two nodes on ros android

edit

You can run any number of nodes within an activity. Simply do something like this (assuming your activity is a RosActivity):

@Override
protected void init(NodeMainExecutor nodeMainExecutor) {
    NodeConfiguration nodeConfiguration = NodeConfiguration.newPublic(getRosHostname());
    nodeConfiguration.setMasterUri(getMasterUri());

    nodeConfiguration.setNodeName("node_1");
    MyNode myNode1 = new MyNode();     // Something that extends AbstractNodeMain
    nodeMainExecutor.execute(myNode1, nodeConfiguration);

    nodeConfiguration.setNodeName("node_2");
    MyNode myNode2 = new MyNode();
    nodeMainExecutor.execute(myNode2, nodeConfiguration);     // And so on...
}