Android usb设备权限查询及自动获取详解流程

看到当上面的对话框弹出时，可以使用命令查看顶层的活动窗口

adb shell dumpsys window | findstr mCurrentFocus
mCurrentFocus=Window{41ab0ee0 u0 com.android.systemui/com.android.systemui.usb.UsbPermissionActivity}

这就是应用的位置，当然我们也可以是用grep命令来查找这个对话框的.xml文件，进入android源码然后输入命令：

grep '默认情况下用于' ./ -Rn
./SystemUI/res/values-zh-rCN/strings.xml:51:    <string name="always_use_device" msgid="1450287437017315906">"默认情况下用于该 USB 设备"</string>
./SystemUI/res/values-zh-rCN/strings.xml:52:    <string name="always_use_accessory" msgid="1210954576979621596">"默认情况下用于该 USB 配件"</string>

那么这个对话框的路径在

/android/frameworks/base/packages/SystemUI/res/values-zh-rCN/strings.xml

其相关的内容如下：

<string name="always_use_device" msgid="1450287437017315906">"默认情况下用于该 USB 设备"</string>

<string name="usb_device_permission_prompt" msgid="834698001271562057">"允许应用“<xliff:g id="APPLICATION">％1$s</xliff:g>”访问该 USB 设备吗？"

相关应用路径找到.java文件来修改，其位置在:

/android/frameworks/base/packages/SystemUI/src/com/android/systemui/usb/UsbPermissionActivity.java

这就是那个讨厌的对话框对应的java程序，那么来看看这个程序如下：

/*
* Copyright (C) 2011 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
*      http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/

package com.android.systemui.usb;

import android.app.AlertDialog;
import android.app.PendingIntent;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.pm.ApplicationInfo;
import android.content.pm.PackageManager;
import android.hardware.usb.IUsbManager;
import android.hardware.usb.UsbAccessory;
import android.hardware.usb.UsbDevice;
import android.hardware.usb.UsbManager;
import android.os.Bundle;
import android.os.IBinder;
import android.os.RemoteException;
import android.os.ServiceManager;
import android.os.UserHandle;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.widget.CheckBox;
import android.widget.CompoundButton;
import android.widget.TextView;

import com.android.internal.app.AlertActivity;
import com.android.internal.app.AlertController;
import com.android.systemui.R;

public class UsbPermissionActivity extends AlertActivity
       implements DialogInterface.OnClickListener, CheckBox.OnCheckedChangeListener {

private static final String TAG = "UsbPermissionActivity";

private CheckBox mAlwaysUse;
   private TextView mClearDefaultHint;
   private UsbDevice mDevice;
   private UsbAccessory mAccessory;
   private PendingIntent mPendingIntent;
   private String mPackageName;
   private int mUid;
   private boolean mPermissionGranted;
   private UsbDisconnectedReceiver mDisconnectedReceiver;

@Override
   public void onCreate(Bundle icicle) {
       super.onCreate(icicle);

Intent intent = getIntent();
       mDevice = (UsbDevice)intent.getParcelableExtra(UsbManager.EXTRA_DEVICE);
       mAccessory = (UsbAccessory)intent.getParcelableExtra(UsbManager.EXTRA_ACCESSORY);
       mPendingIntent = (PendingIntent)intent.getParcelableExtra(Intent.EXTRA_INTENT);
       mUid = intent.getIntExtra(Intent.EXTRA_UID, -1);
       mPackageName = intent.getStringExtra("package");
       Log.e(TAG, "mPackageName   "+ mPackageName);
Log.e(TAG, "mUid   "+ mUid);
       PackageManager packageManager = getPackageManager();
       ApplicationInfo aInfo;
       try {
           aInfo = packageManager.getApplicationInfo(mPackageName, 0);
       } catch (PackageManager.NameNotFoundException e) {
           Log.e(TAG, "unable to look up package name", e);
           finish();
           return;
       }
       String appName = aInfo.loadLabel(packageManager).toString();
       Log.e(TAG, "appName   "+ appName);
       final AlertController.AlertParams ap = mAlertParams;
       ap.mIcon = aInfo.loadIcon(packageManager);
       ap.mTitle = appName;
       if (mDevice == null) {
           ap.mMessage = getString(R.string.usb_accessory_permission_prompt, appName);
           mDisconnectedReceiver = new UsbDisconnectedReceiver(this, mAccessory);
       } else {
           ap.mMessage = getString(R.string.usb_device_permission_prompt, appName);
           mDisconnectedReceiver = new UsbDisconnectedReceiver(this, mDevice);
       }
       ap.mPositiveButtonText = getString(android.R.string.ok);
       ap.mNegativeButtonText = getString(android.R.string.cancel);
       ap.mPositiveButtonListener = this;
       ap.mNegativeButtonListener = this;

