I am trying to Learn How to detect shaking and tried to make App Detect Shaking
but onAccuryChange always on 3
#Override
public void onAccuracyChanged(Sensor sensor, int i) {
switch(i){
case 2:
txt.setText("Shaked");
break;
case 3:
txt.setText("Default");
break;
default:
txt.setText("Nothing");
break;
}
}
always show "Default"
The TextView Already Have Text="No Actions Yet"
The mobile on Table but it shows "Default" once it run
so why it only gives 3 and how can i make it detect shaking ?
this is the Declaration
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
txt=(TextView)findViewById(R.id.txt);
sensorManager=(SensorManager)getSystemService(SENSOR_SERVICE);
mAccelerometer=sensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
}
#Override
protected void onResume() {
super.onResume();
sensorManager.registerListener(this, mAccelerometer, SensorManager.SENSOR_DELAY_NORMAL);
}
#Override
protected void onPause() {
super.onPause();
sensorManager.unregisterListener(this);
}
Hello Follow with below steps:
Create interface with name "AccelerometerListener":
public interface AccelerometerListener {
public void onAccelerationChanged(float x, float y, float z);
public void onShake(float force);
}
Create Class name as "MainAccelerometer.java", it is main activity:
public class MainAccelerometer extends Activity implements AccelerometerListener{
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.accelerometer_example_main);
// Check onResume Method to start accelerometer listener
}
public void onAccelerationChanged(float x, float y, float z) {
// TODO Auto-generated method stub
}
public void onShake(float force) {
// Do your stuff here
// Called when Motion Detected
Toast.makeText(getBaseContext(), "Motion detected",
Toast.LENGTH_SHORT).show();
}
#Override
public void onResume() {
super.onResume();
Toast.makeText(getBaseContext(), "onResume Accelerometer Started",
Toast.LENGTH_SHORT).show();
//Check device supported Accelerometer senssor or not
if (AccelerometerManager.isSupported(this)) {
//Start Accelerometer Listening
AccelerometerManager.startListening(this);
}
}
#Override
public void onStop() {
super.onStop();
//Check device supported Accelerometer senssor or not
if (AccelerometerManager.isListening()) {
//Start Accelerometer Listening
AccelerometerManager.stopListening();
Toast.makeText(getBaseContext(), "onStop Accelerometer Stoped",
Toast.LENGTH_SHORT).show();
}
}
#Override
public void onDestroy() {
super.onDestroy();
Log.i("Sensor", "Service distroy");
//Check device supported Accelerometer senssor or not
if (AccelerometerManager.isListening()) {
//Start Accelerometer Listening
AccelerometerManager.stopListening();
Toast.makeText(getBaseContext(), "onDestroy Accelerometer Stoped",
Toast.LENGTH_SHORT).show();
}
}
}
Create Class name as "AccelerometerManager.java", which act as manager for managing accelerometer.
public class AccelerometerManager {
private static Context aContext=null;
/** Accuracy configuration */
private static float threshold = 15.0f;
private static int interval = 200;
private static Sensor sensor;
private static SensorManager sensorManager;
// you could use an OrientationListener array instead
// if you plans to use more than one listener
private static AccelerometerListener listener;
/** indicates whether or not Accelerometer Sensor is supported */
private static Boolean supported;
/** indicates whether or not Accelerometer Sensor is running */
private static boolean running = false;
/**
* Returns true if the manager is listening to orientation changes
*/
public static boolean isListening() {
return running;
}
/**
* Unregisters listeners
*/
public static void stopListening() {
running = false;
try {
if (sensorManager != null && sensorEventListener != null) {
sensorManager.unregisterListener(sensorEventListener);
}
} catch (Exception e) {}
}
/**
* Returns true if at least one Accelerometer sensor is available
*/
public static boolean isSupported(Context context) {
aContext = context;
if (supported == null) {
if (aContext != null) {
sensorManager = (SensorManager) aContext.
getSystemService(Context.SENSOR_SERVICE);
// Get all sensors in device
List<Sensor> sensors = sensorManager.getSensorList(
Sensor.TYPE_ACCELEROMETER);
supported = new Boolean(sensors.size() > 0);
} else {
supported = Boolean.FALSE;
}
}
return supported;
}
/**
* Configure the listener for shaking
* #param threshold
* minimum acceleration variation for considering shaking
* #param interval
* minimum interval between to shake events
*/
public static void configure(int threshold, int interval) {
AccelerometerManager.threshold = threshold;
AccelerometerManager.interval = interval;
}
/**
* Registers a listener and start listening
* #param accelerometerListener
* callback for accelerometer events
*/
public static void startListening( AccelerometerListener accelerometerListener )
{
sensorManager = (SensorManager) aContext.
getSystemService(Context.SENSOR_SERVICE);
// Take all sensors in device
List<Sensor> sensors = sensorManager.getSensorList(
Sensor.TYPE_ACCELEROMETER);
if (sensors.size() > 0) {
sensor = sensors.get(0);
// Register Accelerometer Listener
running = sensorManager.registerListener(
sensorEventListener, sensor,
SensorManager.SENSOR_DELAY_GAME);
listener = accelerometerListener;
}
}
/**
* Configures threshold and interval
* And registers a listener and start listening
* #param accelerometerListener
* callback for accelerometer events
* #param threshold
* minimum acceleration variation for considering shaking
* #param interval
* minimum interval between to shake events
*/
public static void startListening(
AccelerometerListener accelerometerListener,
int threshold, int interval) {
configure(threshold, interval);
startListening(accelerometerListener);
}
/**
* The listener that listen to events from the accelerometer listener
*/
private static SensorEventListener sensorEventListener =
new SensorEventListener() {
private long now = 0;
private long timeDiff = 0;
private long lastUpdate = 0;
private long lastShake = 0;
private float x = 0;
private float y = 0;
private float z = 0;
private float lastX = 0;
private float lastY = 0;
private float lastZ = 0;
private float force = 0;
public void onAccuracyChanged(Sensor sensor, int accuracy) {}
public void onSensorChanged(SensorEvent event) {
// use the event timestamp as reference
// so the manager precision won't depends
// on the AccelerometerListener implementation
// processing time
now = event.timestamp;
x = event.values[0];
y = event.values[1];
z = event.values[2];
// if not interesting in shake events
// just remove the whole if then else block
if (lastUpdate == 0) {
lastUpdate = now;
lastShake = now;
lastX = x;
lastY = y;
lastZ = z;
Toast.makeText(aContext,"No Motion detected",
Toast.LENGTH_SHORT).show();
} else {
timeDiff = now - lastUpdate;
if (timeDiff > 0) {
/*force = Math.abs(x + y + z - lastX - lastY - lastZ)
/ timeDiff;*/
force = Math.abs(x + y + z - lastX - lastY - lastZ);
if (Float.compare(force, threshold) >0 ) {
//Toast.makeText(Accelerometer.getContext(),
//(now-lastShake)+" >= "+interval, 1000).show();
if (now - lastShake >= interval) {
// trigger shake event
listener.onShake(force);
}
else
{
Toast.makeText(aContext,"No Motion detected",
Toast.LENGTH_SHORT).show();
}
lastShake = now;
}
lastX = x;
lastY = y;
lastZ = z;
lastUpdate = now;
}
else
{
Toast.makeText(aContext,"No Motion detected", Toast.LENGTH_SHORT).show();
}
}
// trigger change event
listener.onAccelerationChanged(x, y, z);
}
};
}
In Manifest, do a entry:
<uses-permission android:name="android.permission.READ_PHONE_STATE"></uses-permission>
Create layout file name as "accelerometer_example_main.xml":
<RelativeLayout xmlns:android="<a class="vglnk" href="http://schemas.android.com/apk/res/android" rel="nofollow"><span>http</span><span>://</span><span>schemas</span><span>.</span><span>android</span><span>.</span><span>com</span><span>/</span><span>apk</span><span>/</span><span>res</span><span>/</span><span>android</span></a>"
xmlns:tools="<a class="vglnk" href="http://schemas.android.com/tools" rel="nofollow"><span>http</span><span>://</span><span>schemas</span><span>.</span><span>android</span><span>.</span><span>com</span><span>/</span><span>tools</span></a>"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainAccelerometer" >
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true"
android:text="Shake / Tilt Your Phone To Get Accelerometer Motion Alerts" />
</RelativeLayout>
Happy Coding.
