无法在android上检测usb连接
我有一个安卓5.1.1设备,一根OTG电缆和一个ACS读卡器。我想检测读卡器何时通过OTG电缆插入。我可以检测到无法在android上检测usb连接,android,usb-otg,Android,Usb Otg,我有一个安卓5.1.1设备,一根OTG电缆和一个ACS读卡器。我想检测读卡器何时通过OTG电缆插入。我可以检测到分离,但是附加不成功 以下是我所拥有的: 清单文件: <uses-feature android:name="android.hardware.usb.host" /> <application android:allowBackup="true" android:icon="@mipmap/ic_launcher" android:labe
分离
,但是附加
不成功
以下是我所拥有的:
清单文件:
<uses-feature android:name="android.hardware.usb.host" />
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:supportsRtl="true"
android:theme="@style/AppTheme">
<activity
android:name=".MainActivity"
android:label="@string/app_name"
android:theme="@style/AppTheme.NoActionBar">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<action android:name="android.hardware.usb.action.USB_DEVICE_ATTACHED" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
<meta-data
android:name="android.hardware.usb.action.USB_DEVICE_ATTACHED"
android:resource="@xml/device_filter" />
</activity>
</application>
我还没有请求许可,我会在检测到时询问。无论发生什么,我都看不到预期的日志
我检查了鼠标和U盘;也无法检测到它们。
Android设备支持OTG和读卡器;与其他应用程序一起检查。我猜他们会定时检查是否连接了USB设备。尝试通过可编程方式创建意图过滤器: 1) 除去 3) 在中使用权限
UsbManager.ACTION_USB_DEVICE_ATTACHED.equals(action)
案例。将很快重试,但问题似乎是android版本5.1.1它是设备或android版本问题。解决方案的问题是,接收器将仅在应用程序启动时注册。这意味着,如果你先启动,android系统只会将广播传送给应用程序。但它不会在后台监听。@Radon8472同意,但它可以在
服务
中通过启动完成
实现。这只是一种方法,而不是最终的解决方案。
private static final String TAG = MainActivity.class.getSimpleName();
private static final String ACTION_USB_PERMISSION = "com.guness.deleteme.USB_PERMISSION";
private final BroadcastReceiver mUsbReceiver = new BroadcastReceiver() {
public void onReceive(Context context, Intent intent) {
String action = intent.getAction();
if (ACTION_USB_PERMISSION.equals(action)) {
synchronized (this) {
UsbDevice device = intent.getParcelableExtra(UsbManager.EXTRA_DEVICE);
if (intent.getBooleanExtra(UsbManager.EXTRA_PERMISSION_GRANTED, false)) {
if (device != null) {
//call method to set up device communication
Log.e(TAG, "permission granted " + device);
}
} else {
Log.e(TAG, "permission denied for device " + device);
}
}
}
}
};
private PendingIntent mPermissionIntent;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Log.e(TAG, "onCreate");
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
mPermissionIntent = PendingIntent.getBroadcast(this, 0, new Intent(ACTION_USB_PERMISSION), 0);
IntentFilter filter = new IntentFilter(ACTION_USB_PERMISSION);
registerReceiver(mUsbReceiver, filter);
}
@Override
protected void onResume() {
super.onResume();
Log.e(TAG, "onResume");
}
@Override
protected void onNewIntent(Intent intent) {
super.onNewIntent(intent);
Log.e(TAG, "onNewIntent");
}
<action android:name="android.hardware.usb.action.USB_DEVICE_ATTACHED" />
<meta-data
android:name="android.hardware.usb.action.USB_DEVICE_ATTACHED"
android:resource="@xml/device_filter" />
private static final String TAG = MainActivity.class.getSimpleName();
private final BroadcastReceiver mUsbReceiver = new BroadcastReceiver() {
public void onReceive(Context context, Intent intent) {
String action = intent.getAction();
if (UsbManager.ACTION_USB_DEVICE_ATTACHED.equals(action)) {
Log.d(TAG, "USB device attached");
} else if (UsbManager.ACTION_USB_DEVICE_DETACHED.equals(action)) {
Log.d(TAG, "USB device detached");
}
}
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Log.e(TAG, "onCreate");
setContentView(R.layout.activity_main);
IntentFilter filter = new IntentFilter();
filter.addAction(UsbManager.ACTION_USB_DEVICE_ATTACHED);
filter.addAction(UsbManager.ACTION_USB_DEVICE_DETACHED);
registerReceiver(mUsbReceiver, filter);
}
UsbManager.ACTION_USB_DEVICE_ATTACHED.equals(action)