Develop Reference

Android Read/Write XML file Data Error

I am trying to create an XML file that will store the variable T1 or the TextOne EditText but I am unsure if I am doing it correctly in this code below. I am also trying to figure out how I can read the created xml file and display the T1 variable into another EditText.
package com.example.treasurehunt;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.StringWriter;
import org.xmlpull.v1.XmlSerializer;
import android.app.Activity;
import android.content.Context;
import android.os.Bundle;
import android.util.Xml;
import android.view.Menu;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
public class CreateTreasure extends Activity {
//variables
EditText TextOne, TextTwo, TextThree, TextFour, TextFive;
Button SaveTreasure;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_create_treasure);
TextOne = (EditText) findViewById(R.id.EditTextOne);
final String T1 = TextOne.getText().toString();
SaveTreasure = (Button) findViewById(R.id.SaveTreasuresButton);
//onclick
SaveTreasure.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
final String xmlFile="TreasureList";
FileOutputStream fileos;
try {
fileos = getApplicationContext().openFileOutput(xmlFile, Context.MODE_APPEND);
XmlSerializer xmlSerializer = Xml.newSerializer();
StringWriter writer = new StringWriter();
xmlSerializer.setOutput(writer);
xmlSerializer.startDocument("UTF-8",true);
xmlSerializer.startTag(null, "TreasureList");
xmlSerializer.startTag(null, "TreasureOne");
xmlSerializer.text(T1);
xmlSerializer.endTag(null,"TreasureOne");
xmlSerializer.endTag(null, "TreasureList");
xmlSerializer.endDocument();
xmlSerializer.flush();
String dataWrite=writer.toString();
fileos.write(dataWrite.getBytes());
fileos.close();
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IllegalArgumentException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IllegalStateException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
});
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.create_treasure, menu);
return true;
}
}

udp connecting to device

here is my Code
package com.example.messenger;
import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.net.SocketException;
import java.net.UnknownHostException;
import android.annotation.SuppressLint;
import android.app.Activity;
import android.os.Bundle;
import android.os.StrictMode;
import android.view.Menu;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
#SuppressLint("NewApi")
public class MainActivity extends Activity implements View.OnClickListener {
Button Send;
EditText IPAdresse;
EditText TEXT;
TextView RXtext,tstep,rstep;
private static final int TIMEOUT_MS = 1000;
private static final int server_port = 13011;
#SuppressLint({ "NewApi", "NewApi", "NewApi" })
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
StrictMode.setThreadPolicy(policy);
IPAdresse = (EditText) findViewById(R.id.etIPAdresse);
IPAdresse.setText("192.168.2.32");
TEXT = (EditText) findViewById(R.id.etTEXT);
Send = (Button) findViewById(R.id.bSendaa);
RXtext = (TextView) findViewById(R.id.tvRXtext);
tstep = (TextView) findViewById(R.id.tvTstep);
rstep = (TextView) findViewById(R.id.tvRstep);
Send.setOnClickListener(this);
new Thread(new Runnable() {
#Override
public void run() {
// TODO Auto-generated method stub
String text;
byte[] message = new byte[1500];
DatagramSocket s;
while(true){
try {
s= new DatagramSocket(server_port);
rstep.setText("1");
s.setBroadcast(true);
rstep.setText("2");
s.setSoTimeout(TIMEOUT_MS);
rstep.setText("3");
while(true){
DatagramPacket p = new DatagramPacket(message, message.length);
rstep.setText("4");
//InetAddress test = InetAddress.getByName("192.168.1.101");
//rstep.setText("5");
//s.connect(test,12345);
//rstep.setText("6");
s.receive(p);
rstep.setText("xxx");
text = new String(message, 0, p.getLength());
RXtext.setText(text);
}
} catch (SocketException e) {
// TODO Auto-generated catch block
e.printStackTrace();
rstep.setText("fail socket create");
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
rstep.setText("fail receive");
}
}
}
});
}
public void onClick(View arg0) {
// TODO Auto-generated method stub
switch(arg0.getId()){
case R.id.bSendaa:
tstep.setText("1");
String messageStr= TEXT.getText().toString();
tstep.setText("2");
DatagramSocket s;
try {
s = new DatagramSocket();
tstep.setText("3");
s.setBroadcast(true);
tstep.setText("4");
s.setSoTimeout(TIMEOUT_MS);
tstep.setText("5");
InetAddress local = InetAddress.getByName(IPAdresse.getText().toString());
tstep.setText("6");
int msg_length=messageStr.length();
tstep.setText("7");
byte[] message = messageStr.getBytes();
tstep.setText("8");
DatagramPacket p = new DatagramPacket(message, msg_length,local,server_port);
tstep.setText("9");
s.connect(local,server_port);
tstep.setText("10");
s.send(p);
tstep.setText("sending complete");
} catch (SocketException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (UnknownHostException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
tstep.setText("sending failed");
}
}
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.activity_main, menu);
return true;
}
}
My android phone's Ip is 192.168.2.32 , I saw it in wifi settings. So when I debug it row by row , I saw that my virtual device sent the packet , but I don't know why my phone can't get it. Can anybody help me?
Thanks
Regards