I am in the process of developing an Android music player which will do the the following actions once a shake action is detected. Actions: 1. Do Nothing 2. Play or Pause 3. Next Song 4. Previous Song
I have created a Service class for the shaking action and it is as follows.
public class Shaker extends Service implements SensorEventListener {
SharedPreferences sharedPreferences;
private static final int MIN_TIME_BETWEEN_SHAKES_MILLISECS = 1000;
private long mLastShakeTime;
private SensorManager sensorManager;
private static final String SHAKE_ACTION_PREFERENCE = "shake_action_preference";
private static final String SHAKE_THRESHOLD_PREFERENCE = "shake_threshold_preference";
#Override
public IBinder onBind(Intent intent) {
return null;
}
public void onCreate() {
sharedPreferences = PreferenceManager.getDefaultSharedPreferences(getApplicationContext());
super.onCreate();
}
public void onDestroy() {
super.onDestroy();
sensorManager.unregisterListener(this);
}
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
sensorManager = (SensorManager) getSystemService(SENSOR_SERVICE);
sensorManager.registerListener(this, sensorManager
.getDefaultSensor(Sensor.TYPE_ACCELEROMETER), SensorManager.SENSOR_DELAY_UI);
return START_STICKY;
}
public void onStart(Intent intent, int startId) {
sensorManager = (SensorManager) getSystemService(SENSOR_SERVICE);
sensorManager.registerListener(this, sensorManager
.getDefaultSensor(Sensor.TYPE_ACCELEROMETER), SensorManager.SENSOR_DELAY_UI);
}
#Override
public void onAccuracyChanged(Sensor sensor, int accuracy) {
}
#Override
public void onSensorChanged(SensorEvent event) {
if (event.sensor.getType() == Sensor.TYPE_ACCELEROMETER) {
long curTime = System.currentTimeMillis();
if ((curTime - mLastShakeTime) > MIN_TIME_BETWEEN_SHAKES_MILLISECS) {
float x = event.values[0];
float y = event.values[1];
float z = event.values[2];
double acceleration = Math.sqrt(Math.pow(x, 2) +
Math.pow(y, 2) +
Math.pow(z, 2)) - SensorManager.GRAVITY_EARTH;
Log.d("Acceleration", "Acceleration is " + acceleration + "m/s^2");
String threshold = sharedPreferences.getString(SHAKE_THRESHOLD_PREFERENCE, "medium");
float SHAKE_THRESHOLD;
if(threshold.equals("high"))
SHAKE_THRESHOLD = 40.5f;
else if(threshold.equals("low"))
SHAKE_THRESHOLD = 15.5f;
else
SHAKE_THRESHOLD = 25.5f;
if (acceleration > SHAKE_THRESHOLD) {
mLastShakeTime = curTime;
Log.d("Shake", "Shake, Rattle, and Roll");
String opt = sharedPreferences.getString(SHAKE_ACTION_PREFERENCE, "nothing");
Log.d("SharedPreference", opt);
Log.d("SharedPreference", threshold);
if(opt.equals("play")) {
MusicPlayer.playOrPause();
} else if(opt.equals("next")) {
MusicPlayer.next();
} else if(opt.equals("prev")) {
MusicPlayer.previous(getApplicationContext(), false);
}
}
}
}
}
}
But when I run the apk files in actual devices, the shaking function is working only on certain phones and not working for all the mobiles.
I have tried on different mobiles using same Android OS, but it is working in one and not working in the other.
I couldn't figure out why it is like this. Can anybody suggest a solution for this?
I had this problem. onSensorChanged method is called for any changes but in some devices, it is called more than once.It cause problem in logic of the code.
I solved this problem by adding a private static boolean variable. (It causes this method called once).Once this method executes,this variable becomes true.
#Override
public void onSensorChanged(SensorEvent event) {
if(!variable) {
variable=true;
...
...
variable=false;
}
}
I've implemented SensorEventListener in my MainActivity, and it works quite well, i'd even say most of the time very well.
But weirdly, sometimes it completely stops working, I need to shake it in every direction for 5-10 seconds and it's magically back on.
It seems to be after the phone as idle/asleep for a long time.
I did implemented the register/unregister on onResume/onPause.
Here is my code, mostly coming from stackoverflow:
SensorManager sensorManager;
private float accel; // acceleration apart from gravity
private float accelCurrent; // current acceleration including gravity
private float accelLast; // last acceleration including gravity
private static final float SHAKE_THRESHOLD = 12.f;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initSensor();
}
private void initSensor() {
sensorManager = (SensorManager) getSystemService(SENSOR_SERVICE);
registerSensor();
}
private void registerSensor() {
HandlerThread handlerThread = new HandlerThread(HANDLER_THREAD_NAME_SENSOR);
handlerThread.start();
Handler handler = new Handler(handlerThread.getLooper());
sensorManager.registerListener(this, sensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER), SensorManager.SENSOR_DELAY_NORMAL, handler);
accel = 0.00f;
accelCurrent = SensorManager.GRAVITY_EARTH;
accelLast = SensorManager.GRAVITY_EARTH;
}
#Override
protected void onPause() {
super.onPause();
sensorManager.unregisterListener(this);
}
#Override
protected void onResume() {
super.onResume();
registerSensor();
}
#Override
public void onSensorChanged(SensorEvent event) {
float x = event.values[0];
float y = event.values[1];
float z = event.values[2];
accelLast = accelCurrent;
accelCurrent = (float) Math.sqrt((double) (x*x + y*y + z*z));
float delta = accelCurrent - accelLast;
accel = accel * 0.9f + delta; // perform low-cut filter
//Log.d(TAG, ">>> ALL shake accel = "+ accel);
if (accel > SHAKE_THRESHOLD) {
Log.d(TAG, "shake accel = "+ accel);
runOnUiThread(new Runnable() {
#Override
public void run() {
// Do stuffs in the UI
}
});
}
}
#Override
public void onAccuracyChanged(Sensor sensor, int accuracy) {
// Nothing do to here
}
It was fixed by changing the sensor delay to SensorManager.SENSOR_DELAY_FASTEST;
The registration now looks like :
// Global
private static final String HANDLER_THREAD_NAME_SENSOR = "sensorThread";
// ...Registration
HandlerThread handlerThread = new HandlerThread(HANDLER_THREAD_NAME_SENSOR);
handlerThread.start();
Handler handler = new Handler(handlerThread.getLooper());
mSensorManager.registerListener(this,
mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER),
SensorManager.SENSOR_DELAY_FASTEST,
handler);
(Now it works perfectly)I am new to android development and I have written an showActivity to show my result data from another class. In that class I implement a sensorEventListener and get sensor data. But when I want to display data in my showActivity, I get nothing to show. All the data is 0(or false) and I dont know what's wrong with my code. It's much appreciated if you can give me some advise on how to fix it. Thanks a lot.
