EnableRadio not working for Android neither? Maybe on some versions of Android?

[rdehouss]

Good morning!

Thanks a lot already for this library ;)

I just tested the methods enableRadio and and despite the fact I see that it's unit tested and so, I understand that it must work somewhere, it throws an exception in my case.

I run the application directly on my phone, not an emulator, it fails in both debug and release build.

Best regards,

Raphaël

The version pubspec.lock

flutter_ble_lib:
    dependency: "direct main"
    description:
      name: flutter_ble_lib
      url: "https://pub.dartlang.org"
    source: hosted
    version: "2.2.3"

The code

if (Platform.isAndroid) {
  try {
    await bleManager.enableRadio();
  } catch (e) {
    print(e);
    await AppSettings.openBluetoothSettings();
  }
} else {
  await AppSettings.openAppSettings();
}

=> The error in debug build:

MissingPluginException (MissingPluginException(No implementation found for method enableRadio on channel flutter_ble_lib))

The error in release build:

I/flutter (15797): NoSuchMethodError: Class 'MissingPluginException' has no instance getter 'details'.
I/flutter (15797): Receiver: Instance of 'MissingPluginException'
I/flutter (15797): Tried calling: details

and

bleManager.observeBluetoothState().listen((btState) {
  print(btState);
});

=>

MissingPluginException (MissingPluginException(No implementation found for method getState on channel flutter_ble_lib))

while the following works correctly:

BluetoothState currentState = await bleManager.bluetoothState();
print(currentState);

Here is my flutter doctor -v

flutter doctor -v
[✓] Flutter (Channel stable, v1.12.13+hotfix.8, on Linux, locale en_US.UTF-8)
    • Flutter version 1.12.13+hotfix.8 at /opt/flutter
    • Framework revision 0b8abb4724 (7 weeks ago), 2020-02-11 11:44:36 -0800
    • Engine revision e1e6ced81d
    • Dart version 2.7.0

[✓] Android toolchain - develop for Android devices (Android SDK version 28.0.3)
    • Android SDK at /opt/android-sdk/
    • Android NDK location not configured (optional; useful for native profiling support)
    • Platform android-29, build-tools 28.0.3
    • ANDROID_HOME = /opt/android-sdk
    • ANDROID_SDK_ROOT = /opt/android-sdk
    • Java binary at: /opt/android-studio/jre/bin/java
    • Java version OpenJDK Runtime Environment (build 1.8.0_212-release-1586-b4-5784211)
    • All Android licenses accepted.

[✓] Android Studio (version 3.6)
    • Android Studio at /opt/android-studio
    • Flutter plugin version 44.0.2
    • Dart plugin version 192.7761
    • Java version OpenJDK Runtime Environment (build 1.8.0_212-release-1586-b4-5784211)

[✓] Connected device (1 available)
    • SM G935F • 988678454e47515938 • android-arm64 • Android 8.0.0 (API 26)

• No issues found!

[rdehouss]

Sorry, false alarm, it was because the code being sync, I was closing destroying the client too soon

The full faulty code

Future _scan(context) async {
    BleManager bleManager = BleManager();

    await bleManager.createClient();

    BluetoothState currentState = await bleManager.bluetoothState();
    print(currentState);

    if (currentState == BluetoothState.POWERED_OFF) {
      Scaffold.of(context).showSnackBar(SnackBar(
        content: Text(
          "Bluetooth is off, turn it on to be able to scan for Links",
        ),
        action: SnackBarAction(
          label: 'Turn on',
          onPressed: () async {
            if (Platform.isAndroid) {
              try {
                await bleManager.enableRadio();
              } catch (e) {
                print(e);
                await AppSettings.openBluetoothSettings();
              }
            } else {
              await AppSettings.openBluetoothSettings();
            }
          },
        ),
      ));
    }

    bleManager.observeBluetoothState().listen((btState) {
      print(btState);
    });

    return bleManager.destroyClient();
  }

The return bleManager.destroyClient(); was the issue :) Leaving the issue in case someone does the same than me ;)