src/android/AccelListener.java - cordova-plugin-device-motion - Git at Google

 /*
        Licensed to the Apache Software Foundation (ASF) under one
        or more contributor license agreements.  See the NOTICE file
        distributed with this work for additional information
        regarding copyright ownership.  The ASF licenses this file
        to you under the Apache License, Version 2.0 (the
        "License"); you may not use this file except in compliance
        with the License.  You may obtain a copy of the License at

          http://www.apache.org/licenses/LICENSE-2.0

        Unless required by applicable law or agreed to in writing,
        software distributed under the License is distributed on an
        "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
        KIND, either express or implied.  See the License for the
        specific language governing permissions and limitations
        under the License.
 */
 package org.apache.cordova.devicemotion;

 import java.util.List;

 import org.apache.cordova.CordovaWebView;
 import org.apache.cordova.CallbackContext;
 import org.apache.cordova.CordovaInterface;
 import org.apache.cordova.CordovaPlugin;
 import org.apache.cordova.PluginResult;
 import org.json.JSONArray;
 import org.json.JSONException;
 import org.json.JSONObject;

 import android.content.Context;
 import android.hardware.Sensor;
 import android.hardware.SensorEvent;
 import android.hardware.SensorEventListener;
 import android.hardware.SensorManager;

 import android.os.Handler;
 import android.os.Looper;

 /**
  * This class listens to the accelerometer sensor and stores the latest
  * acceleration values x,y,z.
  */
 public class AccelListener extends CordovaPlugin implements SensorEventListener {

     public static int STOPPED = 0;
     public static int STARTING = 1;
     public static int RUNNING = 2;
     public static int ERROR_FAILED_TO_START = 3;

     private float x,y,z;                                // most recent acceleration values
     private long timestamp;                         // time of most recent value
     private int status;                                 // status of listener
     private int accuracy = SensorManager.SENSOR_STATUS_ACCURACY_MEDIUM;

     private SensorManager sensorManager;    // Sensor manager
     private Sensor mSensor;                           // Acceleration sensor returned by sensor manager

     private CallbackContext callbackContext;              // Keeps track of the JS callback context.

     private Handler mainHandler=null;
     private Runnable mainRunnable =new Runnable() {
         public void run() {
             AccelListener.this.timeout();
         }
     };

     /**
      * Create an accelerometer listener.
      */
     public AccelListener() {
         this.x = 0;
         this.y = 0;
         this.z = 0;
         this.timestamp = 0;
         this.setStatus(AccelListener.STOPPED);
      }

     /**
      * Sets the context of the Command. This can then be used to do things like
      * get file paths associated with the Activity.
      *
      * @param cordova The context of the main Activity.
      * @param webView The associated CordovaWebView.
      */
     @Override
     public void initialize(CordovaInterface cordova, CordovaWebView webView) {
         super.initialize(cordova, webView);
         this.sensorManager = (SensorManager) cordova.getActivity().getSystemService(Context.SENSOR_SERVICE);
     }

     /**
      * Executes the request.
      *
      * @param action        The action to execute.
      * @param args          The exec() arguments.
      * @param callbackId    The callback id used when calling back into JavaScript.
      * @return              Whether the action was valid.
      */
     public boolean execute(String action, JSONArray args, CallbackContext callbackContext) {
         if (action.equals("start")) {
             this.callbackContext = callbackContext;
             if (this.status != AccelListener.RUNNING) {
                 // If not running, then this is an async call, so don't worry about waiting
                 // We drop the callback onto our stack, call start, and let start and the sensor callback fire off the callback down the road
                 this.start();
             }
         }
         else if (action.equals("stop")) {
             if (this.status == AccelListener.RUNNING) {
                 this.stop();
             }
         } else {
           // Unsupported action
             return false;
         }

         PluginResult result = new PluginResult(PluginResult.Status.NO_RESULT, "");
         result.setKeepCallback(true);
         callbackContext.sendPluginResult(result);
         return true;
     }

     /**
      * Called by AccelBroker when listener is to be shut down.
      * Stop listener.
      */
     public void onDestroy() {
         this.stop();
     }

     //--------------------------------------------------------------------------
     // LOCAL METHODS
     //--------------------------------------------------------------------------
     //
     /**
      * Start listening for acceleration sensor.
      *
      * @return          status of listener
     */
     private int start() {
         // If already starting or running, then restart timeout and return
         if ((this.status == AccelListener.RUNNING) || (this.status == AccelListener.STARTING)) {
             startTimeout();
             return this.status;
         }

         this.setStatus(AccelListener.STARTING);

