Minimal iOS BluetoothManager Example - iphone

Question

I've been constructing a minimal example for detecting nearby Bluetooth devices using the BluetoothManager private framework in iOS 5.0.
Using an answer found in this question: Finding generic Bluetooth devices within reach
Here's my viewDidLoad method to register for the BluetoothAvailabilityChangedNotification. I also register for the BluetoothDeviceDiscoveredNotification as well.
[[NSNotificationCenter defaultCenter]
addObserver:self
selector:#selector(bluetoothAvailabilityChanged:)
name:#"BluetoothAvailabilityChangedNotification"
object:nil];
btCont = [BluetoothManager sharedInstance];
[[NSNotificationCenter defaultCenter]
addObserver:self
selector:#selector(deviceDiscovered:)
name:#"BluetoothDeviceDiscoveredNotification"
object:nil];
When I get the Bluetooth availability changed notification, I set the device scanning enabled, as outlined in one of the answers in the aforementioned link.
- (void)bluetoothAvailabilityChanged:(NSNotification *)notification
{
NSLog(#"BT State: %d", [btCont enabled]);
[btCont setDeviceScanningEnabled:YES];
}
For completeness, here's the deviceDiscovered notification method.
- (void)deviceDiscovered:(NSNotification *) notification
{
NSLog(#"Discovered one!");
}
The logs produced by running the test application are as follows:
BTM: attaching to BTServer
BTM: posting notification BluetoothAvailabilityChangedNotification
BT State: 1
BTM: setting device scanning enabled
Unfortunately, the phone isn't picking up any Bluetooth devices at all, even though I know there are proximate discoverable devices (verified using an Android device).
Some things I have tried already:
Calling [btCont setPowered: YES]; and registering for the associated power state change notification, executing setDeviceScanningEnabled:YES in the callback
Calling [btCont resetDeviceScanning] prior to the setDeviceScanningEnabled call
Calling the scanForConnectableDevices:(unsigned int)arg1; method, guessing that arg1 may be some kind of timeout value. I've tried a variety of values with no success.
Any thoughts would be much appreciated.
Thanks!

Answer 1

As far as I know, the bluetooth manager gets the list after OS has filtered the results.
You will only get the nearby headset devices and not all generic devices.
you have to use scanForServices:
// start scan
[btManager setDeviceScanningEnabled:YES];
[btManager scanForServices:0xFFFFFFFF];