[mono-android] FW: Bluetooth Connect NullPointerException

[Steve Sharrock]

OK - I'm an idiot. I rebooted the Galaxy Tab 2 and re-paired the scanner and
now all works fine with either the secure or insecure socket.

Thanks for the reply. 


Steve Sharrock
Architecture/Design/Programming
www.sharkcode.com

-----Original Message-----
From: Jonathan Pryor [mailto:jonp at xamarin.com]
Sent: Tuesday, October 16, 2012 6:54 AM
To: steve at sharkcode.com; Discussions related to Mono for Android
Subject: Re: [mono-android] Bluetooth Connect NullPointerException

On Oct 16, 2012, at 9:38 AM, Steve Sharrock <steve at sharkcode.com> wrote:
> I've been testing with different Barcode Scanners and RFID Readers and
most of them work fine, except one scanner paired with a Galaxy Tab 2. A
Google search revealed that the Galaxy Tab 2 does have some Bluetooth
issues, and the recommended work-around is to use an Insecure Socket.
>  
> IntPtr createInsecureRfcommSocket = JNIEnv.GetMethodID( 
> device.Class.Handle, "createInsecureRfcommSocket", 
> "(I)Landroid/bluetooth/BluetoothSocket;" ); IntPtr socketHandle = 
> JNIEnv.CallObjectMethod( device.Handle, createInsecureRfcommSocket, 
> new JValue( 1 ) );

Is socketHandle IntPtr.Zero?

> s = Java.Lang.Object.GetObject<BluetoothSocket>( socketHandle, 
> JniHandleOwnership.TransferLocalRef ); This doesn't work for me either and
throws the NullPointerException when I try Socket.Connect(). Is my syntax
correct in the Insecure code snippet?

What's the full stack trace that you get?

Java.Lang.Object.GetObject<T>() should return null if the handle is
IntPtr.Zero.

 - Jon