now it works , I didn't call start() function for thread , and I should change the UI from runOnUiThread , but it worked only from device to device, not from Virtual Device to Device, so here is the working code
package com.example.messenger;
import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.net.SocketAddress;
import java.net.SocketException;
import java.net.UnknownHostException;
import android.annotation.SuppressLint;
import android.app.Activity;
import android.os.Bundle;
import android.os.StrictMode;
import android.view.Menu;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
#SuppressLint("NewApi")
public class MainActivity extends Activity implements View.OnClickListener {
Button Send;
EditText IPAdresse;
EditText TEXT;
TextView RXtext,tstep,rstep;
private static final int TIMEOUT_MS = 10000;
private static final int server_port = 13011;
String mMessage;
#SuppressLint({ "NewApi", "NewApi", "NewApi" })
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
StrictMode.setThreadPolicy(policy);
IPAdresse = (EditText) findViewById(R.id.etIPAdresse);
IPAdresse.setText("192.168.2.32");
TEXT = (EditText) findViewById(R.id.etTEXT);
Send = (Button) findViewById(R.id.bSendaa);
RXtext = (TextView) findViewById(R.id.tvRXtext);
tstep = (TextView) findViewById(R.id.tvTstep);
rstep = (TextView) findViewById(R.id.tvRstep);
Send.setOnClickListener(this);
new Thread(new Runnable() {
#Override
public void run() {
// TODO Auto-generated method stub
String text;
byte[] message = new byte[4];
DatagramSocket s;
try {
s= new DatagramSocket(server_port);
s.setSoTimeout(TIMEOUT_MS);
while(true){
try {
DatagramPacket p = new DatagramPacket(message, message.length);
s.receive(p);
mMessage = new String(message, 0, p.getLength());
runOnUiThread(new Runnable() {
#Override
public void run() {
RXtext.setText(mMessage);
}
});
}
catch(Exception e) {
e.printStackTrace();
}
}
} catch (SocketException e) {
// TODO Auto-generated catch block
e.printStackTrace();
//rstep.setText("fail socket create");
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
//rstep.setText("fail receive");
}
}
}).start();
}
public void onClick(View arg0) {
// TODO Auto-generated method stub
switch(arg0.getId()){
case R.id.bSendaa:
String messageStr= TEXT.getText().toString();
DatagramSocket s;
try {
s = new DatagramSocket();
s.setBroadcast(true);
s.setSoTimeout(TIMEOUT_MS);
InetAddress local = InetAddress.getByName(IPAdresse.getText().toString());
int msg_length=messageStr.length();
byte[] message = messageStr.getBytes();
DatagramPacket p = new DatagramPacket(message, msg_length,local,server_port);
//s.connect(local,server_port);
s.send(p);
tstep.setText("sending complete");
} catch (SocketException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (UnknownHostException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
tstep.setText("sending failed");
}
}
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.activity_main, menu);
return true;
}
}

