I'm trying to learn about CoreBluetooth and External Accessories on iOS.
First, I tried to see a list of devices connect to my phone via Bluetooth via print(EAAccessoryManager.sharedAccessoryManager().connectedAccessories) ... despite having 3 devices connected (according to the Settings app), I'm given an empty array.
Next, I tried registering for connect / disconnect notifications:
import UIKit
import ExternalAccessory
class ViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
NSNotificationCenter.defaultCenter().addObserver(self,
selector: "somethingConnected:",
name: EAAccessoryDidConnectNotification,
object: nil)
NSNotificationCenter.defaultCenter().addObserver(self,
selector: "somethingDisconnected:",
name: EAAccessoryDidDisconnectNotification,
object: nil)
EAAccessoryManager.sharedAccessoryManager().registerForLocalNotifications()
}
func somethingConnected(name: EAAccessory) {
print("here")
}
func somethingDisconnected(name: EAAccessory) {
print("there")
}
}
... I receive nothing when I turn off/on (and thus disconnect/connect) a simple Bluetooth speaker I have.
I am seeing this issue (notifications not delivering until after the completion block of showBluetoothAccessoryPickerWithNameFilter() executes), but, generally, it seems like either:
A) Something with iOS isn't working correctly
B) I'm doing something wrong (the more likely of the two).
Do I need to have a special MFI certificate installed to see a list of connected Accessories? Why aren't notifications delivering?
Any recommendations / code examples are greatly appreciated.
Update
Most importantly: Still don't know why connectedAccessories doesn't work, so advice on this piece is greatly desired.
That said, re-reading the Apple Developer documentation, I don't believe that it's correct / possible to use NSNotificationCenter.defaultCenter().addObserver with these types of notifications.
Specifically, the documentation states that EA notifications will not be delivered until showBluetoothAccessoryPickerWithNameFilter() is called -- e.g. the EAAccessoryDidConnectNotification and EAAccessoryDidDisconnectNotification are meant to inform the app about what the User did with the picker dialogue. It doesn't seem that they are system-level notifications that can be picked up by NSNotificationCenter.
Please correct me if this is an incorrect reading.