This is my showActivity:
public class MapShowActivity extends AppCompatActivity {
public SensorUse mySensorUse ;
private TextView myText;
private Button myButton;
private Timer timer = new Timer();
private int count = 0;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mySensorUse = new SensorUse(MapShowActivity.this);
setContentView(R.layout.activity_map_show);
myText = (TextView)findViewById(R.id.orientation);
}
public void startTimer(){
timer.scheduleAtFixedRate(detectNewOrientation, 100, 100);
}
TimerTask detectNewOrientation = new TimerTask(){
#Override
public void run() {
runOnUiThread(new Runnable() {
#Override
public void run() {
myText.setText(String.valueOf(mySensorUse.getOx()));
}
});
}
};
#Override
protected void onResume() {
super.onResume();
mySensorUse.sensorRegister(MapShowActivity.this);
startTimer();
}
#Override
protected void onPause() {
super.onPause();
mySensorUse.sensorUnregister();
}
}
And this is my Sensor class:
public class SensorUse implements SensorEventListener{
private float[] accValues = new float[3];
private float[] magValues = new float[3];
private float[] orientationValues = new float[4];
private float[] resultRotationMatrix = new float[16];
public float ax;
public float ay;
public float az;
public float sumAcc;
public float ox;
public static boolean flag = false;
public boolean rotationMatrixGenerated;
private SensorManager mySensorManager;
private Sensor accSencor, magSensor;
public SensorUse(Context context){
}
#Override
public void onSensorChanged(SensorEvent event) {
if (event.sensor.getType() == Sensor.TYPE_LINEAR_ACCELERATION){
accValues = event.values.clone();
ax = accValues[0];
ay = accValues[1];
az = accValues[2];
sumAcc = (float) Math.sqrt(ax*ax + ay*ay + az*az);
flag = true;
}
else if (event.sensor.getType() == Sensor.TYPE_MAGNETIC_FIELD){
magValues = event.values.clone();
}
if (accValues != null && magValues != null){
rotationMatrixGenerated = SensorManager.getRotationMatrix(resultRotationMatrix,
null, accValues, magValues);
if(rotationMatrixGenerated) {
SensorManager.getOrientation(resultRotationMatrix, orientationValues);
ox = (float) Math.toDegrees(orientationValues[0]);
}
}
}
#Override
public void onAccuracyChanged(Sensor sensor, int accuracy) {
}
public void sensorRegister(Context context){
mySensorManager = (SensorManager) context.getSystemService(Context.SENSOR_SERVICE);
accSencor = mySensorManager.getDefaultSensor(Sensor.TYPE_LINEAR_ACCELERATION);
magSensor = mySensorManager.getDefaultSensor(Sensor.TYPE_MAGNETIC_FIELD);
mySensorManager.registerListener(this, accSencor, SensorManager.SENSOR_DELAY_GAME);
mySensorManager.registerListener(this, magSensor, SensorManager.SENSOR_DELAY_GAME);
}
public void sensorUnregister(){
mySensorManager.unregisterListener(this, accSencor);
mySensorManager.unregisterListener(this, magSensor);
}
public float getAx(){
return ax;
}
public float getOx(){
return ox;
}
}
App doesn't know which class will be handling the sensor data.
You have to register your sensor class (SensorUse) object
to get accelerometer data.
Find example code below:
sensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE);
senAccelerometer = sensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
sensorManager.registerListener(mySensorUse, senAccelerometer , SensorManager.SENSOR_DELAY_NORMAL);
sensorManger is object of SensorManager
mySensorUse is class that has implemented SensorEventListener
I need to add a shake feature that will refresh my Android application.
All I find of documentation involves implementing the SensorListener, but Eclipse tells me it's deprecated and suggest SensorEventListener.
Anybody that has a nice guide to how I go about creating this shake controller?
Here is an example code.
Put this into your activity class:
/* put this into your activity class */
private SensorManager mSensorManager;
private float mAccel; // acceleration apart from gravity
private float mAccelCurrent; // current acceleration including gravity
private float mAccelLast; // last acceleration including gravity
private final SensorEventListener mSensorListener = new SensorEventListener() {
public void onSensorChanged(SensorEvent se) {
float x = se.values[0];
float y = se.values[1];
float z = se.values[2];
mAccelLast = mAccelCurrent;
mAccelCurrent = (float) Math.sqrt((double) (x*x + y*y + z*z));
float delta = mAccelCurrent - mAccelLast;
mAccel = mAccel * 0.9f + delta; // perform low-cut filter
}
public void onAccuracyChanged(Sensor sensor, int accuracy) {
}
};
#Override
protected void onResume() {
super.onResume();
mSensorManager.registerListener(mSensorListener, mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER), SensorManager.SENSOR_DELAY_NORMAL);
}
#Override
protected void onPause() {
mSensorManager.unregisterListener(mSensorListener);
super.onPause();
}
And add this to your onCreate method:
/* do this in onCreate */
mSensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE);
mSensorManager.registerListener(mSensorListener, mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER), SensorManager.SENSOR_DELAY_NORMAL);
mAccel = 0.00f;
mAccelCurrent = SensorManager.GRAVITY_EARTH;
mAccelLast = SensorManager.GRAVITY_EARTH;
You can then ask "mAccel" wherever you want in your application for the current acceleration, independent from the axis and cleaned from static acceleration such as gravity.
It will be approx. 0 if there is no movement, and, lets say >2 if the device is shaked.
Based on the comments - to test this:
if (mAccel > 12) {
Toast toast = Toast.makeText(getApplicationContext(), "Device has shaken.", Toast.LENGTH_LONG);
toast.show();
}
Notes:
The accelometer should be deactivated onPause and activated onResume to save resources (CPU, Battery).
