I have a ball (bitmap) at the center of black surface View.
I want to move that ball to left of the screen, if we tilt the phone toward left.
Similarly for right side.
(Eg :- we control bike, in any bike racing android game).
Which sensor to use and how to gets its value.
The Code So Far......
public class ABC implements SensorEventListener {
public ABC(Context context){
sensormanager = (SensorManager) context
.getSystemService(Context.SENSOR_SERVICE);
sensor = sensormanager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
sensormanager.registerListener(this, sensor,
SensorManager.SENSOR_DELAY_GAME);
}
.
some Code
.
#Override
public void onAccuracyChanged(Sensor arg0, int arg1) {
}
#Override
public void onSensorChanged(SensorEvent arg0) {
}
}
You need to implement your code under onSensorChanged.
See example here:
#Override
public void onSensorChanged(SensorEvent arg0) {
float[] values = arg0.values;
// getting movement from x,y,z axis
float x = values[0];
float y = values[1];
float z = values[2];
}
Every time the sensor detects movement you get new values under the values[] array.
Now, you can use those values to do whatever you want.
It is good practice to register the listener under onResume() and unregister it under onPause(), like so:
#Override
protected void onResume() {
super.onResume();
// register the listener
sensorManager.registerListener(this,
sensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER),
SensorManager.SENSOR_DELAY_NORMAL);
}
#Override
protected void onPause() {
// unregister listener
super.onPause();
sensorManager.unregisterListener(this);
}
Hope this has helped.
You'll have to use the GYROSCOPE, not the ACCELEROMETER.
The Gyroscope tells you about the rotation around X, Y, Z axis.
Also have a look at the SensorManager.getRotationMatrix() method.
Related
If the user turns over the phone I want to react to that by stopping my text to speech reading. It would be a nice feature for my app, but how can I detect this motion? I'm not really familiar with motion sensors and I could not find this specific motion listener anywhere, mostly just screen orientations. Thanks for the help!
This sample activity demonstrates how a device's gravity sensor can be used to detect when the device is turned over. In method onSensorChanged(), term factor determines how complete the "turn over" must be. Typical range might be 0.7 to 0.95.
Support for Gravity Sensor was added in Android API 9. Not all devices have a gravity sensor.
public class MainActivity extends AppCompatActivity implements SensorEventListener {
private static final String TAG = "Demo";
private SensorManager mSensorManager;
private Sensor mGravitySensor;
private boolean mFacingDown;
#Override
public void onAccuracyChanged(Sensor sensor, int accuracy) {
// nothing
}
#Override
public void onSensorChanged(SensorEvent event) {
final float factor = 0.95F;
if (event.sensor == mGravitySensor) {
boolean nowDown = event.values[2] < -SensorManager.GRAVITY_EARTH * factor;
if (nowDown != mFacingDown) {
if (nowDown) {
Log.i(TAG, "DOWN");
} else {
Log.i(TAG, "UP");
}
mFacingDown = nowDown;
}
}
}
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mSensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE);
mGravitySensor = mSensorManager.getDefaultSensor(Sensor.TYPE_GRAVITY);
if (mGravitySensor == null) {
Log.w(TAG, "Device has no gravity sensor");
}
}
#Override
protected void onResume() {
super.onResume();
if (mGravitySensor != null) {
mSensorManager.registerListener(this, mGravitySensor, SensorManager.SENSOR_DELAY_NORMAL);
}
}
#Override
protected void onPause() {
super.onPause();
mSensorManager.unregisterListener(this);
}
}
I know that there are only two values of proximity : 0.0 & 1.0
I need a simple code to detect proximity through the device's sensors, and perform any task if proximity changes to 1.0
this is what i found.
public class SensorActivity extends Activity implements SensorEventListener {
private SensorManager mSensorManager;
private Sensor mSensor;
ImageView iv;
#Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.sensor_screen);
mSensorManager = (SensorManager) getSystemService(SENSOR_SERVICE);
mSensor = mSensorManager.getDefaultSensor(Sensor.TYPE_PROXIMITY);
iv = (ImageView) findViewById(R.id.imageView1);
}
protected void onResume() {
super.onResume();
mSensorManager.registerListener(this, mSensor,
SensorManager.SENSOR_DELAY_NORMAL);
}
protected void onPause() {
super.onPause();
mSensorManager.unregisterListener(this);
}
public void onAccuracyChanged(Sensor sensor, int accuracy) {
}
public void onSensorChanged(SensorEvent event) {
if (event.values[0] == 0) {
iv.setImageResource(R.drawable.near);
} else {
iv.setImageResource(R.drawable.far);
}
}
}
You can use the getMaximumRange() method to obtain your proximity sensor's max range and use it to determine what to do.