// add "always use" checkbox
       LayoutInflater inflater = (LayoutInflater)getSystemService(
               Context.LAYOUT_INFLATER_SERVICE);
       ap.mView = inflater.inflate(com.android.internal.R.layout.always_use_checkbox, null);
       mAlwaysUse = (CheckBox)ap.mView.findViewById(com.android.internal.R.id.alwaysUse);
       if (mDevice == null) {
           mAlwaysUse.setText(R.string.always_use_accessory);
       } else {
           mAlwaysUse.setText(R.string.always_use_device);
       }
       mAlwaysUse.setOnCheckedChangeListener(this);
       mClearDefaultHint = (TextView)ap.mView.findViewById(
                                                   com.android.internal.R.id.clearDefaultHint);
       mClearDefaultHint.setVisibility(View.GONE);

if(!mPackageName.equals("com.zqc.usbcamera"))
setupAlert();
else
{
mPermissionGranted = true;
finish();
}

}

@Override
   public void onDestroy() {
       IBinder b = ServiceManager.getService(USB_SERVICE);
       IUsbManager service = IUsbManager.Stub.asInterface(b);

// send response via pending intent
       Intent intent = new Intent();
       try {
           if (mDevice != null) {
               intent.putExtra(UsbManager.EXTRA_DEVICE, mDevice);
               if (mPermissionGranted) {
                   service.grantDevicePermission(mDevice, mUid);
                   if (mAlwaysUse.isChecked()) {
                       final int userId = UserHandle.getUserId(mUid);
                       service.setDevicePackage(mDevice, mPackageName, userId);
                   }
               }
           }
           if (mAccessory != null) {
               intent.putExtra(UsbManager.EXTRA_ACCESSORY, mAccessory);
               if (mPermissionGranted) {
                   service.grantAccessoryPermission(mAccessory, mUid);
                   if (mAlwaysUse.isChecked()) {
                       final int userId = UserHandle.getUserId(mUid);
                       service.setAccessoryPackage(mAccessory, mPackageName, userId);
                   }
               }
           }
           intent.putExtra(UsbManager.EXTRA_PERMISSION_GRANTED, mPermissionGranted);
           mPendingIntent.send(this, 0, intent);
       } catch (PendingIntent.CanceledException e) {
           Log.w(TAG, "PendingIntent was cancelled");
       } catch (RemoteException e) {
           Log.e(TAG, "IUsbService connection failed", e);
       }

if (mDisconnectedReceiver != null) {
           unregisterReceiver(mDisconnectedReceiver);
       }
       super.onDestroy();
   }

public void onClick(DialogInterface dialog, int which) {
       if (which == AlertDialog.BUTTON_POSITIVE) {
           mPermissionGranted = true;
       }
       finish();
   }

public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
       if (mClearDefaultHint == null) return;

if(isChecked) {
           mClearDefaultHint.setVisibility(View.VISIBLE);
       } else {
           mClearDefaultHint.setVisibility(View.GONE);
       }
   }
}

