Every time on scanning bluetooth devices gives CBCentralManagerStateUnknown? - core-bluetooth

Question

First time I am using coreBluetooth.
Here is my implementation is there any thing wrong in it.
#synthesize CM,activePeripheral;
- (id)init
{
if ((self = [super init]))
{
CM = [[CBCentralManager alloc]initWithDelegate:self queue:dispatch_get_main_queue()];
}
return self;
}
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
}
- (int) scanForPeripherals
{
if (self.CM.state != CBCentralManagerStatePoweredOn)
{
NSLog(#"CoreBluetooth is %s",[self centralManagerStateToString:self.CM.state]);
return -1;
}
[self.CM scanForPeripheralsWithServices:[NSArray arrayWithObject:[CBUUID UUIDWithString:#"180D"]] options:#{CBCentralManagerScanOptionAllowDuplicatesKey: #YES}];
return 0;
}
- (const char *) centralManagerStateToString: (int)state
{
switch(state)
{
case CBCentralManagerStateUnknown:
return "State unknown (CBCentralManagerStateUnknown)";
case CBCentralManagerStateResetting:
return "State resetting (CBCentralManagerStateUnknown)";
case CBCentralManagerStateUnsupported:
return "State BLE unsupported (CBCentralManagerStateResetting)";
case CBCentralManagerStateUnauthorized:
return "State unauthorized (CBCentralManagerStateUnauthorized)";
case CBCentralManagerStatePoweredOff:
return "State BLE powered off (CBCentralManagerStatePoweredOff)";
case CBCentralManagerStatePoweredOn:
return "State powered up and ready (CBCentralManagerStatePoweredOn)";
default:
return "State unknown";
}
return "Unknown state";
}
- (void) connectPeripheral:(CBPeripheral *)peripheral {
printf("Connecting to peripheral with UUID : %s\r\n",[self UUIDToString:peripheral.UUID]);
self.activePeripheral = peripheral;
self.activePeripheral.delegate = self;
[self.CM connectPeripheral:self.activePeripheral options:[NSDictionary dictionaryWithObject:[NSNumber numberWithBool:YES] forKey:CBConnectPeripheralOptionNotifyOnDisconnectionKey]];
}
-(const char *) UUIDToString:(CFUUIDRef)UUID
{
if (!UUID)
return "NULL";
CFStringRef s = CFUUIDCreateString(NULL, UUID);
return CFStringGetCStringPtr(s, 0);
}
#pragma mark -Central manager delegate method
- (void)centralManagerDidUpdateState:(CBCentralManager *)central
{
NSLog(#"hits it");
if (central.state != CBCentralManagerStatePoweredOn) {
return;
}
isOn=YES;
}
- (void)centralManager:(CBCentralManager *)central didDiscoverPeripheral:(CBPeripheral *)peripheral advertisementData:(NSDictionary *)advertisementData RSSI:(NSNumber *)RSSI
{
NSLog(#"Received periferal :%#",peripheral);
NSLog(#"Ad data :%#",advertisementData);
[MBProgressHUD hideHUDForView:self.view animated:YES];
}
- (void)centralManager:(CBCentralManager *)central didConnectPeripheral:(CBPeripheral *)peripheral
{
NSLog(#"Connected peripheral %#",peripheral);
}
- (void)centralManager:(CBCentralManager *)central didFailToConnectPeripheral:(CBPeripheral *)peripheral error:(NSError *)error
{
NSLog(#"Error occured :%#",[error localizedDescription]);
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
- (IBAction)scanDevices:(id)sender {
if (isOn) {
[MBProgressHUD showHUDAddedTo:self.view animated:YES];
[self scanForPeripherals];
}
}
Every time it gives log
CoreBluetooth is State unknown (CBCentralManagerStateUnknown)
update to question
After suggestion given by #Michael Dautermann , I come to know that my centralManagerDidUpdateState delegate method is not hitting.I dunno why this is happening.If anybody finds the reason please notify me.
Thanks you.

Answer 1

CoreBluetooth is simply in the process of starting up.
You need this delegate method to hit first:
- (void) centralManagerDidUpdateState: (CBCentralManager *) central;
And once it does, then you can start scanning for peripherals.

Answer 2

After few days, I checked out the initialization of CentralManager and I come to know that init method on firstViewController never called.I checked out by printing log in init method.
- (id)init
{
NSLog(#"hello init");
if ((self = [super init]))
{
CM = [[CBCentralManager alloc]initWithDelegate:self queue:dispatch_get_main_queue()];
}
return self;
}
- (void)viewDidLoad
{ CM = [[CBCentralManager alloc]initWithDelegate:self queue:dispatch_get_main_queue()];
isOn=NO;
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
}
So , I initialize the central manager in viewDidLoad and now it is initialized and centralManagerDidUpdateState finally called.Now printing CBCentralManagerStateUnsupported and that's not the issue because iPhone 4 doesn't support it.Thanks to michael help me a lot.

Answer 3

Where do you call scanDevices? I think you're calling it too early. You should call it inside centralManagerDidUpdateState.
- (void)centralManagerDidUpdateState:(CBCentralManager *)central
{
NSLog(#"hits it");
if (central.state != CBCentralManagerStatePoweredOn) {
[self scanDevices]:
}
isOn=YES;
}