Refactor codes

app/src/main/java/com/example/minhduc0711/indoorlocalization/MainActivity.java

@@ -10,8 +10,16 @@
 import android.os.Bundle;
 import android.support.v4.app.ActivityCompat;
 import android.support.v7.app.AppCompatActivity;
+import android.view.View;
+import android.widget.AdapterView;
+import android.widget.Spinner;
 
-public class MainActivity extends AppCompatActivity implements SensorEventListener {
+import com.example.minhduc0711.indoorlocalization.models.PredictiveModel;
+import com.example.minhduc0711.indoorlocalization.models.ScikitModel;
+import com.example.minhduc0711.indoorlocalization.models.TensorflowModel;
+
+public class MainActivity extends AppCompatActivity implements SensorEventListener, AdapterView.OnItemSelectedListener {
+    private Spinner mModelSpinner;
     private MapView mMapView;
 
     private SensorManager mSensorManager;
@@ -32,8 +40,36 @@ protected void onCreate(Bundle savedInstanceState) {
         mMapView.getHolder().setFormat(PixelFormat.TRANSPARENT);
 
         mSensorManager = (SensorManager) getSystemService(SENSOR_SERVICE);
+
+//        mModelSpinner = findViewById(R.id.model_spinner);
+//        ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(this,
+//                R.array.models_array, android.R.layout.simple_spinner_item);
+//        adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
+//        mModelSpinner.setAdapter(adapter);
+//        mModelSpinner.setOnItemSelectedListener(this);
+//        mModelSpinner.setSelection(0);
     }
 
+    @Override
+    public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
+        String selected = (String) parent.getItemAtPosition(position);
+        PredictiveModel newModel;
+        switch (selected) {
+            case "Neural network":
+                newModel = new TensorflowModel("neural_net.pb", this);
+                break;
+            case "Decision tree":
+                newModel = new ScikitModel("decision_tree_x.pmml.ser", "decision_tree_y.pmml.ser", this);
+                break;
+            default:
+                throw new RuntimeException();
+        }
+        mMapView.initializeModel(newModel);
+    }
+
+    @Override
+    public void onNothingSelected(AdapterView<?> parent) {}
+
     @Override
     protected void onResume() {
         super.onResume();

app/src/main/java/com/example/minhduc0711/indoorlocalization/MapView.java

@@ -13,14 +13,17 @@
 import android.view.SurfaceView;
 import android.widget.Toast;
 
+import com.example.minhduc0711.indoorlocalization.models.PredictiveModel;
+import com.example.minhduc0711.indoorlocalization.models.ScikitModel;
+import com.example.minhduc0711.indoorlocalization.models.TensorflowModel;
+
 import org.json.JSONException;
 import org.json.JSONObject;
 
 import java.util.List;
 
 public class MapView extends SurfaceView implements SurfaceHolder.Callback {
     private static final String TRAIN_IDX_DICT_PATH = "cleaned_idx_dict.json";
-    private static final String MODEL_NAME = "model";
 
     private final static float X_MAX = 20;
     private final static float Y_MAX = 40;
@@ -48,18 +51,23 @@ public MapView(Context context, AttributeSet attrs) {
 
         mPositionIndicator = new PositionIndicator();
 
-        mWifiManager = (WifiManager) context.getSystemService(Context.WIFI_SERVICE);
+        mWifiManager = (WifiManager) context.getApplicationContext().getSystemService(Context.WIFI_SERVICE);
         if (mWifiManager.getWifiState() == WifiManager.WIFI_STATE_DISABLED) {
             Toast.makeText(getContext(), "Enabling Wifi...", Toast.LENGTH_LONG).show();
             mWifiManager.setWifiEnabled(true);
         }
 
-        mPredictiveModel = new PredictiveModel(context, PredictiveModel.PB_FILE_EXT, MODEL_NAME);
+        initializeModel(new TensorflowModel("neural_net.pb", context));
+//        initializeModel(new ScikitModel("decision_tree_x.pmml.ser", "decision_tree_y.pmml.ser", context));
         trainIndexDict = Utils.loadJSONFromAsset(TRAIN_IDX_DICT_PATH, context);
 
         mDrawThread = new DrawThread();
     }
 
+    public void initializeModel(PredictiveModel newModel) {
+        mPredictiveModel = newModel;
+    }
+
     /**
      * Converts the wifi status to a feature vector
      */
@@ -89,18 +97,9 @@ private void updatePositionIndicator() {
         if (mWifiManager.getWifiState() == WifiManager.WIFI_STATE_ENABLED) {
             List<ScanResult> wifiResults = mWifiManager.getScanResults();
 
-            long startTime = System.nanoTime();
             float[] input = toFeatureVector(wifiResults);
             float[] output = mPredictiveModel.predict(input);
-            long endTime = System.nanoTime();
 
-            long duration = (endTime - startTime);
-//            Log.d("output", Arrays.toString(output));
-
-//            Random r = new Random();
-//            int x = r.nextInt((int) X_MAX);
-//            Random r1 = new Random();
-//            int y = r1.nextInt((int) Y_MAX);
             mPositionIndicator.update(Math.round(output[0]), Math.round(output[1]));
         }
     }
@@ -112,13 +111,6 @@ public void updateOrientation(int angle) {
         mDeviceOrientation = angle;
     }
 
-    /**
-     * Performs the actual drawing on the SurfaceView
-     */
-    private void doDraw() {
-
-    }
-
     @Override
     public void surfaceCreated(SurfaceHolder holder) {
         threadRunning = true;
@@ -160,7 +152,7 @@ public void run() {
                 long endTime = System.currentTimeMillis();
                 long deltaTime = endTime - startTime;
 
