我知道这有点晚了，但仍然...
我有同样的问题，我想我已经设法解决了。Android 内部使用了一项服务，可以管理 USB 设备和配件。此服务对第三方开发人员是隐藏的，并且没有记录在案。如果您检查 UsbPermissionActivity 的源代码，您将能够弄清楚该服务是如何被调用的。为了调用服务 IUsbManager 接口和 ServiceManager 类被使用。这些都是隐藏的，所以你不能直接使用它们。但是您可以做的是在相应的名称空间（包）中创建具有完全相同名称的存根。然后您将能够编译该代码，而运行时环境将使用真实的东西。
唯一的要求是您的应用程序必须是系统应用程序- 即它必须位于 /system/app/ 目录中。由于您的设备已植根，这应该不是问题。
所以你必须在你的项目中添加一个包：“ android.hardware.usb ”并在其中放入一个名为“ IUsbManager.java ”的文件，内容如下：
package android.hardware.usb;
public interface IUsbManager extends android.os.IInterface
{
/** Local-side IPC implementation stub class. */
public static abstract class Stub extends android.os.Binder implements android.hardware.usb.IUsbManager
{
/** Construct the stub at attach it to the interface. */
public Stub()
{
throw new RuntimeException( "Stub!" );
}
/**
* Cast an IBinder object into an android.hardware.usb.IUsbManager interface,
* generating a proxy if needed.
*/
public static android.hardware.usb.IUsbManager asInterface( android.os.IBinder obj )
{
throw new RuntimeException( "Stub!" );
}
public android.os.IBinder asBinder()
{
throw new RuntimeException( "Stub!" );
}
public boolean onTransact( int code, android.os.Parcel data, android.os.Parcel reply, int flags ) throws android.os.RemoteException
{
throw new RuntimeException( "Stub!" );
}
static final int TRANSACTION_getDeviceList = (android.os.IBinder.FIRST_CALL_TRANSACTION + 0);
static final int TRANSACTION_openDevice = (android.os.IBinder.FIRST_CALL_TRANSACTION + 1);
static final int TRANSACTION_getCurrentAccessory = (android.os.IBinder.FIRST_CALL_TRANSACTION + 2);
static final int TRANSACTION_openAccessory = (android.os.IBinder.FIRST_CALL_TRANSACTION + 3);
static final int TRANSACTION_setDevicePackage = (android.os.IBinder.FIRST_CALL_TRANSACTION + 4);
static final int TRANSACTION_setAccessoryPackage = (android.os.IBinder.FIRST_CALL_TRANSACTION + 5);
static final int TRANSACTION_hasDevicePermission = (android.os.IBinder.FIRST_CALL_TRANSACTION + 6);
static final int TRANSACTION_hasAccessoryPermission = (android.os.IBinder.FIRST_CALL_TRANSACTION + 7);
static final int TRANSACTION_requestDevicePermission = (android.os.IBinder.FIRST_CALL_TRANSACTION + 8);
static final int TRANSACTION_requestAccessoryPermission = (android.os.IBinder.FIRST_CALL_TRANSACTION + 9);
static final int TRANSACTION_grantDevicePermission = (android.os.IBinder.FIRST_CALL_TRANSACTION + 10);
static final int TRANSACTION_grantAccessoryPermission = (android.os.IBinder.FIRST_CALL_TRANSACTION + 11);
static final int TRANSACTION_hasDefaults = (android.os.IBinder.FIRST_CALL_TRANSACTION + 12);
static final int TRANSACTION_clearDefaults = (android.os.IBinder.FIRST_CALL_TRANSACTION + 13);
static final int TRANSACTION_setCurrentFunction = (android.os.IBinder.FIRST_CALL_TRANSACTION + 14);
static final int TRANSACTION_setMassStorageBackingFile = (android.os.IBinder.FIRST_CALL_TRANSACTION + 15);
}
/* Returns a list of all currently attached USB devices */
public void getDeviceList( android.os.Bundle devices ) throws android.os.RemoteException;
/* Returns a file descriptor for communicating with the USB device.
* The native fd can be passed to usb_device_new() in libusbhost.
*/
public android.os.ParcelFileDescriptor openDevice( java.lang.String deviceName ) throws android.os.RemoteException;
/* Returns the currently attached USB accessory */
public android.hardware.usb.UsbAccessory getCurrentAccessory() throws android.os.RemoteException;
/* Returns a file descriptor for communicating with the USB accessory.
* This file descriptor can be used with standard Java file operations.
*/
public android.os.ParcelFileDescriptor openAccessory( android.hardware.usb.UsbAccessory accessory ) throws android.os.RemoteException;
/* Sets the default package for a USB device
* (or clears it if the package name is null)
*/
public void setDevicePackage( android.hardware.usb.UsbDevice device, java.lang.String packageName ) throws android.os.RemoteException;
/* Sets the default package for a USB accessory
* (or clears it if the package name is null)
*/
public void setAccessoryPackage( android.hardware.usb.UsbAccessory accessory, java.lang.String packageName ) throws android.os.RemoteException;
/* Returns true if the caller has permission to access the device. */
public boolean hasDevicePermission(android.hardware.usb.UsbDevice device) throws android.os.RemoteException;
/* Returns true if the caller has permission to access the accessory. */
public boolean hasAccessoryPermission( android.hardware.usb.UsbAccessory accessory ) throws android.os.RemoteException;
/* Requests permission for the given package to access the device.