The code assumes we are on planet Earth ;-) and initializes the acceleration to earth gravity. Otherwise you would get a strong "shake" when the application starts and "hits" the ground from free-fall. However, the code gets used to the gravitation due to the low-cut filter and would work also on other planets or in free space, once it is initialized.
(you never know how long your application will be in use...;-)
Here is my code for shake gesture detection:
import android.hardware.Sensor;
import android.hardware.SensorEvent;
import android.hardware.SensorEventListener;
import android.hardware.SensorManager;
/**
* Listener that detects shake gesture.
*/
public class ShakeEventListener implements SensorEventListener {
/** Minimum movement force to consider. */
private static final int MIN_FORCE = 10;
/**
* Minimum times in a shake gesture that the direction of movement needs to
* change.
*/
private static final int MIN_DIRECTION_CHANGE = 3;
/** Maximum pause between movements. */
private static final int MAX_PAUSE_BETHWEEN_DIRECTION_CHANGE = 200;
/** Maximum allowed time for shake gesture. */
private static final int MAX_TOTAL_DURATION_OF_SHAKE = 400;
/** Time when the gesture started. */
private long mFirstDirectionChangeTime = 0;
/** Time when the last movement started. */
private long mLastDirectionChangeTime;
/** How many movements are considered so far. */
private int mDirectionChangeCount = 0;
/** The last x position. */
private float lastX = 0;
/** The last y position. */
private float lastY = 0;
/** The last z position. */
private float lastZ = 0;
/** OnShakeListener that is called when shake is detected. */
private OnShakeListener mShakeListener;
/**
* Interface for shake gesture.
*/
public interface OnShakeListener {
/**
* Called when shake gesture is detected.
*/
void onShake();
}
public void setOnShakeListener(OnShakeListener listener) {
mShakeListener = listener;
}
#Override
public void onSensorChanged(SensorEvent se) {
// get sensor data
float x = se.values[SensorManager.DATA_X];
float y = se.values[SensorManager.DATA_Y];
float z = se.values[SensorManager.DATA_Z];
// calculate movement
float totalMovement = Math.abs(x + y + z - lastX - lastY - lastZ);
if (totalMovement > MIN_FORCE) {
// get time
long now = System.currentTimeMillis();
// store first movement time
if (mFirstDirectionChangeTime == 0) {
mFirstDirectionChangeTime = now;
mLastDirectionChangeTime = now;
}
// check if the last movement was not long ago
long lastChangeWasAgo = now - mLastDirectionChangeTime;
if (lastChangeWasAgo < MAX_PAUSE_BETHWEEN_DIRECTION_CHANGE) {
// store movement data
mLastDirectionChangeTime = now;
mDirectionChangeCount++;
// store last sensor data
lastX = x;
lastY = y;
lastZ = z;
// check how many movements are so far
if (mDirectionChangeCount >= MIN_DIRECTION_CHANGE) {
// check total duration
long totalDuration = now - mFirstDirectionChangeTime;
if (totalDuration < MAX_TOTAL_DURATION_OF_SHAKE) {
mShakeListener.onShake();
resetShakeParameters();
}
}
} else {
resetShakeParameters();
}
}
}
/**
* Resets the shake parameters to their default values.
*/
private void resetShakeParameters() {
mFirstDirectionChangeTime = 0;
mDirectionChangeCount = 0;
mLastDirectionChangeTime = 0;
lastX = 0;
lastY = 0;
lastZ = 0;
}
#Override
public void onAccuracyChanged(Sensor sensor, int accuracy) {
}
}
Add this in your activity:
private SensorManager mSensorManager;
private ShakeEventListener mSensorListener;
...
in onCreate() add:
mSensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE);
mSensorListener = new ShakeEventListener();
mSensorListener.setOnShakeListener(new ShakeEventListener.OnShakeListener() {
public void onShake() {
Toast.makeText(KPBActivityImpl.this, "Shake!", Toast.LENGTH_SHORT).show();
}
});
and:
#Override
protected void onResume() {
super.onResume();
mSensorManager.registerListener(mSensorListener,
mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER),
SensorManager.SENSOR_DELAY_UI);
}
#Override
protected void onPause() {
mSensorManager.unregisterListener(mSensorListener);
super.onPause();
}
Here's yet another implementation that builds on some of the tips in here as well as the code from the Android developer site.
MainActivity.java
public class MainActivity extends Activity {
private ShakeDetector mShakeDetector;
private SensorManager mSensorManager;
private Sensor mAccelerometer;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// ShakeDetector initialization
mSensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE);
mAccelerometer = mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
mShakeDetector = new ShakeDetector(new OnShakeListener() {
#Override
public void onShake() {
// Do stuff!
}
});
}
#Override
protected void onResume() {
super.onResume();
mSensorManager.registerListener(mShakeDetector, mAccelerometer, SensorManager.SENSOR_DELAY_UI);
}
#Override
protected void onPause() {
mSensorManager.unregisterListener(mShakeDetector);
super.onPause();
}
}
ShakeDetector.java
package com.example.test;
import android.hardware.Sensor;
import android.hardware.SensorEvent;
import android.hardware.SensorEventListener;
public class ShakeDetector implements SensorEventListener {
// Minimum acceleration needed to count as a shake movement
private static final int MIN_SHAKE_ACCELERATION = 5;
// Minimum number of movements to register a shake
private static final int MIN_MOVEMENTS = 2;
// Maximum time (in milliseconds) for the whole shake to occur
private static final int MAX_SHAKE_DURATION = 500;
// Arrays to store gravity and linear acceleration values
private float[] mGravity = { 0.0f, 0.0f, 0.0f };
private float[] mLinearAcceleration = { 0.0f, 0.0f, 0.0f };
// Indexes for x, y, and z values
private static final int X = 0;
private static final int Y = 1;
private static final int Z = 2;
// OnShakeListener that will be notified when the shake is detected
private OnShakeListener mShakeListener;
// Start time for the shake detection
long startTime = 0;
// Counter for shake movements
int moveCount = 0;
// Constructor that sets the shake listener
public ShakeDetector(OnShakeListener shakeListener) {
mShakeListener = shakeListener;
}
#Override
public void onSensorChanged(SensorEvent event) {
// This method will be called when the accelerometer detects a change.
