Add android support and changed API a bit

Author: Viktor Nilsson

.gitignore

@@ -1,2 +1,3 @@
 ios/RNSimpleCompass.xcodeproj/project.xcworkspace/
 ios/RNSimpleCompass.xcodeproj/xcuserdata/
+.DS_Store

android/src/main/java/com/reactlibrary/RNSimpleCompassModule.java

@@ -1,22 +1,89 @@
 
 package com.reactlibrary;
 
+import android.hardware.Sensor;
+import android.hardware.SensorEvent;
+import android.hardware.SensorEventListener;
+import android.hardware.SensorManager;
+
+import android.content.Context;
+import com.facebook.react.modules.core.DeviceEventManagerModule;
+import com.facebook.react.bridge.Arguments;
+
 import com.facebook.react.bridge.ReactApplicationContext;
 import com.facebook.react.bridge.ReactContextBaseJavaModule;
 import com.facebook.react.bridge.ReactMethod;
 import com.facebook.react.bridge.Callback;
 
-public class RNSimpleCompassModule extends ReactContextBaseJavaModule {
+public class RNSimpleCompassModule extends ReactContextBaseJavaModule implements SensorEventListener {
 
   private final ReactApplicationContext reactContext;
 
+  private static Context mApplicationContext;
+  private int mAzimuth = 0; // degree
+  private int mFilter = 1;
+  private SensorManager mSensorManager;
+  private Sensor mSensor;
+  private float[] orientation = new float[3];
+  private float[] rMat = new float[9];
+
   public RNSimpleCompassModule(ReactApplicationContext reactContext) {
     super(reactContext);
     this.reactContext = reactContext;
+    mApplicationContext = reactContext.getApplicationContext();
   }
 
   @Override
   public String getName() {
     return "RNSimpleCompass";
   }
-}
+
+  @ReactMethod
+  public void start(int filter) {
+
+      if (mSensorManager == null) {
+          mSensorManager = (SensorManager) mApplicationContext.getSystemService(Context.SENSOR_SERVICE);
+      }
+
+      if (mSensor == null) {
+          mSensor = mSensorManager.getDefaultSensor(Sensor.TYPE_ROTATION_VECTOR);
+      }
+
+      mFilter = filter;
+      mSensorManager.registerListener(this, mSensor, SensorManager.SENSOR_DELAY_UI);
+  }
+
+  @ReactMethod
+  public void stop() {
+    if (mSensorManager != null) {
+      mSensorManager.unregisterListener(this);
+    }
+  }
+
+  @Override
+  public void onSensorChanged(SensorEvent event) {
+      if( event.sensor.getType() == Sensor.TYPE_ROTATION_VECTOR ){
+          // calculate th rotation matrix
+          SensorManager.getRotationMatrixFromVector(rMat, event.values);
+          // get the azimuth value (orientation[0]) in degree
+          int newAzimuth = (int) ( Math.toDegrees( SensorManager.getOrientation( rMat, orientation )[0] ) + 360 ) % 360;
+
+          //dont react to changes smaller than the filter value
+          if (Math.abs(mAzimuth - newAzimuth) < mFilter) {
+              return;
+          }
+
+          mAzimuth = newAzimuth;
+
+          getReactApplicationContext()
+                  .getJSModule(DeviceEventManagerModule.RCTDeviceEventEmitter.class)
+                  .emit("HeadingUpdated", mAzimuth);
+      }
+  }
+
+
+  @Override
+  public void onAccuracyChanged(Sensor sensor, int accuracy) {
+
+  }
+}

ios/RNSimpleCompass.h

@@ -1,8 +1,7 @@
 
-#import "RCTBridgeModule.h"
-#import "RCTEventEmitter.h"
+#import <React/RCTBridgeModule.h>
+#import <React/RCTEventEmitter.h>
 
 @interface RNSimpleCompass : RCTEventEmitter <RCTBridgeModule>
 
 @end
-  

ios/RNSimpleCompass.m

@@ -1,11 +1,8 @@
-
-#import "RNSimpleCompass.h"
-#import "RCTEventDispatcher.h"
-#import "RCTLog.h"
+#import <React/RNSimpleCompass.h>
+#import <React/RCTEventDispatcher.h>
 #import <Corelocation/CoreLocation.h>
 
 #define kHeadingUpdated @"HeadingUpdated"
-#define kDefauktHeadingFilter 1
 
 @interface RNSimpleCompass() <CLLocationManagerDelegate>
 @property (strong, nonatomic) CLLocationManager *locationManager;
@@ -27,7 +24,7 @@ - (instancetype)init {
             NSLog(@"Heading not available");
         }
     }
-    
+
     return self;
 }
 
@@ -62,9 +59,7 @@ - (BOOL)locationManagerShouldDisplayHeadingCalibration:(CLLocationManager *)mana
 
 #pragma mark - React
 
-RCT_EXPORT_METHOD(start: (NSDictionary *)params) {
-    NSNumber *accuracy = [params objectForKey:@"accuracy"];
-    NSInteger headingFilter = accuracy ? [accuracy doubleValue] : kDefauktHeadingFilter;
+RCT_EXPORT_METHOD(start: (NSInteger) headingFilter) {
     self.locationManager.headingFilter = headingFilter;
     [self.locationManager startUpdatingHeading];
 }

package.json

@@ -1,8 +1,8 @@
 
 {
   "name": "react-native-simple-compass",
-  "version": "0.0.1",
-  "description": "Simple module exposing the compass on iOS",
+  "version": "0.0.2",
+  "description": "Simple module exposing the compass on iOS and Android",
   "main": "index.js",
   "scripts": {
     "test": "echo \"Error: no test specified\" && exit 1"