occurs, unless you remove the delegate. For performance reasons, the default event interest is off but is turned on automatically if you add an event handler.
The NewInAirPackets event fires even when in select or erase mode, not only when inserting ink. This requires that you monitor the editing mode (which you are responsible for setting) and be aware of the mode before interpreting the event. The advantage of this requirement is greater freedom to innovate on the platform through greater awareness of platform events.
Example
This C# example draws a rectangle on an InkPicture control, theInkPicture. The NewInAirPackets event handler outlines the rectangle with a bold outline when theInkPicture detects in-air packets within the bounds of the rectangle and with a narrow outline when theInkPicture detects in-air packets outside the bounds of the rectangle. This demonstrates how to use the packet events to control application behaviors.
[C#]
using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;
using Microsoft.Ink;
namespace CSInAirPacketEvents
{
public class Form1 : System.Windows.Forms.Form
{
//...
int indexX, indexY;
Rectangle rectInterest;
bool thickBorder;
public Form1()
{
//...
//Initialize the InkPicture control.
theInkPicture.InkEnabled = true;
//Initialize the target rectangle
rectInterest = new Rectangle(40, 40, 200, 80);
thickBorder = false;
//Save the X and Y data locations within the packet data.
GetXYIndexes(ref indexX, ref indexY);
//Add the event handler for in-air packets
theInkPicture.NewInAirPackets += new InkCollectorNewInAirPacketsEventHandler(NewInAirPackets_Event);
}
//...
private void GetXYIndexes(ref int theXIndex, ref int theYIndex)
{
// Get the indexes of the X and Y data within the raw
// packet data array.
Guid [] theGuids = theInkPicture.DesiredPacketDescription;
for (int i = 0; i < theGuids.Length; i++)
{
if (theGuids[i].Equals(PacketProperty.X))
theXIndex = i;
if (theGuids[i].Equals(PacketProperty.Y))
theYIndex = i;
}
}
private void NewInAirPackets_Event(object sender, InkCollectorNewInAirPacketsEventArgs e)
{
Graphics g = this.CreateGraphics();
Point [] pt = new Point [1];
pt[0].X = e.PacketData[indexX];
pt[0].Y = e.PacketData[indexY];
theInkPicture.Renderer.InkSpaceToPixel(g, ref pt);
// The event may return with data for multiple packets.
// To simplify things, we'll only look at the first.
if (rectInterest.Contains(pt[0].X, pt[0].Y))
{
if (!thickBorder)
{
thickBorder = true;
Refresh();
}
}
else
{
if (thickBorder)
{
thickBorder = false;
Refresh();
}
}
}
private void Form1_Paint(object sender, System.Windows.Forms.PaintEventArgs e)
{
Graphics g = e.Graphics;
Pen thePen = new Pen(Color.Black, 2);
if (thickBorder)
thePen.Width = 5;
g.DrawRectangle(thePen, rectInterest);
}
}
}
This Microsoft® Visual Basic® .NET event handler outlines the rectangle with a bold outline when theInkPicture detects in-air packets within the bounds of the rectangle and with a narrow outline when theInkPicture detects in-air packets outside the bounds of the rectangle. This demonstrates how to use the packet events to control application behaviors.
[Visual Basic]
Imports Microsoft.Ink
Public Class Form1
Inherits System.Windows.Forms.Form
Dim indexX, indexY As Integer
Dim rectInterest As Rectangle
Dim thickBorder As Boolean
'...
Public Sub New()
MyBase.New()
'This call is required by the Windows Form Designer.
InitializeComponent()
'Initialize the InkPicture control.
theInkPicture.InkEnabled = True
'Initialize the target rectangle
rectInterest = New Rectangle(40, 40, 200, 80)
thickBorder = False
'Save the X and Y data locations within the packet data.
GetXYIndexes(indexX, indexY)
'Add the event handler for in air packets
AddHandler theInkPicture.NewInAirPackets, AddressOf NewInAirPackets_Event
End Sub
'...
Private Sub GetXYIndexes(ByRef theXIndex As Integer, _
ByRef theYIndex As Integer)
' Get the indexes of the X and Y data within the raw
' packet data array.
Dim theGuids() As Guid = theInkPicture.DesiredPacketDescription
Dim i As Integer
For i = 0 To theGuids.Length - 1
If theGuids(i).Equals(PacketProperty.X) Then
theXIndex = i
End If
If theGuids(i).Equals(PacketProperty.Y) Then
theYIndex = i
End If
Next
End Sub
Private Sub NewInAirPackets_Event(ByVal sender As Object, _
ByVal e As InkCollectorNewInAirPacketsEventArgs)
'The event may return with data for multiple packets.
'To simplify things, we'll only look at the first.
If rectInterest.Contains( _
e.PacketData(indexX), e.PacketData(indexY)) Then
If thickBorder = False Then
thickBorder = True
Refresh()
End If
Else
If thickBorder = True Then
thickBorder = False
Refresh()
End If
End If
End Sub
Private Sub Form1_Paint(ByVal sender As Object, _
ByVal e As System.Windows.Forms.PaintEventArgs) _
Handles MyBase.Paint
Dim g As Graphics = e.Graphics
Dim thePen As New Pen(Color.Black, 2)
If thickBorder Then
thePen.Width = 5
End If
g.DrawRectangle(thePen, rectInterest)
End Sub
End Class
Platforms
Windows 98, Windows Server 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition
The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.
Version Information
.NET Framework
Supported in: 3.0
See Also
Reference
InkPicture Class
InkPicture Members
Microsoft.Ink Namespace
Cursor
InkCollectorNewInAirPacketsEventArgs
InkPicture.DesiredPacketDescription
InkPicture.NewPackets