// Call a helper method that wraps code from the Android developer site
setCurrentAcceleration(event);
// Get the max linear acceleration in any direction
float maxLinearAcceleration = getMaxCurrentLinearAcceleration();
// Check if the acceleration is greater than our minimum threshold
if (maxLinearAcceleration > MIN_SHAKE_ACCELERATION) {
long now = System.currentTimeMillis();
// Set the startTime if it was reset to zero
if (startTime == 0) {
startTime = now;
}
long elapsedTime = now - startTime;
// Check if we're still in the shake window we defined
if (elapsedTime > MAX_SHAKE_DURATION) {
// Too much time has passed. Start over!
resetShakeDetection();
}
else {
// Keep track of all the movements
moveCount++;
// Check if enough movements have been made to qualify as a shake
if (moveCount > MIN_MOVEMENTS) {
// It's a shake! Notify the listener.
mShakeListener.onShake();
// Reset for the next one!
resetShakeDetection();
}
}
}
}
#Override
public void onAccuracyChanged(Sensor sensor, int accuracy) {
// Intentionally blank
}
private void setCurrentAcceleration(SensorEvent event) {
/*
* BEGIN SECTION from Android developer site. This code accounts for
* gravity using a high-pass filter
*/
// alpha is calculated as t / (t + dT)
// with t, the low-pass filter's time-constant
// and dT, the event delivery rate
final float alpha = 0.8f;
// Gravity components of x, y, and z acceleration
mGravity[X] = alpha * mGravity[X] + (1 - alpha) * event.values[X];
mGravity[Y] = alpha * mGravity[Y] + (1 - alpha) * event.values[Y];
mGravity[Z] = alpha * mGravity[Z] + (1 - alpha) * event.values[Z];
// Linear acceleration along the x, y, and z axes (gravity effects removed)
mLinearAcceleration[X] = event.values[X] - mGravity[X];
mLinearAcceleration[Y] = event.values[Y] - mGravity[Y];
mLinearAcceleration[Z] = event.values[Z] - mGravity[Z];
/*
* END SECTION from Android developer site
*/
}
private float getMaxCurrentLinearAcceleration() {
// Start by setting the value to the x value
float maxLinearAcceleration = mLinearAcceleration[X];
// Check if the y value is greater
if (mLinearAcceleration[Y] > maxLinearAcceleration) {
maxLinearAcceleration = mLinearAcceleration[Y];
}
// Check if the z value is greater
if (mLinearAcceleration[Z] > maxLinearAcceleration) {
maxLinearAcceleration = mLinearAcceleration[Z];
}
// Return the greatest value
return maxLinearAcceleration;
}
private void resetShakeDetection() {
startTime = 0;
moveCount = 0;
}
// (I'd normally put this definition in it's own .java file)
public interface OnShakeListener {
public void onShake();
}
}
I really liked Peterdk's answer. I took it upon myself to make a coulpe of tweaks to his code .
file: ShakeDetector.java
import android.hardware.Sensor;
import android.hardware.SensorEvent;
import android.hardware.SensorEventListener;
import android.hardware.SensorManager;
import android.util.FloatMath;
public class ShakeDetector implements SensorEventListener {
// The gForce that is necessary to register as shake. Must be greater than 1G (one earth gravity unit)
private static final float SHAKE_THRESHOLD_GRAVITY = 2.7F;
private static final int SHAKE_SLOP_TIME_MS = 500;
private static final int SHAKE_COUNT_RESET_TIME_MS = 3000;
private OnShakeListener mListener;
private long mShakeTimestamp;
private int mShakeCount;
public void setOnShakeListener(OnShakeListener listener) {
this.mListener = listener;
}
public interface OnShakeListener {
public void onShake(int count);
}
#Override
public void onAccuracyChanged(Sensor sensor, int accuracy) {
// ignore
}
#Override
public void onSensorChanged(SensorEvent event) {
if (mListener != null) {
float x = event.values[0];
float y = event.values[1];
float z = event.values[2];
float gX = x / SensorManager.GRAVITY_EARTH;
float gY = y / SensorManager.GRAVITY_EARTH;
float gZ = z / SensorManager.GRAVITY_EARTH;
// gForce will be close to 1 when there is no movement.
float gForce = FloatMath.sqrt(gX * gX + gY * gY + gZ * gZ);
if (gForce > SHAKE_THRESHOLD_GRAVITY) {
final long now = System.currentTimeMillis();
// ignore shake events too close to each other (500ms)
if (mShakeTimestamp + SHAKE_SLOP_TIME_MS > now ) {
return;
}
// reset the shake count after 3 seconds of no shakes
if (mShakeTimestamp + SHAKE_COUNT_RESET_TIME_MS < now ) {
mShakeCount = 0;
}
mShakeTimestamp = now;
mShakeCount++;
mListener.onShake(mShakeCount);
}
}
}
}
Also, don't forget that you need to register an instance of the ShakeDetector with the SensorManager.
// ShakeDetector initialization
mSensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE);
mAccelerometer = mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
mShakeDetector = new ShakeDetector();
mShakeDetector.setOnShakeListener(new OnShakeListener() {
#Override
public void onShake(int count) {
handleShakeEvent(count);
}
});
mSensorManager.registerListener(mShakeDetector, mAccelerometer, SensorManager.SENSOR_DELAY_UI);
I am developing a motion-detection and shake-detection app for my university project.
Besides the original target of the application, I am splitting the library part (responsible for motion and shake detection) from the app. The code is free, available on SourceForge with the project name "BenderCatch". Documentation I am producing will be ready around mid-september.
http://sf.net/projects/bendercatch
It uses a more precise way to detect shake: watches BOTH the difference of force between SensorEvents AND the oscillations present in X and Y axis when you perform a shake. It can even make a sound (or vibrate) on each oscillation of the shake.
Feel free to ask me more by e-mail at raffaele [at] terzigno [dot] com
I have written a small example for detecting vertical and horizontal shakes and showing a Toast.
public class Accelerometerka2Activity extends Activity implements SensorEventListener {
private float mLastX, mLastY, mLastZ;
private boolean mInitialized;
private SensorManager mSensorManager;
private Sensor mAccelerometer;
private final float NOISE = (float) 8.0;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
mInitialized = false;
mSensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE);
mAccelerometer = mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
mSensorManager.registerListener(this, mAccelerometer , SensorManager.SENSOR_DELAY_NORMAL);
}
protected void onResume() {
super.onResume();
mSensorManager.registerListener(this, mAccelerometer, SensorManager.SENSOR_DELAY_NORMAL);
}
protected void onPause() {
super.onPause();
mSensorManager.unregisterListener(this);
}
public void onAccuracyChanged(Sensor sensor, int accuracy) {
// can be safely ignored for this demo
}
public void onSensorChanged(SensorEvent event) {
float x = event.values[0];
float y = event.values[1];
float z = event.values[2];
if (!mInitialized) {
mLastX = x;
mLastY = y;
mLastZ = z;
mInitialized = true;
} else {
float deltaX = Math.abs(mLastX - x);
float deltaY = Math.abs(mLastY - y);
float deltaZ = Math.abs(mLastZ - z);
if (deltaX < NOISE) deltaX = (float)0.0;
if (deltaY < NOISE) deltaY = (float)0.0;
if (deltaZ < NOISE) deltaZ = (float)0.0;
mLastX = x;
mLastY = y;
mLastZ = z;
if (deltaX > deltaY) {
Toast.makeText(getBaseContext(), "Horizental", Toast.LENGTH_SHORT).show();
} else if (deltaY > deltaX) {
Toast.makeText(getBaseContext(), "Vertical", Toast.LENGTH_SHORT).show();
}
}
}
}
You can use seismic. An example can be found here.
