title: App Crashes when Button is clicked (Passing a string between two classes.)
body: <p>I've started on another class that get's two strings from another class, I've only set up one so far, but I just tested it out, but when I fill in my two edit text's and hit submit it crashes.</p>
  
  <p>First Class (Launcher Class)</p>
  
  <pre><code>package com.gta5news.bananaphone;
  
  import java.io.File;
  import java.io.FileNotFoundException;
  import java.io.FileOutputStream;
  import java.io.IOException;
  
  import android.R.string;
  import android.app.Activity;
  import android.content.Context;
  import android.content.Intent;
  import android.content.SharedPreferences;
  import android.os.Bundle;
  import android.os.Environment;
  import android.view.View;
  import android.view.View.OnClickListener;
  import android.widget.Button;
  import android.widget.CheckBox;
  import android.widget.EditText;
  import android.widget.TextView;
  import android.widget.Toast;
  
   public class LogIn extends Activity implements OnClickListener {
  Button send;
  EditText user;
  EditText pass;
  CheckBox staySignedIn;
  FileOutputStream Fos;
  String FILENAME = "userandpass";
  
  
  @Override
  protected void onCreate(Bundle savedInstanceState) {
      // TODO Auto-generated method stub
      super.onCreate(savedInstanceState);
      setContentView(R.layout.login);
      send = (Button) findViewById(R.id.bLogIn);
      user = (EditText) findViewById(R.id.eTuser);
      pass = (EditText) findViewById(R.id.eTpassword);
      staySignedIn = (CheckBox) findViewById(R.id.Cbstay);
      send.setOnClickListener(this);
      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();
      }
  
      if (staySignedIn.isChecked()) {
  
          String a = user.getText().toString();
          String b = pass.getText().toString();
          File f = new File(FILENAME);
          try {
              Fos = new FileOutputStream(f);
              //Write some Data
              Fos.close();
          } catch (FileNotFoundException e) {
              // TODO Auto-generated catch block
              e.printStackTrace();
          } catch (IOException e) {
              // TODO Auto-generated catch block
              e.printStackTrace();
          } 
  
  
      } 
  
  }
  
  public void onClick(View v) {
      // TODO Auto-generated method stub
      switch (v.getId()) {
      case R.id.bLogIn:
          if (pass.length() == 0)
              Toast.makeText(this,
                      "Try to type in your username and password again!",
                      Toast.LENGTH_LONG).show();
          else if (user.length() == 0)
              Toast.makeText(this,
                      "Try to type in your username and password again!",
                      Toast.LENGTH_LONG).show();
          else {
  
              String u = user.getText().toString();
              String p = pass.getText().toString();
              Bundle send = new Bundle();
              send.putString("key", u);
              send.putString("key", p);
              Intent a = new Intent(LogIn.this, logincheck.class);
              startActivity(a);
              Toast.makeText(this, "Were signing you in!", Toast.LENGTH_LONG)
                      .show();
              break;
          }
      }
  
  }
  }
  </code></pre>
  
  <p>Second Class:</p>
  
  <pre><code>package com.gta5news.bananaphone;
  
  import android.app.Activity;
  import android.os.Bundle;
  import android.widget.TextView;
  
  public class logincheck extends Activity {
  String GotBread;
  TextView user;
  
  @Override
  protected void onCreate(Bundle savedInstanceState) {
      // TODO Auto-generated method stub
      super.onCreate(savedInstanceState);
      setContentView(R.layout.logincheck);
      user = (TextView) findViewById(R.layout.logincheck);
      SetUp();
  
  }
  
  public void SetUp() {
      // TODO Auto-generated method stub
      Bundle GotData = getIntent().getExtras();
      GotBread = GotData.getString("key");
      user.setText(GotBread); {
  
  
  }
  
  }
  }
  </code></pre>
  
  <p>LogCat:</p>
  
  <pre><code>01-19 08:53:56.641: E/AndroidRuntime(3319):     ... 11 more
  01-19 08:56:28.561: E/AndroidRuntime(3384): FATAL EXCEPTION: main
  01-19 08:56:28.561: E/AndroidRuntime(3384): java.lang.RuntimeException: Unable to start  activity ComponentInfo{com.gta5news.bananaphone/com.gta5news.bananaphone.logincheck}: java.lang.NullPointerException
  01-19 08:56:28.561: E/AndroidRuntime(3384):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2663)
  01-19 08:56:28.561: E/AndroidRuntime(3384):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2679)
  01-19 08:56:28.561: E/AndroidRuntime(3384):     at android.app.ActivityThread.access$2300(ActivityThread.java:125)
  01-19 08:56:28.561: E/AndroidRuntime(3384):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2033)
  01-19 08:56:28.561: E/AndroidRuntime(3384):     at android.os.Handler.dispatchMessage(Handler.java:99)
  01-19 08:56:28.561: E/AndroidRuntime(3384):     at android.os.Looper.loop(Looper.java:123)
  01-19 08:56:28.561: E/AndroidRuntime(3384):     at android.app.ActivityThread.main(ActivityThread.java:4627)
  01-19 08:56:28.561: E/AndroidRuntime(3384):     at java.lang.reflect.Method.invokeNative(Native Method)
  01-19 08:56:28.561: E/AndroidRuntime(3384):     at java.lang.reflect.Method.invoke(Method.java:521)
   01-19 08:56:28.561: E/AndroidRuntime(3384):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
  01-19 08:56:28.561: E/AndroidRuntime(3384):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
  01-19 08:56:28.561: E/AndroidRuntime(3384):     at dalvik.system.NativeStart.main(Native Method)
  01-19 08:56:28.561: E/AndroidRuntime(3384): Caused by: java.lang.NullPointerException
  01-19 08:56:28.561: E/AndroidRuntime(3384):     at com.gta5news.bananaphone.logincheck.SetUp(logincheck.java:24)
  01-19 08:56:28.561: E/AndroidRuntime(3384):     at com.gta5news.bananaphone.logincheck.onCreate(logincheck.java:17)
  01-19 08:56:28.561: E/AndroidRuntime(3384):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
  01-19 08:56:28.561: E/AndroidRuntime(3384):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2627)
  01-19 08:56:28.561: E/AndroidRuntime(3384):     ... 11 more
  </code></pre>