         // Get accelerometer from sensor manager
         List<Sensor> list = this.sensorManager.getSensorList(Sensor.TYPE_ACCELEROMETER);

         // If found, then register as listener
         if ((list != null) && (list.size() > 0)) {
           this.mSensor = list.get(0);
           if (this.sensorManager.registerListener(this, this.mSensor, SensorManager.SENSOR_DELAY_UI)) {
               this.setStatus(AccelListener.STARTING);
           } else {
               this.setStatus(AccelListener.ERROR_FAILED_TO_START);
               this.fail(AccelListener.ERROR_FAILED_TO_START, "Device sensor returned an error.");
               return this.status;
           };

         } else {
           this.setStatus(AccelListener.ERROR_FAILED_TO_START);
           this.fail(AccelListener.ERROR_FAILED_TO_START, "No sensors found to register accelerometer listening to.");
           return this.status;
         }

         startTimeout();

         return this.status;
     }
     private void startTimeout() {
         // Set a timeout callback on the main thread.
         stopTimeout();
         mainHandler = new Handler(Looper.getMainLooper());
         mainHandler.postDelayed(mainRunnable, 2000);
     }
     private void stopTimeout() {
         if(mainHandler!=null){
             mainHandler.removeCallbacks(mainRunnable);
         }
     }
     /**
      * Stop listening to acceleration sensor.
      */
     private void stop() {
         stopTimeout();
         if (this.status != AccelListener.STOPPED) {
             this.sensorManager.unregisterListener(this);
         }
         this.setStatus(AccelListener.STOPPED);
         this.accuracy = SensorManager.SENSOR_STATUS_UNRELIABLE;
     }

     /**
      * Returns latest cached position if the sensor hasn't returned newer value.
      *
      * Called two seconds after starting the listener.
      */
     private void timeout() {
         if (this.status == AccelListener.STARTING) {
             // call win with latest cached position
             this.timestamp = System.currentTimeMillis();
             this.win();
         }
     }

     /**
      * Called when the accuracy of the sensor has changed.
      *
      * @param sensor
      * @param accuracy
      */
     public void onAccuracyChanged(Sensor sensor, int accuracy) {
         // Only look at accelerometer events
         if (sensor.getType() != Sensor.TYPE_ACCELEROMETER) {
             return;
         }

         // If not running, then just return
         if (this.status == AccelListener.STOPPED) {
             return;
         }
         this.accuracy = accuracy;
     }

     /**
      * Sensor listener event.
      *
      * @param SensorEvent event
      */
     public void onSensorChanged(SensorEvent event) {
         // Only look at accelerometer events
         if (event.sensor.getType() != Sensor.TYPE_ACCELEROMETER) {
             return;
         }

         // If not running, then just return
         if (this.status == AccelListener.STOPPED) {
             return;
         }
         this.setStatus(AccelListener.RUNNING);

         if (this.accuracy >= SensorManager.SENSOR_STATUS_ACCURACY_MEDIUM) {

             // Save time that event was received
             this.timestamp = System.currentTimeMillis();
             this.x = event.values[0];
             this.y = event.values[1];
             this.z = event.values[2];

             this.win();
         }
     }

     /**
      * Called when the view navigates.
      */
     @Override
     public void onReset() {
         if (this.status == AccelListener.RUNNING) {
             this.stop();
         }
     }

     // Sends an error back to JS
     private void fail(int code, String message) {
         // Error object
         JSONObject errorObj = new JSONObject();
         try {
             errorObj.put("code", code);
             errorObj.put("message", message);
         } catch (JSONException e) {
             e.printStackTrace();
         }
         PluginResult err = new PluginResult(PluginResult.Status.ERROR, errorObj);
         err.setKeepCallback(true);
         callbackContext.sendPluginResult(err);
     }

     private void win() {
         // Success return object
         PluginResult result = new PluginResult(PluginResult.Status.OK, this.getAccelerationJSON());
         result.setKeepCallback(true);
         callbackContext.sendPluginResult(result);
     }