I have tried several implementations, but would like to share my own.
It uses G-force as unit for the threshold calculation. It makes it a bit easier to understand what is going on, and also with setting a good threshold.
It simply registers a increase in G force and triggers the listener if it exceeds the threshold. It doesn't use any direction thresholds, cause you don't really need that if you just want to register a good shake.
Of-course you need the standard registering and UN-registering of this listener in the Activity.
Also, to check what threshold you need, I recommend the following app (I am not in any way connected to that app)
public class UmitoShakeEventListener implements SensorEventListener {
/**
* The gforce that is necessary to register as shake. (Must include 1G
* gravity)
*/
private final float shakeThresholdInGForce = 2.25F;
private final float gravityEarth = SensorManager.GRAVITY_EARTH;
private OnShakeListener listener;
public void setOnShakeListener(OnShakeListener listener) {
this.listener = listener;
}
public interface OnShakeListener {
public void onShake();
}
#Override
public void onAccuracyChanged(Sensor sensor, int accuracy) {
// ignore
}
#Override
public void onSensorChanged(SensorEvent event) {
if (listener != null) {
float x = event.values[0];
float y = event.values[1];
float z = event.values[2];
float gX = x / gravityEarth;
float gY = y / gravityEarth;
float gZ = z / gravityEarth;
//G-Force will be 1 when there is no movement. (gravity)
float gForce = FloatMath.sqrt(gX * gX + gY * gY + gZ * gZ);
if (gForce > shakeThresholdInGForce) {
listener.onShake();
}
}
}
}
Here is another code for this:
import java.util.List;
import java.util.Timer;
import java.util.TimerTask;
import android.content.Context;
import android.hardware.Sensor;
import android.hardware.SensorEvent;
import android.hardware.SensorEventListener;
import android.hardware.SensorManager;
import android.os.Handler;
public class AccelerometerListener implements SensorEventListener {
private SensorManager sensorManager;
private List<Sensor> sensors;
private Sensor sensor;
private long lastUpdate = -1;
private long currentTime = -1;
private Main parent;
private Timer timer;
private int shakes;
private static final Handler mHandler = new Handler();
private float last_x, last_y, last_z;
private float current_x, current_y, current_z, currenForce;
private static final int FORCE_THRESHOLD = 500;
private final int DATA_X = SensorManager.DATA_X;
private final int DATA_Y = SensorManager.DATA_Y;
private final int DATA_Z = SensorManager.DATA_Z;
public AccelerometerListener(Main parent) {
SensorManager sensorService = (SensorManager) parent
.getSystemService(Context.SENSOR_SERVICE);
this.sensorManager = sensorService;
if (sensorService == null)
return;
this.sensors = sensorManager.getSensorList(Sensor.TYPE_ACCELEROMETER);
if (sensors.size() > 0) {
sensor = sensors.get(0);
}
this.parent = parent;
}
public void start() {
if (sensor == null)
return;
sensorManager.registerListener(this, sensor,
SensorManager.SENSOR_DELAY_GAME);
}
public void stop() {
if (sensorManager == null)
return;
sensorManager.unregisterListener(this);
}
public void onAccuracyChanged(Sensor s, int valu) {
}
public void onSensorChanged(SensorEvent event) {
if (event.sensor.getType() != Sensor.TYPE_ACCELEROMETER)
return;
currentTime = System.currentTimeMillis();
if ((currentTime - lastUpdate) > 50) {
long diffTime = (currentTime - lastUpdate);
lastUpdate = currentTime;
current_x = event.values[DATA_X];
current_y = event.values[DATA_Y];
current_z = event.values[DATA_Z];
currenForce = Math.abs(current_x + current_y + current_z - last_x
- last_y - last_z)
/ diffTime * 10000;
if (currenForce > FORCE_THRESHOLD) {
shakeDetected();
}
last_x = current_x;
last_y = current_y;
last_z = current_z;
}
}
private void shakeDetected() {
shakes++;
if (shakes == 1) {
if (timer != null) {
timer.cancel();
}
timer = new Timer();
timer.schedule(new TimerTask() {
#Override
public void run() {
if (shakes > 3) {
mHandler.post(new Runnable() {
public void run() {
// shake
}
});
}
shakes = 0;
}
}, 500);
}
}
}
package anywheresoftware.b4a.student;
import android.hardware.Sensor;
import android.hardware.SensorEvent;
import android.hardware.SensorEventListener;
import android.hardware.SensorManager;
import android.util.FloatMath;
public class ShakeEventListener implements SensorEventListener {
/*
* The gForce that is necessary to register as shake.
* Must be greater than 1G (one earth gravity unit).
* You can install "G-Force", by Blake La Pierre
* from the Google Play Store and run it to see how
* many G's it takes to register a shake
*/
private static final float SHAKE_THRESHOLD_GRAVITY = 2.7F;
private static int SHAKE_SLOP_TIME_MS = 500;
private static final int SHAKE_COUNT_RESET_TIME_MS = 1000;
private OnShakeListener mListener;
private long mShakeTimestamp;
private int mShakeCount;
public void setOnShakeListener(OnShakeListener listener) {
this.mListener = listener;
}
public interface OnShakeListener {
public void onShake(int count);
}
#Override
public void onAccuracyChanged(Sensor sensor, int accuracy) {
// ignore
}
#Override
public void onSensorChanged(SensorEvent event) {
if (mListener != null) {
float x = event.values[0];
float y = event.values[1];
float z = event.values[2];
float gX = x / SensorManager.GRAVITY_EARTH;
float gY = y / SensorManager.GRAVITY_EARTH;
float gZ = z / SensorManager.GRAVITY_EARTH;
// gForce will be close to 1 when there is no movement.
