How to transfer input made during one activity to another activity?

Question

I am trying to transfer data from one page to another, but some problem below is the code. I am trying to pass the value of a variable using a bundle from the first activity to the second, but something is wrong, please tell me what is going wrong.

below is the first activity: -

public class login extends Activity { /** Called when the activity is first created. */ Context mCtx; final static int START =0; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); mCtx = this; Button btn = (Button)findViewById(R.id.btn); btn.setOnClickListener(new OnClickListener(){ // @Override public void onClick(View v) { String fromLat = new String(); String fromLong = new String(); String toLat = new String(); String toLong = new String(); fromLat = ((EditText)findViewById(R.id.FromLatitude)).getText().toString(); fromLong = ((EditText)findViewById(R.id.FromLongitude)).getText().toString(); toLat = ((EditText)findViewById(R.id.ToLatitude)).getText().toString(); toLong = ((EditText)findViewById(R.id.ToLongitude)).getText().toString(); Intent intent = new Intent(mCtx, MapRouteActivity.class); /*Sending some arguments*/ Bundle bundle = new Bundle(4); bundle.putString("fromLat",fromLat ); bundle.putString("fromLong",fromLong ); bundle.putString("toLat",toLat ); bundle.putString("toLong",toLong ); intent.putExtras(bundle); /*Start Activity*/ mCtx.startActivity(intent); /*Start ActivityForResult*/ ((Activity)mCtx).startActivityForResult(intent, 2); } }); } @Override protected void onActivityResult(int requestCode, int resultCode, Intent data) { // TODO Auto-generated method stub super.onActivityResult(requestCode, resultCode, data); if(requestCode == START) { Toast.makeText(mCtx, Integer.toString(resultCode), Toast.LENGTH_SHORT).show(); } } @Override public void onDestroy(){ super.onDestroy(); finish(); } } 

The second action is shown below: -

 public class MapRouteActivity extends MapActivity { LinearLayout linearLayout; MapView mapView; private Road mRoad; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.routeplanning); mapView = (MapView) findViewById(R.id.mapview); mapView.setBuiltInZoomControls(true); Bundle extras = this.getIntent().getExtras(); String fLat=extras.getString("fromLat"); String fLong=extras.getString("fromLong"); String tLat=extras.getString("toLat"); String tLong=extras.getString("toLong"); final double fromLat=Double.parseDouble(fLat); final double fromLon=Double.parseDouble(fLong); final double toLat=Double.parseDouble(tLat); final double toLon=Double.parseDouble(tLong); new Thread() { @Override public void run() { //double fromLat = 28.6353, fromLon = 77.2250, toLat = 30.7313, toLon = 76.7754; /***url contains the path to fetch the kml file from the internet*/ String url = RoadProvider .getUrl(fromLat, fromLon, toLat, toLon); InputStream is = getConnection(url); mRoad = RoadProvider.getRoute(is); mHandler.sendEmptyMessage(0); } }.start(); } Handler mHandler = new Handler() { public void handleMessage(android.os.Message msg) { TextView textView = (TextView) findViewById(R.id.description); textView.setText(mRoad.mName + " " + mRoad.mDescription); MapOverlay mapOverlay = new MapOverlay(mRoad, mapView); List<Overlay> listOfOverlays = mapView.getOverlays(); listOfOverlays.clear(); listOfOverlays.add(mapOverlay); mapView.invalidate(); }; }; private InputStream getConnection(String url) { InputStream is = null; try { //Opens a connection to the remote database(bidirectional) URLConnection conn = new URL(url).openConnection(); is = conn.getInputStream(); } catch (MalformedURLException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } return is; } @Override protected boolean isRouteDisplayed() { return false; } } class MapOverlay extends com.google.android.maps.Overlay { Road mRoad; ArrayList<GeoPoint> mPoints; public MapOverlay(Road road, MapView mv) { mRoad = road; if (road.mRoute.length > 0) { mPoints = new ArrayList<GeoPoint>(); for (int i = 0; i < road.mRoute.length; i++) { mPoints.add(new GeoPoint((int) (road.mRoute[i][1] * 1000000), (int) (road.mRoute[i][0] * 1000000))); } int moveToLat = (mPoints.get(0).getLatitudeE6() + (mPoints.get( mPoints.size() - 1).getLatitudeE6() - mPoints.get(0) .getLatitudeE6()) / 2); int moveToLong = (mPoints.get(0).getLongitudeE6() + (mPoints.get( mPoints.size() - 1).getLongitudeE6() - mPoints.get(0) .getLongitudeE6()) / 2); GeoPoint moveTo = new GeoPoint(moveToLat, moveToLong); MapController mapController = mv.getController(); mapController.animateTo(moveTo); mapController.setZoom(9); } } @Override public boolean draw(Canvas canvas, MapView mv, boolean shadow, long when) { super.draw(canvas, mv, shadow); drawPath(mv, canvas); return true; } public void drawPath(MapView mv, Canvas canvas) { int x1 = -1, y1 = -1, x2 = -1, y2 = -1; Paint paint = new Paint(); paint.setColor(Color.GREEN); paint.setStyle(Paint.Style.STROKE); paint.setStrokeWidth(3); for (int i = 0; i < mPoints.size(); i++) { Point point = new Point(); mv.getProjection().toPixels(mPoints.get(i), point); x2 = point.x; y2 = point.y; if (i > 0) { canvas.drawLine(x1, y1, x2, y2, paint); } x1 = x2; y1 = y2; } } } 

