java - UsbDevice requestPermission 被拒绝而不显示请求对话框提示

问题描述

我正在尝试使用连接到我的 android 设备的 USB 相机设备。所以最初我已经获得了通过UsbManager.getDeviceList()方法连接的 USB 设备的详细信息。然后，我遍历每个设备，并在尚未授予权限的情况下请求权限。

在请求许可之前，我已经注册了一个全局BroadCastReceiver来监听请求许可的响应。

这是 MainActivity.java：

public class MainActivity extends AppCompatActivity {

    private UsbManager usbManager_;
    private static final String ACTION_USB_PERMISSION = "com.android.example.USB_PERMISSION";
    public PendingIntent permissionIntent;
    private static String TAG = "testing";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

//        SurroundView surroundView = new SurroundView(this);
//        setContentView(surroundView);

        usbManager_ = (UsbManager) getSystemService(USB_SERVICE);
        permissionIntent = PendingIntent.getBroadcast(this, 0, new Intent(ACTION_USB_PERMISSION), 0);

        requestUsbPermissions();
    }

    private final BroadcastReceiver usbReceiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            String action = intent.getAction();
            Log.i(TAG, "received intent by broadcast " + intent.getAction());
            if (ACTION_USB_PERMISSION.equals(action)) {
                synchronized (this) {
                    UsbDevice device = (UsbDevice) intent.getParcelableExtra(UsbManager.EXTRA_DEVICE);
                    if (intent.getBooleanExtra(UsbManager.EXTRA_PERMISSION_GRANTED, false)) {
                        if (device != null) {
                            Log.i(TAG, "got the permission");
                        }
                    } else {
                        Log.d(TAG, "permission denied for device " + device);
                    }
                }
            }
        }
    };

    public void requestUsbPermissions(){
        HashMap<String, UsbDevice> deviceList = usbManager_.getDeviceList();
        IntentFilter filter = new IntentFilter(ACTION_USB_PERMISSION);
        this.registerReceiver(usbReceiver, filter);
        Log.i(TAG, "registered broadcast receiver!");
        Iterator<UsbDevice> deviceIterator = deviceList.values().iterator();
        while (deviceIterator.hasNext()) {
            UsbDevice device = deviceIterator.next();
            Log.i(TAG,
                    "Camera: device Id " + device.getDeviceId() + " device mName : " + device.getDeviceName());
            if (!usbManager_.hasPermission(device)) {
                Log.i(TAG, "requesting permission");
                usbManager_.requestPermission(device, permissionIntent);
            }
        }
    }
}

因此，当我运行该应用程序时，它会检测到一个连接的 USB 设备并请求相同的权限。但是要求用户输入的对话框永远不会出现。相反，当意图被接收时，BroadCastReceiver的值intent.getBooleanExtra(UsbManager.EXTRA_PERMISSION_GRANTED, false)将始终为 false，这意味着权限已被拒绝。谁能向我解释为什么对话框没有出现在首位以及为什么权限被自动拒绝。

这是我的 AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.vision_sdk_testing">

    <uses-feature android:name="android.hardware.usb.host" android:required="true"/>
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>
    <uses-permission android:name="android.permission.INTERNET" />
    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

以下是输出日志：

2020-05-01 17:56:05.282 30769-30769/com.example.vision_sdk_testing I/testing: registered broadcast receiver!
2020-05-01 17:56:05.283 30769-30769/com.example.vision_sdk_testing I/testing: Camera: device Id 1003 device mName : /dev/bus/usb/001/003
2020-05-01 17:56:05.283 30769-30769/com.example.vision_sdk_testing I/testing: requesting permission
2020-05-01 17:56:05.301 30769-30769/com.example.vision_sdk_testing I/testing: received intent by broadcast com.android.example.USB_PERMISSION
2020-05-01 17:56:05.302 30769-30769/com.example.vision_sdk_testing D/testing: permission denied for device UsbDevice[mName=/dev/bus/usb/001/003,mVendorId=1443,mProductId=38192,mClass=239,mSubclass=2,mProtocol=1,mManufacturerName=Sonix Technology Co., Ltd.,mProductName=USB 2.0 Camera,mVersion=1.00,mSerialNumberReader=android.hardware.usb.IUsbSerialReader$Stub$Proxy@d41ebfa,mConfigurations=[
    UsbConfiguration[mId=1,mName=null,mAttributes=128,mMaxPower=128,mInterfaces=[
    UsbInterface[mId=0,mAlternateSetting=0,mName=HD USB Camera,mClass=14,mSubclass=1,mProtocol=0,mEndpoints=[]]
    UsbConfiguration[mId=3,mName=null,mAttributes=3,mMaxPower=88,mInterfaces=[]]

任何帮助表示赞赏。谢谢！

标签： javaandroidusbandroid-permissionsusbmanager

java - UsbDevice requestPermission 被拒绝而不显示请求对话框提示

问题描述

解决方案

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