float gForce = FloatMath.sqrt(gX * gX + gY * gY + gZ * gZ);
if (gForce > SHAKE_THRESHOLD_GRAVITY) {
final long now = System.currentTimeMillis();
// ignore shake events too close to each other (500ms)
if (mShakeTimestamp + getSHAKE_SLOP_TIME_MS() > now) {
return;
}
// reset the shake count after 3 seconds of no shakes
if (mShakeTimestamp + SHAKE_COUNT_RESET_TIME_MS < now) {
mShakeCount = 0;
}
mShakeTimestamp = now;
mShakeCount++;
mListener.onShake(mShakeCount);
}
}
}
private long getSHAKE_SLOP_TIME_MS() {
// TODO Auto-generated method stub
return SHAKE_SLOP_TIME_MS;
}
public void setSHAKE_SLOP_TIME_MS(int sHAKE_SLOP_TIME_MS) {
SHAKE_SLOP_TIME_MS = sHAKE_SLOP_TIME_MS;
}
}
package com.example.shakingapp;
import android.app.Activity;
import android.graphics.Color;
import android.hardware.Sensor;
import android.hardware.SensorEvent;
import android.hardware.SensorEventListener;
import android.hardware.SensorManager;
import android.os.Bundle;
import android.view.View;
import android.view.Window;
import android.view.WindowManager;
import android.widget.Toast;
public class MainActivity extends Activity implements SensorEventListener {
private SensorManager sensorManager;
private boolean color = false;
private View view;
private long lastUpdate;
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
requestWindowFeature(Window.FEATURE_NO_TITLE);
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
WindowManager.LayoutParams.FLAG_FULLSCREEN);
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
view = findViewById(R.id.textView);
view.setBackgroundColor(Color.GREEN);
sensorManager = (SensorManager) getSystemService(SENSOR_SERVICE);
lastUpdate = System.currentTimeMillis();
}
#Override
public void onSensorChanged(SensorEvent event) {
if (event.sensor.getType() == Sensor.TYPE_ACCELEROMETER) {
getAccelerometer(event);
}
}
private void getAccelerometer(SensorEvent event) {
float[] values = event.values;
// Movement
float x = values[0];
float y = values[1];
float z = values[2];
System.out.println(x);
System.out.println(y);
System.out.println(z);
System.out.println(SensorManager.GRAVITY_EARTH );
float accelationSquareRoot = (x * x + y * y + z * z)
/ (SensorManager.GRAVITY_EARTH * SensorManager.GRAVITY_EARTH);
long actualTime = System.currentTimeMillis();
if (accelationSquareRoot >= 2) //
{
if (actualTime - lastUpdate < 200) {
return;
}
lastUpdate = actualTime;
Toast.makeText(this, "Device was shuffed "+accelationSquareRoot, Toast.LENGTH_SHORT)
.show();
if (color) {
view.setBackgroundColor(Color.GREEN);
} else {
view.setBackgroundColor(Color.RED);
}
color = !color;
}
}
#Override
public void onAccuracyChanged(Sensor sensor, int accuracy) {
}
#Override
protected void onResume() {
super.onResume();
// register this class as a listener for the orientation and
// accelerometer sensors
sensorManager.registerListener(this,
sensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER),
SensorManager.SENSOR_DELAY_NORMAL);
}
#Override
protected void onPause() {
// unregister listener
super.onPause();
sensorManager.unregisterListener(this);
}
}
Shaker.java
import java.util.ArrayList;
import android.content.Context;
import android.hardware.Sensor;
import android.hardware.SensorEvent;
import android.hardware.SensorEventListener;
import android.hardware.SensorManager;
public class Shaker implements SensorEventListener{
private static final String SENSOR_SERVICE = Context.SENSOR_SERVICE;
private SensorManager sensorMgr;
private Sensor mAccelerometer;
private boolean accelSupported;
private long timeInMillis;
private long threshold;
private OnShakerTreshold listener;
ArrayList<Float> valueStack;
public Shaker(Context context, OnShakerTreshold listener, long timeInMillis, long threshold) {
try {
this.timeInMillis = timeInMillis;
this.threshold = threshold;
this.listener = listener;
if (timeInMillis<100){
throw new Exception("timeInMillis < 100ms");
}
valueStack = new ArrayList<Float>((int)(timeInMillis/100));
sensorMgr = (SensorManager) context.getSystemService(SENSOR_SERVICE);
mAccelerometer = sensorMgr.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
} catch (Exception e){
e.printStackTrace();
}
}
public void start() {
try {
accelSupported = sensorMgr.registerListener(this, mAccelerometer, SensorManager.SENSOR_DELAY_GAME);
if (!accelSupported) {
stop();
throw new Exception("Sensor is not supported");
}
} catch (Exception e){
e.printStackTrace();
}
}
public void stop(){
try {
sensorMgr.unregisterListener(this, mAccelerometer);
} catch (Exception e){
e.printStackTrace();
}
}
#Override
protected void finalize() throws Throwable {
try {
stop();
} catch (Exception e){
e.printStackTrace();
}
super.finalize();
}
long lastUpdate = 0;
private float last_x;
private float last_y;
private float last_z;
public void onSensorChanged(SensorEvent event) {
try {
if (event.sensor == mAccelerometer) {
long curTime = System.currentTimeMillis();
if ((curTime-lastUpdate)>getNumberOfMeasures()){
lastUpdate = System.currentTimeMillis();
float[] values = event.values;
if (valueStack.size()>(int)getNumberOfMeasures())
valueStack.remove(0);
float x = (int)(values[SensorManager.DATA_X]);
float y = (int)(values[SensorManager.DATA_Y]);
float z = (int)(values[SensorManager.DATA_Z]);
float speed = Math.abs((x+y+z) - (last_x + last_y + last_z));
valueStack.add(speed);
String posText = String.format("X:%4.0f Y:%4.0f Z:%4.0f", (x-last_x), (y-last_y), (z-last_z));
last_x = (x);
last_y = (y);
last_z = (z);
float sumOfValues = 0;
float avgOfValues = 0;
for (float f : valueStack){
sumOfValues = (sumOfValues+f);
}
avgOfValues = sumOfValues/(int)getNumberOfMeasures();
if (avgOfValues>=threshold){
listener.onTreshold();
valueStack.clear();
}
System.out.println(String.format("M: %+4d A: %5.0f V: %4.0f %s", valueStack.size(),avgOfValues,speed,posText));
}
}
} catch (Exception e){
e.printStackTrace();
}
}
private long getNumberOfMeasures() {
return timeInMillis/100;
}
public void onAccuracyChanged(Sensor sensor, int accuracy) {}
public interface OnShakerTreshold {
public void onTreshold();
}
}
MainActivity.java
public class MainActivity extends Activity implements OnShakerTreshold{
private Shaker s;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
s = new Shaker(getApplicationContext(), this, 5000, 20);
// 5000 = 5 second of shaking
// 20 = minimal threshold (very angry shaking :D)
// beware screen rotation reset counter
}
#Override
protected void onResume() {
s.start();
super.onResume();
}
#Override
protected void onPause() {
s.stop();
super.onPause();
}
public void onTreshold() {
System.out.println("FIRE LISTENER");
RingtoneManager.getRingtone(getApplicationContext(), RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION)).play();
}
}
Have fun.
// Need to implement SensorListener
public class ShakeActivity extends Activity implements SensorListener {
// For shake motion detection.
private SensorManager sensorMgr;
private long lastUpdate = -1;
private float x, y, z;
private float last_x, last_y, last_z;
private static final int SHAKE_THRESHOLD = 800;
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// start motion detection
sensorMgr = (SensorManager) getSystemService(SENSOR_SERVICE);
boolean accelSupported = sensorMgr.registerListener(this,
SensorManager.SENSOR_ACCELEROMETER,
SensorManager.SENSOR_DELAY_GAME);
if (!accelSupported) {
// on accelerometer on this device
sensorMgr.unregisterListener(this,
SensorManager.SENSOR_ACCELEROMETER);
}
}
protected void onPause() {
if (sensorMgr != null) {
sensorMgr.unregisterListener(this,
SensorManager.SENSOR_ACCELEROMETER);
sensorMgr = null;
}
super.onPause();
}
public void onAccuracyChanged(int arg0, int arg1) {
// TODO Auto-generated method stub
}
public void onSensorChanged(int sensor, float[] values) {
if (sensor == SensorManager.SENSOR_ACCELEROMETER) {
long curTime = System.currentTimeMillis();
// only allow one update every 100ms.
if ((curTime - lastUpdate)> 100) {
long diffTime = (curTime - lastUpdate);
lastUpdate = curTime;
x = values[SensorManager.DATA_X];
y = values[SensorManager.DATA_Y];
z = values[SensorManager.DATA_Z];
float speed = Math.abs(x+y+z - last_x - last_y - last_z)
/ diffTime * 10000;
if (speed > SHAKE_THRESHOLD) {
// yes, this is a shake action! Do something about it!