SensorManager sensorManager = (SensorManager)getSystemService(SENSOR_SERVICE);
Sensor proximitySensor = sensorManager.getDefaultSensor(Sensor.TYPE_PROXIMITY);
float maxRange = proximitySensor.getMaximumRange();
Now use maxRange to do what you want to do.
public void onSensorChanged(SensorEvent event) {
if(maxRange == event.values[0]) {
// Do something when something is far away.
}
else {
// Do something when something is near.
}
}
One very important thing. The proximity sensor varies from device to device. It not always reports 1.0 and 0.0. For example my Moto G (1st Gen.) reports 3 cm as its min range and 100 cm as its max range. So its best to obtain the max range of the device's sensor and use it in your code rather then hard-coding the value.
I am a java newer,
I want to get, for example, 10 different values of my phone's acceleration,
and get an average value from them.
But I can only find answers for continued data, or only one data.
Now I can get one data and display it on my screen.
Can I use for loop to calculate for 10 times?
Thank you.
public void onSensorChanged(SensorEvent event) {
// TODO Auto-generated method stub
aAngle = event.values[0];
bAngle = event.values[1];
}
private Button.OnClickListener listener = new Button.OnClickListener() {
switch(viewMode){
case VIEW_MODE_1:
title.setText(Double.toString(aAngle) + " " + Double.toString(bAngle));
break;}
I've tried to cast a for loop in the OnSensorChanged method, but it didn't work at all.
I tried to do this, but it seems to have a runtime error.
List<Sensor> sensors = sensorManager.getSensorList(Sensor.TYPE_ACCELEROMETER);
if (sensors.size() > 0 && sensors.size() <= 10) {
sensorManager.registerListener(this,sensors.get(count),SensorManager.SENSOR_DELAY_NORMAL);
count ++;
}
also, I create two list to save the result every time when my angle is changed.
for(int i = 0; i < aAngleList.size(); i++){
double aAngleTotal = 0;
double bAngleTotal = 0;
aAngleTotal += aAngleList.get(i);
bAngleTotal += bAngleList.get(i);
aAngleAverage = aAngleTotal / aAngleList.size();
bAngleAverage = bAngleTotal / bAngleList.size();
}
public void onSensorChanged(SensorEvent event) {
aAngleList.add(aAngle);
bAngleList.add(bAngle);
}
the for loop is in onResume, right under the if (sensors...)
onSensorChanged is fired everytime your sensor gets a new reading. you can place a counter for ten changes. keep track of values in a list,hashmap and aggregate them.
public class SensorActivity extends Activity, implements SensorEventListener {
private final SensorManager mSensorManager;
private final Sensor mAccelerometer;
private int count=0;
private List<String> eventX=new ArrayList<String>();
public SensorActivity() {
mSensorManager = (SensorManager)getSystemService(SENSOR_SERVICE);
mAccelerometer = mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
}
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) {
}
public void onSensorChanged(SensorEvent event) {
eventX.add(event.getValueMethodwhateverItis());
count++;
if (count=10){
//aggregate from list do anything you want.;
}
}
}
SO im trying to make a App that tracks which direction the phone is pointed VIA the compass and once a button is hit on the screen it displays the number of where it is pointed in degrees. So far i understand how the compass is created but can not find which values are the pointed direction in relation to North. Here is what i have so far.
public class compass extends Activity implements OnClickListener, SensorEventListener{
private final SensorManager DirPoint;
float var;
TextView theNumber;
Button DirectionIn;
public compass(){
DirPoint = (SensorManager) getSystemService(Context.SENSOR_SERVICE);
}
public void onAccuracyChanged(Sensor sensor, int accuracy) {}
public void onSensorChanged(SensorEvent event) {}
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
theNumber = (textView) findViewById(R.id.output);
DirectionIn =(Button) findViewById(R.Id.Buton);
DirectionIn.setOnClickListener(new OnClickListener(){
#Override
public void onClick(View v) {
//gets direction of phone compass
// ((TextView)findViewById(R.id.output)).setText(var);
}
}
}
}
Any help would be welcomed or if im headed in the right direction even would be nice.
You have to implement a "compass". You can do this like this:
Let your activity implement the SensorEventListener and add the necessary fields:
public class CompassActivity extends Activity implements SensorEventListener {
private SensorManager sensorManager;
private Sensor accelerometer;
private Sensor magnetometer;
private float[] lastAccelerometer = new float[3];
private float[] lastMagnetometer = new float[3];
private boolean lastAccelerometerSet = false;
private boolean lastMagnetometerSet = false;
private float[] rotationMatrix = new float[9];
private float[] orientation = new float[3];
private float currentDegree = 0f;
In the onCreate method of the activity get and start the two sensors, the accelerometer and the magnetometer:
// onCreate method stub ...
sensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE);
accelerometer = sensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
magnetometer = sensorManager.getDefaultSensor(Sensor.TYPE_MAGNETIC_FIELD);
sensorManager.registerListener(this, accelerometer, SensorManager.SENSOR_DELAY_UI);
sensorManager.registerListener(this, magnetometer, SensorManager.SENSOR_DELAY_UI);
// more onCreate method stub ....