* Will display a system dialog to query the user if permission
* had not already been given.
*/
public void requestDevicePermission( android.hardware.usb.UsbDevice device, java.lang.String packageName, android.app.PendingIntent pi ) throws android.os.RemoteException;
/* Requests permission for the given package to access the accessory.
* Will display a system dialog to query the user if permission
* had not already been given. Result is returned via pi.
*/
public void requestAccessoryPermission( android.hardware.usb.UsbAccessory accessory, java.lang.String packageName, android.app.PendingIntent pi ) throws android.os.RemoteException;
/* Grants permission for the given UID to access the device */
public void grantDevicePermission( android.hardware.usb.UsbDevice device, int uid ) throws android.os.RemoteException;
/* Grants permission for the given UID to access the accessory */
public void grantAccessoryPermission( android.hardware.usb.UsbAccessory accessory, int uid ) throws android.os.RemoteException;
/* Returns true if the USB manager has default preferences or permissions for the package */
public boolean hasDefaults( java.lang.String packageName ) throws android.os.RemoteException;
/* Clears default preferences and permissions for the package */
public void clearDefaults( java.lang.String packageName ) throws android.os.RemoteException;
/* Sets the current USB function. */
public void setCurrentFunction( java.lang.String function, boolean makeDefault ) throws android.os.RemoteException;
/* Sets the file path for USB mass storage backing file. */
public void setMassStorageBackingFile( java.lang.String path ) throws android.os.RemoteException;
}
然后是另一个包：“ android.os ”和“ ServiceManager.java ”：
package android.os;
import java.util.Map;
public final class ServiceManager
{
public static IBinder getService( String name )
{
throw new RuntimeException( "Stub!" );
}
/**
* Place a new @a service called @a name into the service
* manager.
*
* @param name the name of the new service
* @param service the service object
*/
public static void addService( String name, IBinder service )
{
throw new RuntimeException( "Stub!" );
}
/**
* Retrieve an existing service called @a name from the
* service manager. Non-blocking.
*/
public static IBinder checkService( String name )
{
throw new RuntimeException( "Stub!" );
}
public static String[] listServices() throws RemoteException
{
throw new RuntimeException( "Stub!" );
}
/**
* This is only intended to be called when the process is first being brought
* up and bound by the activity manager. There is only one thread in the process
* at that time, so no locking is done.
*
* @param cache the cache of service references
* @hide
*/
public static void initServiceCache( Map<String, IBinder> cache )
{
throw new RuntimeException( "Stub!" );
}
}
请注意，这些类的接口可能会根据 Android 的版本而变化。在我的情况下，版本是4.0.3。因此，如果您有另一个版本的 Android 并且此代码不起作用，您将必须检查您的特定操作系统版本的源代码。
以下是使用该服务向所有 FTDI 设备授予权限的示例：
import java.util.HashMap;
import java.util.Iterator;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.pm.ApplicationInfo;
import android.content.pm.PackageManager;
import android.hardware.usb.IUsbManager;
import android.hardware.usb.UsbDevice;
import android.hardware.usb.UsbManager;
import android.os.IBinder;
import android.os.ServiceManager;
public class LaunchReceiver extends BroadcastReceiver
{
public void onReceive( Context context, Intent intent )
{
String action = intent.getAction();
if( action != null && action.equals( Intent.ACTION_BOOT_COMPLETED ) )
{
try
{
PackageManager pm = context.getPackageManager();
ApplicationInfo ai = pm.getApplicationInfo( YOUR_APP_PACKAGE_NAMESPACE, 0 );
if( ai != null )
{
UsbManager manager = (UsbManager) context.getSystemService( Context.USB_SERVICE );
IBinder b = ServiceManager.getService( Context.USB_SERVICE );
IUsbManager service = IUsbManager.Stub.asInterface( b );
HashMap<String, UsbDevice> deviceList = manager.getDeviceList();
Iterator<UsbDevice> deviceIterator = deviceList.values().iterator();
while( deviceIterator.hasNext() )
{
UsbDevice device = deviceIterator.next();
if( device.getVendorId() == 0x0403 )
{
service.grantDevicePermission( device, ai.uid );
service.setDevicePackage( device, YOUR_APP_PACKAGE_NAMESPACE );
}
}
}
}
catch( Exception e )
{
trace( e.toString() );
}
}
}
}
还有一件事 - 您必须在清单中添加以下权限（Lint 可能不喜欢它，但您始终可以在项目属性中更改严重级别）：
<uses-permission android:name="android.permission.MANAGE_USB" />