启动活动时,将USB拇指驱动器安装到Android设备上

Question

我正在尝试将USB大容量存储设备安装到运行android的Raspberry Pi上.我遇到了这个答案,它展示了如何使用命令行ADB shell安装它.但问题是每次我的设备启动时都必须运行这些命令.我想在onCreate()我的发布活动中安装USB驱动器.这是代码:

//Here is the mount drive function which I called in onCreate of my activity.

 private void mountDrive() throws IOException, InterruptedException {
        Process mProcess = Runtime.getRuntime().exec("/system/xbin/su");
        BufferedReader reader = new BufferedReader(new InputStreamReader(mProcess.getInputStream()));

        DataOutputStream dos = new DataOutputStream(mProcess.getOutputStream());
        dos.writeBytes("mkdir /mnt/usb\n");
        dos.flush();
        dos.writeBytes("mount -t vfat -o rw /dev/block/sda1 /mnt/usb\n");
        dos.flush();
        dos.writeBytes("exit\n");

        //Read the response
        String line, result = "";
        while ((line = reader.readLine()) != null) {
            result += line;
            Log.d("CMD","RESULT:"+result);
        }
        reader.close();
        dos.flush();
        dos.close();

        mProcess.waitFor();
    }

但是我收到了这个错误:

I/sh: type=1400 audit(0.0:31): avc: denied { read } for name="/" dev="mmcblk0p6" ino=2 scontext=u:r:untrusted_app:s0:c512,c768 tcontext=u:object_r:rootfs:s0 tclass=dir permissive=1
I/sh: type=1400 audit(0.0:32): avc: denied { open } for path="/" dev="mmcblk0p6" ino=2 scontext=u:r:untrusted_app:s0:c512,c768 tcontext=u:object_r:rootfs:s0 tclass=dir permissive=1
W/System.err: java.io.IOException: Cannot run program "su": error=13, Permission denied
W/System.err:     at java.lang.ProcessBuilder.start(ProcessBuilder.java:983)
W/System.err:     at java.lang.Runtime.exec(Runtime.java:691)
W/System.err:     at java.lang.Runtime.exec(Runtime.java:524)
W/System.err:     at java.lang.Runtime.exec(Runtime.java:421)

如何在Android Things上使用我的应用程序安装USB设备？

Answer 1

您只能在已取得 root 权限的 Android 中运行这些命令。出于安全原因，Android Things（即 Android）不允许执行 shell 命令。