Applications crashes in 3.0 but works fine in 2.3.3

Hi guys im trying to create a application that uses a socket connection i was going across some examples, the piece of code below works fine when i run it on 2.3.3 and the same crashes in 3.0.
package com.simple.client;
import android.app.Activity;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.net.Socket;
import java.net.UnknownHostException;
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.os.Bundle;
public class SimpleClientActivity extends Activity {
EditText textOut;
TextView textIn;
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
textOut = (EditText)findViewById(R.id.textout);
Button buttonSend = (Button)findViewById(R.id.send);
textIn = (TextView)findViewById(R.id.textin);
buttonSend.setOnClickListener(buttonSendOnClickListener);
}
Button.OnClickListener buttonSendOnClickListener
= new Button.OnClickListener(){
public void onClick(View arg0) {
// TODO Auto-generated method stub
Socket socket = null;
DataOutputStream dataOutputStream = null;
DataInputStream dataInputStream = null;
try {
socket = new Socket("172.16.2.172", 8899);
dataOutputStream = new DataOutputStream(socket.getOutputStream());
dataInputStream = new DataInputStream(socket.getInputStream());
dataOutputStream.writeUTF(textOut.getText().toString());
textIn.setText(dataInputStream.readUTF());
} catch (UnknownHostException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
e.printStackTrace();
}
finally{
if (socket != null){
try {
socket.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
if (dataOutputStream != null){
try {
dataOutputStream.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
if (dataInputStream != null){
try {
dataInputStream.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}};
}
I have tried all but not able to figure out what is happening,

My guess is, the error caused by StrictMode.ThreadPolicy. In android 3.0, you can't access network in the same UI thread.

Do you have multiple resource folders for your layouts? if yes, maybe you do not have its related layout.

Using internal storage to store credentials Android

I'm trying to permanently store three strings as user preferences for my Android application. These three strings are a url, username, and password. I don't really understand SharedPreferences, so I tried to use internal file storage. I'm not able to retrieve the three strings from the file, and I get a runtime error. I know I probably coded something wrong, but I'm just not proficient enough in Android to understand data storage. Could somebody help me out?
Preferences activity:
package com.amritayalur.mypowerschool;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.content.SharedPreferences.Editor;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
public class MyPowerSchoolActivity extends Activity {
Button buttonSubmit;
TextView textViewTitle;
TextView textViewDesc;
EditText editTextURL, editTextUser, editTextPass;
FileOutputStream fos;
String url = "";
String FILENAME = "InternalStrings";
String str;
String username;
String password;
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
buttonSubmit = (Button) findViewById(R.id.buttonSubmit);
textViewTitle = (TextView) findViewById(R.id.textViewTitle);
textViewDesc = (TextView) findViewById(R.id.textViewDesc);
editTextURL = (EditText) findViewById(R.id.editTextURL);
editTextUser = (EditText) findViewById(R.id.editTextUser);
editTextPass = (EditText) findViewById(R.id.editTextPass);
//Start TextView
textViewTitle.setText("MyPowerSchool");
try {
fos = openFileOutput(FILENAME, Context.MODE_PRIVATE);
fos.close();
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
//button listener
buttonSubmit.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v)
{
if ( ( !editTextURL.getText().toString().equals("")) && (
!editTextUser.getText().toString().equals("")) && (
!editTextPass.getText().toString().equals("") ) )
{
url = editTextURL.getText().toString();
username = editTextUser.getText().toString();
password = editTextPass.getText().toString();
//Saving data via File
/* File f = new File(FILENAME);
try {
fos = new FileOutputStream(f);
fos.close();
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
*/
try {
fos = openFileOutput(FILENAME, Context.MODE_PRIVATE);
fos.write(url.getBytes());
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
try {
fos.write(username.getBytes());
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
try {
fos.write(password.getBytes());
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
try {
fos.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
// TODO Auto-generated method stub
Intent i = new Intent( MyPowerSchoolActivity.this,
creds.class);
//i.putExtra("pschoolurl", editTextURL.getText().toString());
//i.putExtra("pschooluser", editTextUser.getText().toString());
//i.putExtra("pschoolpass", editTextPass.getText().toString());
// get the text here
final int result = 1;
startActivityForResult(i, result);
}
};
});}}
Activity in which I am trying to retrieve credentials:
package com.amritayalur.mypowerschool;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.widget.TextView;
public class creds extends Activity {
String url;
String username;
String password;
TextView TextViewTest;
String FILENAME = "InternalStrings";
;
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.second);
Intent intent = getIntent();
//String url = intent.getExtras().getString("pschoolurl");
//String username = intent.getExtras().getString("pschooluser");
//String password = intent.getExtras().getString("pschoolpass");
String collected = null;
FileInputStream fis = null;
try {
fis = openFileInput(FILENAME);
byte[] dataArray = new byte[fis.available()];
while (fis.read(dataArray) != -1 ){
collected = new String(dataArray);
}
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} finally {
try {
fis.close();
TextViewTest.setText(collected);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}
The commented text is a result of me trying to mess around with different aspects of the code.

