VS 2010 is out for some time now. Off course it brings some useful new features. Shure it needs more resources and does not run as quick as the 2008 version, that’s kind of what everyone would expect. However it carries quite a bad surprise for mobile developers….
Low and behold, support for smart device dev is gone!
MSDN is quite clear about it: “Visual Studio 2010 does not support mobile application development for versions of Windows Phone prior to Windows Phone OS 7.0.”
That’s quite a bummer. Hard to believe… why would I have to license a legacy IDE to develop software for state of the art mobile operating systems? Perhaps even license two IDEs?
With this in mind, it doesn’t surprise Android is gaining market shares…
Windows Mobile comes with an internal instance counter that will switch to an already existing window if a program is started more than just once.
Windows CE is lacking such a feature, but it is relatively painless to implement using P/Invoke and events.
public class SingleInstance : IDisposable
{
[DllImport( "Coredll.dll", SetLastError = true )]
static extern IntPtr CreateEvent( IntPtr ptrAlwaysZero, bool bManualReset, bool bInitialState, string lpName );
[DllImport( "Coredll.dll", SetLastError = true )]
static extern int CloseHandle( IntPtr handle );
private IntPtr Handle = IntPtr.Zero;
public bool IsSingleInstance { get { return this.Handle != IntPtr.Zero; } }
/// <summary>A running program is identified by an already existing event that is named the same as the executable path.</summary>
public SingleInstance() : this( Assembly.GetExecutingAssembly().GetModules()[ 0 ].FullyQualifiedName ) { }
/// <summary>Accepts a single string as a parameter.</summary>
public SingleInstance( string sEventName )
{
this.Handle = CreateEvent( IntPtr.Zero, true, false, sEventName );
if ( Marshal.GetLastWin32Error() != 0 )
Dispose();
}
public void Dispose()
{
if ( this.Handle != IntPtr.Zero )
CloseHandle( this.Handle );
this.Handle = IntPtr.Zero;
}
}You should make use of this class as early in the program as possible, e.g.
static class Program
{
[MTAThread]
static void Main()
{
using ( SingleInstance si = new SingleInstance() )
if ( si.IsSingleInstance )
Application.Run();
}
}Use of the above code is not restricted to Windows Mobile though. You could also use this snippet for regular Windows programs, just remember to replace the dllimport for Coredll.dll to kernel32.dll.