Question

参考本指南：http://developer.android.com/guide/topics/connectivity/bluetooth-le.html我尝试运行BluetoothAdapter.StartLeScan(BluetoothAdapter.ILeScanCallback)方法。这是假的，我不知道为什么。

在我的清单中，我为BLUETOOTH和BLUETOOTH_ADMIN启用了权限。我通过运行Activity.ApplicationContext.CheckCallingOrSelfPermission("android.permission.BLUETOOTH")和Activity.ApplicationContext.CheckCallingOrSelfPermission("android.permission.BLUETOOTH_ADMIN")确认了这一点。这些都返回Android.Content.PM.Permission.Granted但BluetoothAdapter.StartLeScan(BluetoothAdapter.ILeScanCallback)返回false。

可能导致此返回false的原因是什么？

BluetoothAdapter adapter = BluetoothAdapter.DefaultAdapter;

// activity set in class constructor

var res = activity.ApplicationContext.CheckCallingOrSelfPermission("android.permission.BLUETOOTH");
// returns Android.Content.PM.Permission.Granted
var res2 = activity.ApplicationContext.CheckCallingOrSelfPermission("android.permission.BLUETOOTH_ADMIN");
// returns Android.Content.PM.Permission.Granted

Handler handler = new Handler();

handler.PostDelayed(delegate
{
    adapter.StopLeScan(this);
}, 4000);

var boolerson = adapter.StartLeScan(this); // returns false... why?

Answer 1

问题似乎是我在我创建的库中调用了BlutoothAdapter.StartLeScan(BluetoothAdapter.ILeScanCallback)。当我直接从我的应用程序代码中调用它时，它返回true。这似乎不应该，但确实如此。

Answer 2

<uses-permission android:name="android.permission.BLUETOOTH" />
    <uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
    <uses-permission android:name="android.permission.BLUETOOTH_PRIVILEGED" />
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />

这些权限是必要的。

Xamarin Android BLE - BluetoothAdapter.StartLeScan返回false

2 个答案: