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扫描无法在 Android Things DP3 上运行的蓝牙设备。任何想法/解决方法？未采取行动 BluetoothDevice.ACTION_FOUND。

由于 Android 6.0 中的更改，我添加了 ACCESS_FINE_LOCATION 和 ACCESS_COARSE_LOCATION 权限，但仍然无法正常工作。 https://developer.android.com/about/versions/marshmallow/android-6.0-changes.html

还有 android.permission.BLUETOOTH_ADMIN、android.permission.BLUETOOTH

我已经检查过，Android >=6.0 上的 ACCESS_FINE_LOCATION 或 ACCESS_COARSE_LOCATION 需要运行时权限，但由于 Android Things 限制它会给出错误。

private void checkPermission() {

    List<String> permissionsList = new ArrayList<String>();
    List<String> permissionsNeeded = new ArrayList<String>();

    // app
    permissionsList.add(Manifest.permission.ACCESS_FINE_LOCATION);
    permissionsList.add(Manifest.permission.ACCESS_COARSE_LOCATION);
    permissionsList.add(Manifest.permission.ACCESS_WIFI_STATE);
    permissionsList.add(Manifest.permission.SET_TIME_ZONE);
    // AndroidThingsLib
    permissionsList.add(Manifest.permission.BLUETOOTH_ADMIN);
    permissionsList.add(Manifest.permission.BLUETOOTH);
    permissionsList.add(Manifest.permission.CHANGE_WIFI_STATE);
    permissionsList.add(Manifest.permission.INTERNET);
    permissionsList.add(Manifest.permission.ACCESS_NETWORK_STATE);

    for (int i = 0; i < permissionsList.size(); i++){
        if (checkSelfPermission(permissionsList.get(i)) == PackageManager.PERMISSION_GRANTED) {
            permissionsNeeded.add(permissionsList.get(i));
            updateDataLogs(SourceEnum.System, "GRANTED: " + permissionsList.get(i));
        } else {
            permissionsNeeded.add(permissionsList.get(i));
            updateDataLogs(SourceEnum.Error, "NOT GRANTED: " + permissionsList.get(i));
        }
    }

    if (permissionsList.size()>0){
        requestPermissions(permissionsNeeded.toArray(new String[permissionsNeeded.size()]),5678);
    }
}

@Override
public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
    if (requestCode == 5678){
        for (int i = 0; i < permissions.length; i++){
            updateDataLogs(SourceEnum.Error, permissions[i] + " result " + grantResults[i]);
        }
    }
}
private void enableBluetoothScan() {
    updateDataLogs(SourceEnum.System, "enableBluetoothScan");

    IntentFilter filter = new IntentFilter();
    filter.addAction(BluetoothDevice.ACTION_FOUND);
    filter.addAction(BluetoothAdapter.ACTION_DISCOVERY_STARTED);
    filter.addAction(BluetoothAdapter.ACTION_DISCOVERY_FINISHED);
    registerReceiver(mReceiver, filter);

    BluetoothAdapter bluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
    if (bluetoothAdapter.isEnabled()){
        bluetoothAdapter.startDiscovery();
    } else {
        updateDataLogs(SourceEnum.Error, "Bluetooth Adapter not enabled");
    }
}

private final BroadcastReceiver mReceiver = new BroadcastReceiver() {
    public void onReceive(Context context, Intent intent) {
        String action = intent.getAction();
        if (BluetoothAdapter.ACTION_DISCOVERY_STARTED.equals(action)) {
            updateDataLogs(SourceEnum.System, "DISCOVERY STARTED");
        } else if (BluetoothAdapter.ACTION_DISCOVERY_FINISHED.equals(action)) {
            updateDataLogs(SourceEnum.System, "DISCOVERY FINISHED");
        } else if (BluetoothDevice.ACTION_FOUND.equals(action)) {
            BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
            if (device.getBondState() != BluetoothDevice.BOND_BONDED)    {
                updateDataLogs(SourceEnum.System, "NEW DEVICE " + device.getName());
            }
        }
    }
};
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2 回答 2