-                if(deltaTime < 200)
+                if (deltaTime < 200)
                 {
                     try {
                         Thread.sleep(200 - deltaTime);

app/src/main/java/com/example/minhduc0711/indoorlocalization/Utils.java

@@ -13,19 +13,6 @@
 import java.io.InputStream;
 
 public class Utils {
-    public static Bitmap drawableToBitmap(Drawable drawable) {
-        if (drawable instanceof BitmapDrawable) {
-            return ((BitmapDrawable) drawable).getBitmap();
-        }
-
-        Bitmap bitmap = Bitmap.createBitmap(drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight(), Bitmap.Config.ARGB_8888);
-        Canvas canvas = new Canvas(bitmap);
-        drawable.setBounds(0, 0, canvas.getWidth(), canvas.getHeight());
-        drawable.draw(canvas);
-
-        return bitmap;
-    }
-
     public static JSONObject loadJSONFromAsset(String fname, Context context) {
         String json;
         try {

app/src/main/java/com/example/minhduc0711/indoorlocalization/models/PredictiveModel.java

@@ -0,0 +1,5 @@
+package com.example.minhduc0711.indoorlocalization.models;
+
+public interface PredictiveModel {
+    float[] predict(float[] input);
+}

app/src/main/java/com/example/minhduc0711/indoorlocalization/models/ScikitModel.java

@@ -0,0 +1,49 @@
+package com.example.minhduc0711.indoorlocalization.models;
+
+import android.content.Context;
+
+import org.dmg.pmml.FieldName;
+import org.jpmml.android.EvaluatorUtil;
+import org.jpmml.evaluator.FieldValue;
+import org.jpmml.evaluator.InputField;
+import org.jpmml.evaluator.ModelEvaluator;
+
+import java.io.InputStream;
+import java.util.HashMap;
+import java.util.Map;
+
+public class ScikitModel implements PredictiveModel {
+    private ModelEvaluator<?> mEvaluatorX;
+    private ModelEvaluator<?> mEvaluatorY;
+
+    public ScikitModel(String fileNameX, String fileNameY, Context context) {
+        try {
+            InputStream is = context.getAssets().open(fileNameX);
+            mEvaluatorX = (ModelEvaluator<?>) EvaluatorUtil.createEvaluator(is);
+            is = context.getAssets().open(fileNameY);
+            mEvaluatorY = (ModelEvaluator<?>) EvaluatorUtil.createEvaluator(is);
+        } catch (Exception e) {
+            e.printStackTrace();
+        }
+    }
+
+    @Override
+    public float[] predict(float[] input) {
+        float[] output = new float[2];
+
+        int i = 0;
+        Map<FieldName, FieldValue> inputMap = new HashMap<>();
+        for (InputField inputField : mEvaluatorX.getInputFields()) {
+            FieldName fieldName = inputField.getName();
+            Object rawValue = input[i++];
+            FieldValue fieldValue = inputField.prepare(rawValue);
+            inputMap.put(fieldName, fieldValue);
+        }
+        Map<String, ?> resultsX = org.jpmml.evaluator.EvaluatorUtil.decode(mEvaluatorX.evaluate(inputMap));
+        Map<String, ?> resultsY = org.jpmml.evaluator.EvaluatorUtil.decode(mEvaluatorY.evaluate(inputMap));
+        output[0] = ((Double) resultsX.get("y")).floatValue();
+        output[1] = ((Double) resultsY.get("y")).floatValue();
+
+        return output;
+    }
+}

app/src/main/java/com/example/minhduc0711/indoorlocalization/models/TensorflowModel.java

@@ -0,0 +1,25 @@
+package com.example.minhduc0711.indoorlocalization.models;
+
+import android.content.Context;
+
+import org.tensorflow.contrib.android.TensorFlowInferenceInterface;
+
+public class TensorflowModel implements PredictiveModel {
+    private TensorFlowInferenceInterface mInferenceInterface;
+
+    public TensorflowModel(String fileName, Context context) {
+        mInferenceInterface = new TensorFlowInferenceInterface(context.getAssets(), fileName);
+    }
+
+    @Override
+    public float[] predict(float[] input) {
+        float[] output = new float[2];
+
+        String[] outputNames = {"output_node0"};
+        mInferenceInterface.feed("dense_55_input", input, 1, input.length);
+        mInferenceInterface.run(outputNames);
+        mInferenceInterface.fetch(outputNames[0], output);
+
+        return output;
+    }
+}

app/src/main/res/layout/activity_main.xml

@@ -5,6 +5,23 @@
     android:layout_height="match_parent"
     xmlns:android="http://schemas.android.com/apk/res/android">
 
+    <!--<LinearLayout-->
+        <!--android:layout_width="match_parent"-->
+        <!--android:layout_height="wrap_content"-->
+        <!--android:orientation="vertical">-->
+
+        <!--<TextView-->
+            <!--android:layout_width="wrap_content"-->
+            <!--android:layout_height="wrap_content"-->
+            <!--android:text="Select model"/>-->
+
+        <!--<Spinner-->
+            <!--android:id="@+id/model_spinner"-->
+            <!--android:layout_width="match_parent"-->
+            <!--android:layout_height="wrap_content" />-->
+
+    <!--</LinearLayout>-->
+
     <FrameLayout android:layout_height="match_parent"
         android:layout_width="match_parent"
         android:id="@+id/frame_layout_main"