     private void setStatus(int status) {
         this.status = status;
     }
     private JSONObject getAccelerationJSON() {
         JSONObject r = new JSONObject();
         try {
             r.put("x", this.x);
             r.put("y", this.y);
             r.put("z", this.z);
             r.put("timestamp", this.timestamp);
         } catch (JSONException e) {
             e.printStackTrace();
         }
         return r;
     }
 }
	/*
	Licensed to the Apache Software Foundation (ASF) under one
	or more contributor license agreements. See the NOTICE file
	distributed with this work for additional information
	regarding copyright ownership. The ASF licenses this file
	to you under the Apache License, Version 2.0 (the
	"License"); you may not use this file except in compliance
	with the License. You may obtain a copy of the License at

	http://www.apache.org/licenses/LICENSE-2.0

	Unless required by applicable law or agreed to in writing,
	software distributed under the License is distributed on an
	"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
	KIND, either express or implied. See the License for the
	specific language governing permissions and limitations
	under the License.
	*/
	package org.apache.cordova.devicemotion;

	import java.util.List;

	import org.apache.cordova.CordovaWebView;
	import org.apache.cordova.CallbackContext;
	import org.apache.cordova.CordovaInterface;
	import org.apache.cordova.CordovaPlugin;
	import org.apache.cordova.PluginResult;
	import org.json.JSONArray;
	import org.json.JSONException;
	import org.json.JSONObject;

	import android.content.Context;
	import android.hardware.Sensor;
	import android.hardware.SensorEvent;
	import android.hardware.SensorEventListener;
	import android.hardware.SensorManager;

	import android.os.Handler;
	import android.os.Looper;

	/**
	* This class listens to the accelerometer sensor and stores the latest
	* acceleration values x,y,z.
	*/
	public class AccelListener extends CordovaPlugin implements SensorEventListener {

	public static int STOPPED = 0;
	public static int STARTING = 1;
	public static int RUNNING = 2;
	public static int ERROR_FAILED_TO_START = 3;

	private float x,y,z; // most recent acceleration values
	private long timestamp; // time of most recent value
	private int status; // status of listener
	private int accuracy = SensorManager.SENSOR_STATUS_ACCURACY_MEDIUM;

	private SensorManager sensorManager; // Sensor manager
	private Sensor mSensor; // Acceleration sensor returned by sensor manager

	private CallbackContext callbackContext; // Keeps track of the JS callback context.

	private Handler mainHandler=null;
	private Runnable mainRunnable =new Runnable() {
	public void run() {
	AccelListener.this.timeout();
	}
	};

	/**
	* Create an accelerometer listener.
	*/
	public AccelListener() {
	this.x = 0;
	this.y = 0;
	this.z = 0;
	this.timestamp = 0;
	this.setStatus(AccelListener.STOPPED);
	}

	/**
	* Sets the context of the Command. This can then be used to do things like
	* get file paths associated with the Activity.
	*
	* @param cordova The context of the main Activity.
	* @param webView The associated CordovaWebView.
	*/
	@Override
	public void initialize(CordovaInterface cordova, CordovaWebView webView) {
	super.initialize(cordova, webView);
	this.sensorManager = (SensorManager) cordova.getActivity().getSystemService(Context.SENSOR_SERVICE);
	}

	/**
	* Executes the request.
	*
	* @param action The action to execute.
	* @param args The exec() arguments.
	* @param callbackId The callback id used when calling back into JavaScript.
	* @return Whether the action was valid.
	*/
	public boolean execute(String action, JSONArray args, CallbackContext callbackContext) {
	if (action.equals("start")) {
	this.callbackContext = callbackContext;
	if (this.status != AccelListener.RUNNING) {
	// If not running, then this is an async call, so don't worry about waiting
	// We drop the callback onto our stack, call start, and let start and the sensor callback fire off the callback down the road
	this.start();
	}
	}
	else if (action.equals("stop")) {
	if (this.status == AccelListener.RUNNING) {
	this.stop();
	}
	} else {
	// Unsupported action
	return false;
	}

	PluginResult result = new PluginResult(PluginResult.Status.NO_RESULT, "");
	result.setKeepCallback(true);
	callbackContext.sendPluginResult(result);
	return true;
	}

	/**
	* Called by AccelBroker when listener is to be shut down.
	* Stop listener.
	*/
	public void onDestroy() {
	this.stop();
	}

	//--------------------------------------------------------------------------
	// LOCAL METHODS
	//--------------------------------------------------------------------------
	//
	/**
	* Start listening for acceleration sensor.
	*
	* @return status of listener
	*/
	private int start() {
	// If already starting or running, then restart timeout and return
	if ((this.status == AccelListener.RUNNING) \|\| (this.status == AccelListener.STARTING)) {
	startTimeout();
	return this.status;
	}

	this.setStatus(AccelListener.STARTING);