这段代码是获取应用的包名，我们可以通过包名对比来决定是否弹出对话框。

final AlertController.AlertParams ap = mAlertParams;
       ap.mIcon = aInfo.loadIcon(packageManager);
       ap.mTitle = appName;
       if (mDevice == null) {
           ap.mMessage = getString(R.string.usb_accessory_permission_prompt, appName);
           mDisconnectedReceiver = new UsbDisconnectedReceiver(this, mAccessory);
       } else {
           ap.mMessage = getString(R.string.usb_device_permission_prompt, appName);
           mDisconnectedReceiver = new UsbDisconnectedReceiver(this, mDevice);
       }
       ap.mPositiveButtonText = getString(android.R.string.ok);
       ap.mNegativeButtonText = getString(android.R.string.cancel);
       ap.mPositiveButtonListener = this;
       ap.mNegativeButtonListener = this;

// add "always use" checkbox
       LayoutInflater inflater = (LayoutInflater)getSystemService(
               Context.LAYOUT_INFLATER_SERVICE);
       ap.mView = inflater.inflate(com.android.internal.R.layout.always_use_checkbox, null);
       mAlwaysUse = (CheckBox)ap.mView.findViewById(com.android.internal.R.id.alwaysUse);
       if (mDevice == null) {
           mAlwaysUse.setText(R.string.always_use_accessory);
       } else {
           mAlwaysUse.setText(R.string.always_use_device);
       }
       mAlwaysUse.setOnCheckedChangeListener(this);
       mClearDefaultHint = (TextView)ap.mView.findViewById(
                                                   com.android.internal.R.id.clearDefaultHint);
       mClearDefaultHint.setVisibility(View.GONE);

在上面的代码就是对话框了，接下来就是要修该的东西了

setupAlert();

如果不需要显示对话框就可以这样修改，根据包名来判断该应用是否弹出

if(!mPackageName.equals("包名"))
setupAlert();
else {
mPermissionGranted = true;
finish();
}

最终给该应用授权USB设备权限的代码，是通过调用grantDevicePermission()和grantAccessoryPermission()方法给该应用授权USB设备权限

@Override
   public void onDestroy() {
       IBinder b = ServiceManager.getService(USB_SERVICE);
       IUsbManager service = IUsbManager.Stub.asInterface(b);

// send response via pending intent
       Intent intent = new Intent();
       try {
           if (mDevice != null) {
               intent.putExtra(UsbManager.EXTRA_DEVICE, mDevice);
               if (mPermissionGranted) {
                   service.grantDevicePermission(mDevice, mUid);
                   if (mAlwaysUse.isChecked()) {
                       final int userId = UserHandle.getUserId(mUid);
                       service.setDevicePackage(mDevice, mPackageName, userId);
                   }
               }
           }
           if (mAccessory != null) {
               intent.putExtra(UsbManager.EXTRA_ACCESSORY, mAccessory);
               if (mPermissionGranted) {
                   service.grantAccessoryPermission(mAccessory, mUid);
                   if (mAlwaysUse.isChecked()) {
                       final int userId = UserHandle.getUserId(mUid);
                       service.setAccessoryPackage(mAccessory, mPackageName, userId);
                   }
               }
           }
           intent.putExtra(UsbManager.EXTRA_PERMISSION_GRANTED, mPermissionGranted);
           mPendingIntent.send(this, 0, intent);
       } catch (PendingIntent.CanceledException e) {
           Log.w(TAG, "PendingIntent was cancelled");
       } catch (RemoteException e) {
           Log.e(TAG, "IUsbService connection failed", e);
       }

if (mDisconnectedReceiver != null) {
           unregisterReceiver(mDisconnectedReceiver);
       }
       super.onDestroy();
   }

日志打印

C:\Users\Android1>adb shell logcat -s UsbPermissionActivity
--------- beginning of /dev/log/system
--------- beginning of /dev/log/main
E/UsbPermissionActivity( 708): mPackageName com.test.usbcamera
E/UsbPermissionActivity( 708): mUid 10018
E/UsbPermissionActivity( 708): appName USBCamera
E/UsbPermissionActivity( 708): onDestroy() grantDevicePermission false
E/UsbPermissionActivity( 708): mPackageName com.zqc.usbcamera
E/UsbPermissionActivity( 708): mUid 10019
E/UsbPermissionActivity( 708): appName USBCamera
E/UsbPermissionActivity( 708): onDestroy() grantDevicePermission false

来源：https://blog.csdn.net/wq892373445/article/details/121027914