Android Sensors
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The document discusses Android sensors and how to access sensor data from an Android device. It describes the SensorManager class which provides access to sensors, and the SensorEventListener interface which listens for sensor value changes. It lists several sensor types available on Android like accelerometer, orientation, light, and magnetic field. It also covers sampling rates, accuracy levels, and provides an example of using the SensorManager to get accelerometer data. Finally, it introduces the Sensor Simulator tool which can simulate sensors for testing on an emulator.
Android Sensors
- 1. Android Sensors Jussi Pohjolainen
- 2. Overview • SensorManager: Access to sensors if hardware supports • SensorEventListener: Interface for class to listen sensor values as they change in =me
- 3. SensorManager • Access to device’s sensors • Reference by calling getSystemService • Disable sensors if you don’t need them! (drain baEery)
- 4. Sensor Type • Accelerometer, Orienta=on • Light • Magne=c field • Proximity • Temperature • …
- 5. Sampling Rate • How fast try to get the sensor data • Reques=ng specific sampling rate.. Hint to the system, no guarantees • SensorManager holds constant variables: – Fastest – Game – Normal – User Interface
- 6. Accuracy • How accurate is the informa=on? – High – Low – Medium – Unreliable • This is informa=on is sent to listener
- 7. SensorManager Example public class SensorActivity extends Activity implements SensorEventListener { private SensorManager mSensorManager; private Sensor mAccelerometer; 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.unregisteredListener(this); } public void onAccuracyChanged(Sensor sensor, int accuracy) { } public void onSensorChanged(SensorEvent event) { } }
- 8. Sensor Simulator • The current Android emulator does not support sensors • Use Sensor Simulator, open source project developed by Open Intents • Supports accelerometer, compass, orienta=on, and temperature sensors, • Download it from: – hEp://code.google.com/p/openintents/wiki/ SensorSimulator
- 9. Instruc=ons 1. Download the latest sensorsimulator- x.x.x.zip from the download tab and unzip. 2. Start bin/sensorsimulator-x.x.x.jar (Java standalone applica=on). 1. java –jar sensorsimulator-x.x.x.jar 3. Install bin/SensorSimulatorSettings- x.x.x.apk on your Android emulator. 4. Launch SensorSimulator on the emulator. 5. Enter IP address and socket (port) number into the emulator
- 10. 2. Start the Sensor Simulator Jar
- 11. 3. Install Sensor Simulator Apk
- 12. 4. Launch Sensor Simulator in Emulator
- 13. 5. Configure App
- 16. Using Sensor Simulator in Your App • Add external JAR lib/sensorsimulator- lib.x.x.x.jar to your project • Use sensorsimulator classes • Get reference to SensorManagerSimulator instead of SensorManager • Connect to simulator • Add permission to use internet
- 17. Add .jar to Project