}
last_x = x;
last_y = y;
last_z = z;
}
}
}
}
You should subscribe as a SensorEventListener, and get the accelerometer data.
Once you have it, you should monitor for sudden change in direction (sign) of acceleration on a certain axis. It would be a good indication for the 'shake' movement of device.
Working with me v.good
Reference
public class ShakeEventListener implements SensorEventListener {
public final static int SHAKE_LIMIT = 15;
public final static int LITTLE_SHAKE_LIMIT = 5;
private SensorManager mSensorManager;
private float mAccel = 0.00f;
private float mAccelCurrent = SensorManager.GRAVITY_EARTH;
private float mAccelLast = SensorManager.GRAVITY_EARTH;
private ShakeListener listener;
public interface ShakeListener {
public void onShake();
public void onLittleShake();
}
public ShakeEventListener(ShakeListener l) {
Activity a = (Activity) l;
mSensorManager = (SensorManager) a.getSystemService(Context.SENSOR_SERVICE);
listener = l;
registerListener();
}
public ShakeEventListener(Activity a, ShakeListener l) {
mSensorManager = (SensorManager) a.getSystemService(Context.SENSOR_SERVICE);
listener = l;
registerListener();
}
public void registerListener() {
mSensorManager.registerListener(this, mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER), SensorManager.SENSOR_DELAY_NORMAL);
}
public void unregisterListener() {
mSensorManager.unregisterListener(this);
}
public void onSensorChanged(SensorEvent se) {
float x = se.values[0];
float y = se.values[1];
float z = se.values[2];
mAccelLast = mAccelCurrent;
mAccelCurrent = (float) FloatMath.sqrt(x*x + y*y + z*z);
float delta = mAccelCurrent - mAccelLast;
mAccel = mAccel * 0.9f + delta;
if(mAccel > SHAKE_LIMIT)
listener.onShake();
else if(mAccel > LITTLE_SHAKE_LIMIT)
listener.onLittleShake();
}
public void onAccuracyChanged(Sensor sensor, int accuracy) {}
}
You might want to try open source tinybus. With it shake detection is as easy as this.
public class MainActivity extends Activity {
private Bus mBus;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
...
// Create a bus and attach it to activity
mBus = TinyBus.from(this).wire(new ShakeEventWire());
}
#Subscribe
public void onShakeEvent(ShakeEvent event) {
Toast.makeText(this, "Device has been shaken",
Toast.LENGTH_SHORT).show();
}
#Override
protected void onStart() {
super.onStart();
mBus.register(this);
}
#Override
protected void onStop() {
mBus.unregister(this);
super.onStop();
}
}
It uses seismic for shake detection.
I modify #peceps's answer and make kotlin version of it. And I also add LifecycleOwner parameter to make it lifecycle-aware.
import android.hardware.Sensor
import android.hardware.SensorEvent
import android.hardware.SensorEventListener
import android.hardware.SensorManager
import androidx.lifecycle.DefaultLifecycleObserver
import androidx.lifecycle.LifecycleOwner
import kotlin.math.abs
/**
* Listener that detects shake gesture.
*/
class ShakeEventListener(
lifecycleOwner: LifecycleOwner,
private val sensorManager: SensorManager,
private val onShake: () -> Unit = {}
) : SensorEventListener, DefaultLifecycleObserver {
/** Time when the gesture started. */
private var mFirstDirectionChangeTime: Long = 0
/** Time when the last movement started. */
private var mLastDirectionChangeTime: Long = 0
/** How many movements are considered so far. */
private var mDirectionChangeCount = 0
/** The last x position. */
private var lastX = 0f
/** The last y position. */
private var lastY = 0f
/** The last z position. */
private var lastZ = 0f
init {
sensorManager.registerListener(
this,
sensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER),
SensorManager.SENSOR_DELAY_UI
)
// observe lifecycle state
lifecycleOwner.lifecycle.addObserver(this)
}
override fun onResume(owner: LifecycleOwner) {
sensorManager.registerListener(
this,
sensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER),
SensorManager.SENSOR_DELAY_UI
)
}
override fun onPause(owner: LifecycleOwner) {
sensorManager.unregisterListener(this)
}
override fun onSensorChanged(se: SensorEvent) {
// get sensor data
val x = se.values[0]
val y = se.values[1]
val z = se.values[2]
// calculate movement
val totalMovement = abs(x + y + z - lastX - lastY - lastZ)
if (totalMovement > MIN_FORCE) {
// get time
val now = System.currentTimeMillis()
// store first movement time
if (mFirstDirectionChangeTime == 0L) {
mFirstDirectionChangeTime = now
mLastDirectionChangeTime = now
}
// check if the last movement was not long ago
val lastChangeWasAgo = now - mLastDirectionChangeTime
if (lastChangeWasAgo < MAX_PAUSE_BETWEEN_DIRECTION_CHANGE) {
// store movement data
mLastDirectionChangeTime = now
mDirectionChangeCount++
// store last sensor data
lastX = x
lastY = y
lastZ = z
// check how many movements are so far
if (mDirectionChangeCount >= MIN_DIRECTION_CHANGE) {
// check total duration
val totalDuration = now - mFirstDirectionChangeTime
if (totalDuration < MAX_TOTAL_DURATION_OF_SHAKE) {
onShake()
resetShakeParameters()
}
}
} else {
resetShakeParameters()
}
}
}
/**
* Resets the shake parameters to their default values.
*/
private fun resetShakeParameters() {
mFirstDirectionChangeTime = 0
mDirectionChangeCount = 0
mLastDirectionChangeTime = 0
lastX = 0f
lastY = 0f
lastZ = 0f
}
override fun onAccuracyChanged(sensor: Sensor, accuracy: Int) {}
companion object {
/** Minimum movement force to consider. */
private const val MIN_FORCE = 10
/**
* Minimum times in a shake gesture that the direction of movement needs to
* change.
*/
private const val MIN_DIRECTION_CHANGE = 3
/** Maximum pause between movements. */
private const val MAX_PAUSE_BETWEEN_DIRECTION_CHANGE = 200
/** Maximum allowed time for shake gesture. */
private const val MAX_TOTAL_DURATION_OF_SHAKE = 400
}
}
In your activity, add this code to make it detecting shake event:
ShakeEventListener(this, sensorManager){
// onShake logic
}