SharedPreferences is not too difficult.
To add something to the preferences:
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(MyActivity.this); //Get the preferences
Editor edit = prefs.edit(); //Needed to edit the preferences
edit.putString("name", "myname"); //add a String
edit.putBoolean("rememberCredentials", true); //add a boolean
edit.commit(); // save the edits.
To read something:
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(MyActivity.this); //Get the preferences
String name = prefs.getString("name", "defaultName"); //get a String
boolean rememberCredentials = prefs.getBoolean("rememberCredentials", true); //get a boolean.
//When the key "rememberCredentials" is not present, true is returned.

Problem opening a Socket

I'm building a very small app to send data from the cellphone to a computer. I've read a couple of examples and got the server and client code working. But when i try to connect them, got a "network unreachable" error. Any idea what am i doing wrong??
This is the Server Code:
import java.net.*;
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.io.*;
import javax.swing.JFrame;
import javax.swing.JLabel;
public class Server {
static BufferedReader in = null;
static Socket clientSocket = null;
static ServerSocket serverSocket = null;
public static void main(String[] args) throws IOException {
JFrame frame = new JFrame("FrameDemo");
frame.addWindowListener(new WindowAdapter()
{
public void windowClosing(WindowEvent e)
{
try {
if (in != null)
in.close();
if (serverSocket.isClosed())
{}
else
serverSocket.close();
} catch (IOException e1) {
e1.printStackTrace();
}
}
});
JLabel Label = new JLabel("");
Label.setPreferredSize(new Dimension(175, 100));
frame.getContentPane().add(Label, BorderLayout.CENTER);
//Display the window.
frame.pack();
frame.setVisible(true);
Label.setText("Empezo");
serverSocket = null;
try {
serverSocket = new ServerSocket(4444);
} catch (IOException e) {
System.err.println("Could not listen on port: 4444.");
System.err.println(e.getMessage());
System.exit(1);
}
Integer puerto = serverSocket.getLocalPort();
Label.setText("<html>Puerto Abierto: " + puerto.toString() + "<br>IP Servidor: " + serverSocket.getInetAddress().toString() + "</html>");
clientSocket = null;
try {
clientSocket = serverSocket.accept();
Label.setText("Conection Accepted");
} catch (IOException e) {
System.err.println("Accept failed.");
System.exit(1);
}
in = new BufferedReader(
new InputStreamReader(
clientSocket.getInputStream()));
while ((in.readLine()) != null) {
System.out.println("Mensaje: " + in.readLine());
}
}
}
And the Cliente part
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;
import java.io.IOException;
import java.io.PrintWriter;
import java.net.Socket;
public class PruebaSocket extends Activity {
/** Called when the activity is first created. */
Socket Skt;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
Button Enviar =(Button)findViewById(R.id.OK);
Button Salir = (Button)findViewById(R.id.SALIR);
final TextView IP = (TextView)findViewById(R.id.IP);
Skt = new Socket();
Enviar.setOnClickListener(new OnClickListener(){
public void onClick(View v) {
try{
Skt = new Socket("192.168.1.101",4444);
CharSequence errorMessage = "Coneccted";
Toast.makeText(PruebaSocket.this, errorMessage, Toast.LENGTH_SHORT).show();
}
catch(Exception E)
{
CharSequence errorMessage = E.getMessage();
Toast.makeText(PruebaSocket.this, errorMessage, Toast.LENGTH_SHORT).show();
if (Skt.isConnected())
try {
Skt.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
});
Salir.setOnClickListener(new OnClickListener(){
#Override
public void onClick(View arg0) {
try {
Skt.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
);
}
}
192.168.1.101 it's the IP of the server.

I don't know much about java sockets but the normal usage of a socket is: create, bind, and put in listen mode (udp) or call .accept() (tcp). I can see Java also has the binding phase - http://download.oracle.com/javase/1.5.0/docs/api/java/net/ServerSocket.html#bind(java.net.SocketAddress, int).