In the method of the SensorEventListener you can now calculate the heading of the phone and calculate the bearing between the current location and a other location:
#Override
public void onSensorChanged(SensorEvent event) {
if (event.sensor == this.accelerometer) {
System.arraycopy(event.values, 0, this.lastAccelerometer, 0, event.values.length);
this.lastAccelerometerSet = true;
} else if (event.sensor == this.magnetometer) {
System.arraycopy(event.values, 0, this.lastMagnetometer, 0, event.values.length);
this.lastMagnetometerSet = true;
}
if (this.lastAccelerometerSet && this.lastAccelerometerSet) {
SensorManager.getRotationMatrix(this.rotationMatrix,null, this.lastAccelerometer, this.lastMagnetometer);
SensorManager.getOrientation(this.rotationMatrix, this.orientation);
float azimuthInRadiands = this.orientation[0];
// this is now the heading of the phone. If you want
// to rotate a view to north don´t forget that you have
// to rotate by the negative value.
float azimuthInDegrees = (float) Math.toDegrees(azimuthInRadiands);
}
}
But don´t forget that there is much more behind a compass. You have to show the user if the magnetic field sensor is uncalibrated. You have to calculate the difference between the magnetic and the geographic north...
I have created a small compass helper class. The HowTo is in the readme. It will provide you all the information you need to present a compass on the screen:
Compass Assistant on GitHub
It provides you the current heading of the device. Please don´t hesitate to ask me if you have problems.
For Details look here
Use a compination of TYPE_ACCELEROMETER and TYPE_MAGNETIC_FIELD.
Sensor beschleunigung = sensor.getSensorList(Sensor.TYPE_ACCELEROMETER).get(0);
Sensor magnetometer = sensor.getSensorList(Sensor.TYPE_MAGNETIC_FIELD).get(0);
sensor.registerListener(handler, beschleunigung, SensorManager.SENSOR_DELAY_NORMAL, null);
sensor.registerListener(handler, magnetometer, SensorManager.SENSOR_DELAY_NORMAL, null);
and
handler = new SensorEventListener() {
float[] mGravity;
float[] mGeomagnetic;
#Override
public void onSensorChanged( SensorEvent event ) {
if (event.sensor.getType() == Sensor.TYPE_ACCELEROMETER)
mGravity = event.values;
if (event.sensor.getType() == Sensor.TYPE_MAGNETIC_FIELD)
mGeomagnetic = event.values;
if (mGravity != null && mGeomagnetic != null) {
float R[] = new float[9];
float I[] = new float[9];
boolean success = SensorManager.getRotationMatrix(R, I, mGravity, mGeomagnetic);
if (success) {
float orientation[] = new float[3];
SensorManager.getOrientation(R, orientation);
azimut = orientation[0]; // orientation contains: azimut, pitch and roll
}
}
NavigationArrow.this.setOffsetFromNorth((float) Math.toDegrees(azimut));
}
#Override
public void onAccuracyChanged( Sensor sensor, int accuracy ) {
}
};
Hope that helps :)
I have the following class to read data from accelerometer:
public class Accelerometer implements SensorEventListener {
private SensorManager mSensorManager;
private Sensor mAccelerometer;
float deltaX;
float deltaY;
float deltaZ;
Activity activity;
public Accelerometer(Activity act)
{
this.activity = act;
mSensorManager = (SensorManager) this.activity.getSystemService(Context.SENSOR_SERVICE);
mAccelerometer = mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
mSensorManager.registerListener(this, mAccelerometer, SensorManager.SENSOR_DELAY_NORMAL);
}
public float getDeltaX()
{
return this.deltaX;
}
public float getDeltaY()
{
return this.deltaY;
}
public float getDeltaZ()
{
return this.deltaZ;
}
#Override
public void onSensorChanged(SensorEvent event) {
// TODO Auto-generated method stub
deltaX = event.values[0];
deltaY = event.values[1];
deltaZ = event.values[2];
}
}
and I am accessing this class from my main activity class using the following code:
Accelerometer sbt = new Accelerometer (this);
tvX.setText(Float.toString(sbt.getDeltaX()) + " " +Float.toString(sbt.getDeltaY()) + " "+Float.toString(sbt.getDeltaZ()));
However, it always shows me 0, 0, 0. not sure whats wrong with current code. any help would be highly appreciated.
THe accelerometer (and all sensor data) works on a callback system. It won't call you until the next time it reads the sensor, and it will continue to call your onSensorChanged until you unregister. But if you try to set the text immediately after registering, you won't have been called yet. You need to set the textView in onSensorChanged, when you're updated with new values.