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Android accelerometer for measuring speed

im trying to make a speedometer with an accelerometer, but for some reason someone might crash the code, please tell me what is wrong and how to fix it thanks

this is the red part in logcat:

05-14 13:03:55.826: INFO/ActivityManager(91): Start proc com.hanud.speedo for activity com.hanud.speedo/.speedometer: pid=2052 uid=10127 gids={} 05-14 13:03:56.806: DEBUG/AndroidRuntime(2052): Shutting down VM 05-14 13:03:56.806: WARN/dalvikvm(2052): threadid=1: thread exiting with uncaught exception (group=0x400207f0) 05-14 13:03:56.986: ERROR/AndroidRuntime(2052): FATAL EXCEPTION: main 05-14 13:03:56.986: ERROR/AndroidRuntime(2052): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.hanud.speedo/com.hanud.speedo.speedometer}: java.lang.ClassNotFoundException: com.hanud.speedo.speedometer in loader dalvik.system.PathClassLoader[/data/app/com.hanud.speedo-2.apk] 05-14 13:03:56.986: ERROR/AndroidRuntime(2052): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2585) 05-14 13:03:56.986: ERROR/AndroidRuntime(2052): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2679) 05-14 13:03:56.986: ERROR/AndroidRuntime(2052): at android.app.ActivityThread.access$2300(ActivityThread.java:125) 05-14 13:03:56.986: ERROR/AndroidRuntime(2052): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2033) 05-14 13:03:56.986: ERROR/AndroidRuntime(2052): at android.os.Handler.dispatchMessage(Handler.java:99) 05-14 13:03:56.986: ERROR/AndroidRuntime(2052): at android.os.Looper.loop(Looper.java:123) 05-14 13:03:56.986: ERROR/AndroidRuntime(2052): at android.app.ActivityThread.main(ActivityThread.java:4627) 05-14 13:03:56.986: ERROR/AndroidRuntime(2052): at java.lang.reflect.Method.invokeNative(Native Method) 05-14 13:03:56.986: ERROR/AndroidRuntime(2052): at java.lang.reflect.Method.invoke(Method.java:521) 05-14 13:03:56.986: ERROR/AndroidRuntime(2052): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:858) 05-14 13:03:56.986: ERROR/AndroidRuntime(2052): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616) 05-14 13:03:56.986: ERROR/AndroidRuntime(2052): at dalvik.system.NativeStart.main(Native Method) 05-14 13:03:56.986: ERROR/AndroidRuntime(2052): Caused by: java.lang.ClassNotFoundException: com.hanud.speedo.speedometer in loader dalvik.system.PathClassLoader[/data/app/com.hanud.speedo-2.apk] 05-14 13:03:56.986: ERROR/AndroidRuntime(2052): at dalvik.system.PathClassLoader.findClass(PathClassLoader.java:243) 05-14 13:03:56.986: ERROR/AndroidRuntime(2052): at java.lang.ClassLoader.loadClass(ClassLoader.java:573) 05-14 13:03:56.986: ERROR/AndroidRuntime(2052): at java.lang.ClassLoader.loadClass(ClassLoader.java:532) 05-14 13:03:56.986: ERROR/AndroidRuntime(2052): at android.app.Instrumentation.newActivity(Instrumentation.java:1021) 05-14 13:03:56.986: ERROR/AndroidRuntime(2052): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2577) 05-14 13:03:56.986: ERROR/AndroidRuntime(2052): ... 11 more 05-14 13:03:57.017: WARN/ActivityManager(91): Force finishing activity com.hanud.speedo/.speedometer 05-14 13:03:57.526: WARN/ActivityManager(91): Activity pause timeout for HistoryRecord{4382d820 com.hanud.speedo/.speedometer} 05-14 13:04:05.666: DEBUG/dalvikvm(1890): GC_EXPLICIT freed 4544 objects / 322792 bytes in 288ms 05-14 13:04:07.796: WARN/ActivityManager(91): Activity destroy timeout for HistoryRecord{4382d820 com.hanud.speedo/.speedometer} 05-14 13:04:12.016: INFO/ActivityManager(91): Start proc com.android.email for service com.android.email/.service.MailService: pid=2058 uid=10004 gids={3003, 1015}

and this is the code:

 import java.util.Date; import java.util.Timer; import java.util.TimerTask; import android.app.Activity; import android.content.Context; import android.hardware.Sensor; import android.hardware.SensorEvent; import android.hardware.SensorEventListener; import android.hardware.SensorManager; import android.os.Bundle; import android.os.Handler; import android.widget.TextView; public class Speedometer extends Activity { Handler handler = new Handler(); SensorManager sensorManager; TextView myTextView; float appliedAcceleration = 0; float currentAcceleration = 0; float velocity = 0; Date lastUpdate; @Override public void onCreate(Bundle icicle) { super.onCreate(icicle); setContentView(R.layout.main); myTextView = (TextView)findViewById(R.id.myTextView); lastUpdate = new Date(System.currentTimeMillis()); sensorManager = (SensorManager)getSystemService(Context.SENSOR_SERVICE); Sensor accelerometer = sensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER); sensorManager.registerListener(sensorEventListener, accelerometer, SensorManager.SENSOR_DELAY_FASTEST); Timer updateTimer = new Timer("velocityUpdate"); updateTimer.scheduleAtFixedRate(new TimerTask() { public void run() { updateGUI(); } }, 0, 1000); } private void updateGUI() { // Convert from meters per second to miles per hour. final double mph = (Math.round(100*velocity / 1.6 * 3.6))/100; // Update the GUI handler.post(new Runnable() { public void run() { myTextView.setText(String.valueOf(mph) + "mph"); } }); } private void updateVelocity() { // Calculate how long this acceleration has been applied. Date timeNow = new Date(System.currentTimeMillis()); long timeDelta = timeNow.getTime()-lastUpdate.getTime(); lastUpdate.setTime(timeNow.getTime()); // Calculate the change in velocity at the // current acceleration since the last update. float deltaVelocity = appliedAcceleration * (timeDelta/1000); appliedAcceleration = currentAcceleration; // Add the velocity change to the current velocity. velocity += deltaVelocity; } //private final SensorListener sensorListener = new SensorListener() { private final SensorEventListener sensorEventListener = new SensorEventListener() { double calibration = Double.NaN; public void onSensorChanged(SensorEvent event) { double x = event.values[0]; double y = event.values[1]; double z = event.values[2]; double a = Math.sqrt(Math.pow(x, 2) + Math.pow(y, 2) + Math.pow(z, 2)); if (calibration == Double.NaN) calibration = a; else { updateVelocity(); currentAcceleration = (float)a; } } public void onAccuracyChanged(Sensor sensor, int accuracy) { } }; }
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You have defined (probably in the android manifest) com.hanud.speedo.speedometer , and your name is Activity Speedometer (with capital S ).

To make this clear, change the name of the activity in the manifest file to Speedometer .

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