When the button is pressed, the application is forcibly closed.

The following are LogCat data for forcibly closing an application

 02-02 15:32:31.837: ERROR/AndroidRuntime(199): Uncaught handler: thread main exiting due to uncaught exception 02-02 15:32:31.857: ERROR/AndroidRuntime(199): java.lang.NullPointerException 02-02 15:32:31.857: ERROR/AndroidRuntime(199): at route.planning.login$1.onClick(login.java:49) 02-02 15:32:31.857: ERROR/AndroidRuntime(199): at android.view.View.performClick(View.java:2344) 02-02 15:32:31.857: ERROR/AndroidRuntime(199): at android.view.View.onTouchEvent(View.java:4133) 02-02 15:32:31.857: ERROR/AndroidRuntime(199): at android.widget.TextView.onTouchEvent(TextView.java:6504) 02-02 15:32:31.857: ERROR/AndroidRuntime(199): at android.view.View.dispatchTouchEvent(View.java:3672) 02-02 15:32:31.857: ERROR/AndroidRuntime(199): at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:882) 02-02 15:32:31.857: ERROR/AndroidRuntime(199): at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:882) 02-02 15:32:31.857: ERROR/AndroidRuntime(199): at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:882) 02-02 15:32:31.857: ERROR/AndroidRuntime(199): at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:882) 02-02 15:32:31.857: ERROR/AndroidRuntime(199): at com.android.internal.policy.impl.PhoneWindow$DecorView.superDispatchTouchEvent(PhoneWindow.java:1712) 02-02 15:32:31.857: ERROR/AndroidRuntime(199): at com.android.internal.policy.impl.PhoneWindow.superDispatchTouchEvent(PhoneWindow.java:1202) 02-02 15:32:31.857: ERROR/AndroidRuntime(199): at android.app.Activity.dispatchTouchEvent(Activity.java:1987) 02-02 15:32:31.857: ERROR/AndroidRuntime(199): at com.android.internal.policy.impl.PhoneWindow$DecorView.dispatchTouchEvent(PhoneWindow.java:1696) 02-02 15:32:31.857: ERROR/AndroidRuntime(199): at android.view.ViewRoot.handleMessage(ViewRoot.java:1658) 02-02 15:32:31.857: ERROR/AndroidRuntime(199): at android.os.Handler.dispatchMessage(Handler.java:99) 02-02 15:32:31.857: ERROR/AndroidRuntime(199): at android.os.Looper.loop(Looper.java:123) 02-02 15:32:31.857: ERROR/AndroidRuntime(199): at android.app.ActivityThread.main(ActivityThread.java:4203) 02-02 15:32:31.857: ERROR/AndroidRuntime(199): at java.lang.reflect.Method.invokeNative(Native Method) 02-02 15:32:31.857: ERROR/AndroidRuntime(199): at java.lang.reflect.Method.invoke(Method.java:521) 02-02 15:32:31.857: ERROR/AndroidRuntime(199): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:791) 02-02 15:32:31.857: ERROR/AndroidRuntime(199): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:549) 02-02 15:32:31.857: ERROR/AndroidRuntime(199): at dalvik.system.NativeStart.main(Native Method) 

Answer 1

What is included in line 49 login.java?

Some tips: Classes should always start with an uppercase, so Login instead of entering