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如平台概述中所述，Android Things 不支持运行时权限授予，因为设备可能没有交互式显示屏来显示对话框。相反，对于清单中请求的所有权限，Android Things 会使用安装时权限模型。这意味着不需要调用类似requestPermissions()的方法，也不会帮助您。

关于当前预览期间遇到的问题，以下摘自发行说明：

应用程序请求的危险权限在下次设备重启之前不会被授予。这包括新应用安装和现有应用中的新元素。

目前，当您的应用请求危险权限（如位置权限）时，您需要在安装后（一次性）重新启动设备，以便在启动期间授予这些权限。

于 2017-04-24T04:18:42.087 回答
0

感谢您的解释，您已经做了什么，我能够克服这个问题。因为您尚未将问题标记为已解决：

build.gradle （应用程序；感谢1和2）：

apply plugin: 'com.android.application'

android {
    compileSdkVersion 24
    <!-- update this to your version of the Android SDK Tools -->
    buildToolsVersion "25.0.3"
    defaultConfig {
        minSdkVersion 24
    }
}

dependencies {
    <!-- update this to your version of Android Things -->
    provided 'com.google.android.things:androidthings:0.4-devpreview'
}

AndroidManifest.xml （感谢1和2）：

<manifest xmlns:android="http://schemas.android.com/apk/res/android" package=" . . . ">

    <!-- required for getState in startDiscovery -->
    <uses-permission android:name="android.permission.BLUETOOTH"/>
    <!-- required for startDiscovery -->
    <uses-permission android:name="android.permission.BLUETOOTH_ADMIN"/>
    <!-- required for the IntentFilter ACTION_FOUND -->
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>

    <!-- change to your label -->
    <application android:label="Intel Edison">
        <uses-library android:name="com.google.android.things"/>

        <!-- change to the name of your Main Activity -->
        <activity android:name=".HomeActivity">
            <!-- Launch activity as default from Android Studio -->
            <intent-filter>
                <action android:name="android.intent.action.MAIN"/>
                <category android:name="android.intent.category.LAUNCHER"/>
            </intent-filter>

            <!-- Launch activity automatically on boot -->
            <intent-filter>
                <action android:name="android.intent.action.MAIN"/>
                <category android:name="android.intent.category.IOT_LAUNCHER"/>
                <category android:name="android.intent.category.DEFAULT"/>
            </intent-filter>
        </activity>
    </application>
</manifest>

HomeActivity.java：

IntentFilter filter = new IntentFilter();
filter.addAction(BluetoothAdapter.ACTION_STATE_CHANGED);
filter.addAction(BluetoothAdapter.ACTION_DISCOVERY_STARTED);
filter.addAction(BluetoothAdapter.ACTION_DISCOVERY_FINISHED);
filter.addAction(BluetoothDevice.ACTION_FOUND);
filter.addAction(BluetoothDevice.ACTION_NAME_CHANGED);
registerReceiver(mReceiverBT, filter);

BluetoothAdapter mBtAdapter = BluetoothAdapter.getDefaultAdapter();
boolean started = mBtAdapter.startDiscovery();
if (false == started) {
    <!-- in that case, catch BluetoothAdapter.STATE_ON in the receiver and start the Bluetooth Discovery then -->
    mBtAdapter.enable();
}

使用此代码，我的应用程序在启动英特尔爱迪生板后立即启动，并且能够发现附近的蓝牙设备。笔记：

  • 在这个板上，Android Things 需要 69 秒（开发者预览版 4）或 82 秒（开发者预览版 3）来启动我的应用程序。
  • 在 logcat 中，我看到“未授予 android.permission.ACCESS_COARSE_LOCATION 打包权限……因为它之前没有安装”。我找不到解决办法。在问题 62514750中报告。
  • 实际上，您可能根本不需要任何“危险”许可——例如，我对 ACTION_FOUND 什么都不做——因为在我的场景中总是在这里触发 ACTION_NANE_CHANGED；在问题 62524160中报告。
于 2017-06-12T09:38:28.760 回答