com.google.appinventor.components.runtime.LightSensor.java Source code

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Here is the source code for com.google.appinventor.components.runtime.LightSensor.java

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// -*- mode: java; c-basic-offset: 2; -*-
// Copyright 2009-2011 Google, All Rights reserved
// Copyright 2011-2012 MIT, All rights reserved
// Released under the MIT License https://raw.github.com/mit-cml/app-inventor/master/mitlicense.txt

package com.google.appinventor.components.runtime;

import android.os.Handler;
import android.os.Message;
import android.util.Log;

import com.google.appinventor.components.annotations.*;
import com.google.appinventor.components.common.ComponentCategory;
import com.google.appinventor.components.common.PropertyTypeConstants;
import com.google.appinventor.components.common.YaVersion;
import com.google.gson.GsonBuilder;
import com.google.gson.JsonElement;
import com.google.gson.JsonObject;

import edu.mit.media.funf.FunfManager;
import edu.mit.media.funf.json.IJsonObject;
import edu.mit.media.funf.probe.Probe.DataListener;
import edu.mit.media.funf.probe.builtin.LightSensorProbe;
import edu.mit.media.funf.probe.builtin.ProbeKeys;
import edu.mit.media.funf.probe.builtin.RunningApplicationsProbe;

@DesignerComponent(version = YaVersion.LIGHTSENSOR_COMPONENT_VERSION, description = "Return information of the current illuminances (lux) by using the light sensor ", category = ComponentCategory.SENSORS, nonVisible = true, iconName = "images/lightsensorProbe.png")
@SimpleObject
@UsesLibraries(libraries = "funf.jar")
public class LightSensor extends ProbeBase {

    private final String TAG = "LightSensor";
    private LightSensorProbe probe;
    private final String LIGHTSENSOR_PROBE = "edu.mit.media.funf.probe.builtin.LightSensorProbe";

    private int lux;
    private long timestamp;

    //default settings for schedule 
    private final int SCHEDULE_INTERVAL = 1800; //read illuminances every 1800 seconds (30 minutes)
    private final int SCHEDULE_DURATION = 15; //scan for 15 seconds everytime

    public LightSensor(ComponentContainer container) {
        super(container);
        // TODO Auto-generated constructor stub

        form.registerForOnDestroy(this);

        mainUIThreadActivity = container.$context();
        Log.i(TAG, "Before create probe");
        gson = new GsonBuilder().registerTypeAdapterFactory(FunfManager.getProbeFactory(mainUIThreadActivity))
                .create();
        JsonObject config = new JsonObject();

        probe = gson.fromJson(config, LightSensorProbe.class);

        interval = SCHEDULE_INTERVAL;
        duration = SCHEDULE_DURATION;

    }

    private DataListener listener = new DataListener() {
        @Override
        public void onDataCompleted(IJsonObject completeProbeUri, JsonElement arg1) {
            //do nothing. LightSensorProbe does not have onDataComplete event
        }

        @Override
        public void onDataReceived(IJsonObject completeProbeUri, IJsonObject data) {
            Log.i(TAG, "receive data of illuminances");
            /* returned json format 
              {"accuracy":0,"lux":100.0,"timestamp":946695643.291918}
             */
            //debug

            Log.i(TAG, "DATA: " + data.toString());
            //debug

            //save data to DB is enabledSaveToDB is true
            if (enabledSaveToDB) {

                saveToDB(completeProbeUri, data);
            }

            Message msg = myHandler.obtainMessage();
            msg.obj = data;
            myHandler.sendMessage(msg);

        }

    };

    final Handler myHandler = new Handler() {
        @Override
        public void handleMessage(Message msg) {

            IJsonObject data = (IJsonObject) msg.obj;
            Log.i(TAG, "Update component's varibles.....");

            lux = data.get(ProbeKeys.LightSensorKeys.LUX).getAsInt();
            timestamp = data.get(ProbeKeys.LightSensorKeys.TIMESTAMP).getAsLong();

            Log.i(TAG, " before call LightInfoReceived()");
            LightInfoReceived();
            Log.i(TAG, " after call LightInfoReceived()");

        }

    };

    /**
     * Indicates whether the sensor should "run once" to read the current illuminance
     */

    @SimpleFunction(description = "Enable light sensor probe to run once")
    @Override
    public void Enabled(boolean enabled) {
        // TODO Auto-generated method stub
        if (this.enabled != enabled)
            this.enabled = enabled;

        if (enabled) {
            probe.registerListener(listener);
            Log.i(TAG, "register listener for run-once");
        } else {
            probe.unregisterListener(listener);
            Log.i(TAG, "unregister run-once listener");
        }

    }

    @Override
    public void unregisterDataRequest() {
        // TODO Auto-generated method stub
        Log.i(TAG, "Unregistering data requests.");
        mBoundFunfManager.unrequestAllData2(listener);

        Log.i(TAG, "After Unregistering data requests.");

    }

    @Override
    public void registerDataRequest(int interval, int duration) {
        // TODO Auto-generated method stub
        Log.i(TAG, "Registering data requests.");
        JsonElement dataRequest = null;

        dataRequest = getDataRequest(interval, duration, LIGHTSENSOR_PROBE);
        Log.i(TAG, "Data request: " + dataRequest.toString());
        mBoundFunfManager.requestData(listener, dataRequest);
    }

    /**
     * Indicates that the illuminance(light) info has been received.
     */
    @SimpleEvent
    public void LightInfoReceived() {
        if (enabled || enabledSchedule) {

            mainUIThreadActivity.runOnUiThread(new Runnable() {
                public void run() {
                    Log.i(TAG, "LightInfoReceived() is called");
                    EventDispatcher.dispatchEvent(LightSensor.this, "LightInfoReceived");
                }
            });

        }

    }

    /**
     * Returns whether the screen is currently on
     */
    @SimpleProperty(description = "The illuminance(lux) of light in the current environment.")
    public int Lux() {
        Log.i(TAG, "returning lux: " + lux);
        return lux;
    }

    /**
     * Returns the timestamp of latest reading 
     */
    @SimpleProperty(description = "The timestamp of this sensor event.")
    public float Timestamp() {
        Log.i(TAG, "returning timestamp: " + timestamp);
        return timestamp;
    }

    /*
     * Returns the default interval between each scan for this probe
     */
    @SimpleProperty(description = "The default interval (in seconds) between each scan for this probe")
    public float DefaultInterval() {

        return SCHEDULE_INTERVAL;
    }

    /*
     * Returns the default duration of each scan for this probe
     */
    @SimpleProperty(description = "The default duration (in seconds) of each scan for this probe")
    public float DefaultDuration() {

        return SCHEDULE_DURATION;
    }
}