	// Get accelerometer from sensor manager
	List<Sensor> list = this.sensorManager.getSensorList(Sensor.TYPE_ACCELEROMETER);

	// If found, then register as listener
	if ((list != null) && (list.size() > 0)) {
	this.mSensor = list.get(0);
	if (this.sensorManager.registerListener(this, this.mSensor, SensorManager.SENSOR_DELAY_UI)) {
	this.setStatus(AccelListener.STARTING);
	} else {
	this.setStatus(AccelListener.ERROR_FAILED_TO_START);
	this.fail(AccelListener.ERROR_FAILED_TO_START, "Device sensor returned an error.");
	return this.status;
	};

	} else {
	this.setStatus(AccelListener.ERROR_FAILED_TO_START);
	this.fail(AccelListener.ERROR_FAILED_TO_START, "No sensors found to register accelerometer listening to.");
	return this.status;
	}

	startTimeout();

	return this.status;
	}
	private void startTimeout() {
	// Set a timeout callback on the main thread.
	stopTimeout();
	mainHandler = new Handler(Looper.getMainLooper());
	mainHandler.postDelayed(mainRunnable, 2000);
	}
	private void stopTimeout() {
	if(mainHandler!=null){
	mainHandler.removeCallbacks(mainRunnable);
	}
	}
	/**
	* Stop listening to acceleration sensor.
	*/
	private void stop() {
	stopTimeout();
	if (this.status != AccelListener.STOPPED) {
	this.sensorManager.unregisterListener(this);
	}
	this.setStatus(AccelListener.STOPPED);
	this.accuracy = SensorManager.SENSOR_STATUS_UNRELIABLE;
	}

	/**
	* Returns latest cached position if the sensor hasn't returned newer value.
	*
	* Called two seconds after starting the listener.
	*/
	private void timeout() {
	if (this.status == AccelListener.STARTING) {
	// call win with latest cached position
	this.timestamp = System.currentTimeMillis();
	this.win();
	}
	}

	/**
	* Called when the accuracy of the sensor has changed.
	*
	* @param sensor
	* @param accuracy
	*/
	public void onAccuracyChanged(Sensor sensor, int accuracy) {
	// Only look at accelerometer events
	if (sensor.getType() != Sensor.TYPE_ACCELEROMETER) {
	return;
	}

	// If not running, then just return
	if (this.status == AccelListener.STOPPED) {
	return;
	}
	this.accuracy = accuracy;
	}

	/**
	* Sensor listener event.
	*
	* @param SensorEvent event
	*/
	public void onSensorChanged(SensorEvent event) {
	// Only look at accelerometer events
	if (event.sensor.getType() != Sensor.TYPE_ACCELEROMETER) {
	return;
	}

	// If not running, then just return
	if (this.status == AccelListener.STOPPED) {
	return;
	}
	this.setStatus(AccelListener.RUNNING);

	if (this.accuracy >= SensorManager.SENSOR_STATUS_ACCURACY_MEDIUM) {

	// Save time that event was received
	this.timestamp = System.currentTimeMillis();
	this.x = event.values[0];
	this.y = event.values[1];
	this.z = event.values[2];

	this.win();
	}
	}

	/**
	* Called when the view navigates.
	*/
	@Override
	public void onReset() {
	if (this.status == AccelListener.RUNNING) {
	this.stop();
	}
	}

	// Sends an error back to JS
	private void fail(int code, String message) {
	// Error object
	JSONObject errorObj = new JSONObject();
	try {
	errorObj.put("code", code);
	errorObj.put("message", message);
	} catch (JSONException e) {
	e.printStackTrace();
	}
	PluginResult err = new PluginResult(PluginResult.Status.ERROR, errorObj);
	err.setKeepCallback(true);
	callbackContext.sendPluginResult(err);
	}

	private void win() {
	// Success return object
	PluginResult result = new PluginResult(PluginResult.Status.OK, this.getAccelerationJSON());
	result.setKeepCallback(true);
	callbackContext.sendPluginResult(result);
	}

	private void setStatus(int status) {
	this.status = status;
	}
	private JSONObject getAccelerationJSON() {
	JSONObject r = new JSONObject();
	try {
	r.put("x", this.x);
	r.put("y", this.y);
	r.put("z", this.z);
	r.put("timestamp", this.timestamp);
	} catch (JSONException e) {
	e.printStackTrace();
	}
	return r;
	}
	}