su access android

Question

I'm trying to make a file browser (specifically I started changing this: http://android-er.blogspot.com.es/2010/01/implement-simple-file-explorer-in.html ).

My question is: How do I get access and see the files in the directory "/"? I found out there looking for the famous: Runtime.getRuntime().exec("su"); but I only do that superuser give permissions for admin and stop working.

I followed the steps here to root emulator: How to get root access on Android emulator? . Anyway my phone is rooted and does not work.

This is the code. The application is in superuser´s list but always get the message folder can not be read!

public class AndroidExplorer extends ListActivity {

private List<String> item = null;
private List<String> path = null;
private String root="/";
private TextView myPath;

/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main); 

    List<String> cmds = new ArrayList<String>();
    cmds.add("mount -o rw,remount /system");
    try {
        doCmds(cmds);
    } catch (Exception e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
    myPath = (TextView)findViewById(R.id.path);
    getDir(root);
}

public void doCmds(List<String> cmds) throws Exception {
    Process process = Runtime.getRuntime().exec("su");
    DataOutputStream os = new DataOutputStream(process.getOutputStream());

    for (String tmpCmd : cmds) {
            os.writeBytes(tmpCmd+"\n");
    }

    os.writeBytes("exit\n");
    os.flush();
    os.close();

    process.waitFor();
} 

private void getDir(String dirPath)
{
 myPath.setText("Location: " + dirPath);
 item = new ArrayList<String>();
 path = new ArrayList<String>();
 File f = new File(dirPath);
 File[] files = f.listFiles();

 if(!dirPath.equals(root))
 {
  item.add(root);
  path.add(root);
  item.add("../");
  path.add(f.getParent());
 }
 for(int i=0; i < files.length; i++)
 {
   File file = files[i];
   path.add(file.getPath());
   if(file.isDirectory())
    item.add(file.getName() + "/");
   else
    item.add(file.getName());
 }
 ArrayAdapter<String> fileList =
  new ArrayAdapter<String>(this, R.layout.row, item);
 setListAdapter(fileList);
}

 @Override
 protected void onListItemClick(ListView l, View v, int position, long id) {
  File file = new File(path.get(position));
  if (file.isDirectory())
  {
   if(file.canRead())
    getDir(path.get(position));
   else
   {
    new AlertDialog.Builder(this)
    .setIcon(R.drawable.ic_launcher)
    .setTitle("[" + file.getName() + "] folder can't be read!")
    .setPositiveButton("OK", 
      new DialogInterface.OnClickListener() {
       @Override
       public void onClick(DialogInterface dialog, int which) {
        // TODO Auto-generated method stub
       }
      }).show();
   }
  }
  else
  {
   new AlertDialog.Builder(this)
    .setIcon(R.drawable.ic_launcher)
    .setTitle("[" + file.getName() + "]")
    .setPositiveButton("OK", 
      new DialogInterface.OnClickListener() {
       @Override
       public void onClick(DialogInterface dialog, int which) {
        // TODO Auto-generated method stub
       }
      }).show();
  }
 }

}

Answer 1

Anyway my phone is rooted and does not work.

To start with you need a working rooted phone. Rooting method depends on your phone model so you need to google it and figure it out.

Once you have rooted your phone successfully, you will have super user rights and you will be able to execute su commands.

You can check if your phone is rooted properly like this(in windows command prompt):

> adb shell
$ su

And you should be able to see the files on root folder for example like this:

$ cd /
$ ls -al

EDIT

Replace:

Runtime r = Runtime.getRuntime();
process = r.exec("su");

With the following:

List<String> cmds = new List<String>();
cmds.add("mount -o rw,remount /system");
doCmds(cmds);

And add the following function:

public void doCmds(List<String> cmds) throws Exception {
    Process process = Runtime.getRuntime().exec("su");
    DataOutputStream os = new DataOutputStream(process.getOutputStream());

    for (String tmpCmd : cmds) {
            os.writeBytes(tmpCmd+"\n");
    }

    os.writeBytes("exit\n");
    os.flush();
    os.close();

    process.waitFor();
}