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最近、GPS とマーカーを使用して現在地を特定する方法を学んでいます。そして今、コードが現在の場所を追跡し、場所が更新されたときに移動した合計距離を計算できるように変更しようとしています。最初は、それは機能します。しかし、2 ～ 3 分後、アプリがハングし始め、アプリケーションからの応答がないため、強制的に閉じるように求められます。

以下は私のコードです：

public class WhereAmINowActivity extends Activity {
//declaration of variables

public void getPrevActivityValue(){
    Intent intent = getIntent();
    // get the value from prev activity
}



@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.start_distance);
    getPrevActivityValue();
    btnStart = (Button)findViewById(R.id.btnStart);
    btnStop = (Button)findViewById(R.id.btnStop);
    distance = (TextView)findViewById(R.id.distance);

    locationManager = (LocationManager)getSystemService(Context.LOCATION_SERVICE);

    Criteria criteria = new Criteria();
    criteria.setAccuracy(Criteria.ACCURACY_FINE);
    criteria.setAltitudeRequired(false);
    criteria.setBearingRequired(false);
    criteria.setCostAllowed(true);
    criteria.setPowerRequirement(Criteria.POWER_LOW);
    provider = locationManager.getBestProvider(criteria, true);

    location = locationManager.getLastKnownLocation(provider);

    updateWithNewLocation(location);

    locationManager.requestLocationUpdates(provider, TWO_MIN, HUNDRED_METERS ,locationListener);

    addListenerOnBtnStart();
    addListenerOnBtnStop();
}

public void addListenerOnBtnStart(){
    btnStart.setOnClickListener(new View.OnClickListener(){
      public void onClick(View paramAnonymousView){
        if(!startPressed){
// Initialize the variables of current and old location coordinates

            }
            catch (Exception e){
                e.printStackTrace();
            }
        }
        else{
            // Do nothing
        }
      }
    });
}

public void addListenerOnBtnStop(){
    btnStop.setOnClickListener(new View.OnClickListener(){
      public void onClick(View paramAnonymousView){
        try{

            if(connected to internet is true)

// Do something here

                }
                else{
// prompt message to notify user connectivity is not available
                }
        }
        catch (Exception e){
            e.printStackTrace();
        }
      }
    });
}


  private final LocationListener locationListener = new LocationListener() {
        public void onLocationChanged(Location location) {
          updateWithNewLocation(location);
        }

        public void onProviderDisabled(String provider){
          updateWithNewLocation(null);
        }

        public void onProviderEnabled(String provider){ }
        public void onStatusChanged(String provider, int status, 
                                    Bundle extras){ }
      };

      private void updateWithNewLocation(Location location) {

// Update the current location, old coordinates and get the address 

        }


}

値の一部は、getIntent() を使用して前のアクティビティから渡されます。

誰かが私が間違ってやった部分を理解するのを手伝ってもらえますか?

追加: オーバーレイを削除し、ロケーション リスナーのみでテストしました。約2〜3分実行すると、アプリのインターフェースが押したものに応答しないことがわかりました（開始と停止の2つのボタンを宣言しているため）。停止ボタンを押しても何も起こらず、強制終了のメッセージが表示されます。これは私が間違った部分ですか？GPS を使って歩いているときに、通常の距離計算のように機能するには、どのように修正すればよいですか?

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1 に答える 1

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私はオープンソースの Gps Tracker でこの正確な問題を解決しました。完全に機能する Android プロジェクトは次のとおりです。

https://github.com/nickfox/GpsTracker/tree/master/phoneClients/android

追跡を行うクラスは以下のとおりです。totalDistanceInMeters という変数を調べます。

package com.websmithing.gpstracker;

import android.app.Service;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.location.Location;
import android.os.Bundle;
import android.os.IBinder;
import android.util.Log;

import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.GooglePlayServicesClient;
import com.google.android.gms.common.GooglePlayServicesUtil;
import com.google.android.gms.location.LocationClient;
import com.google.android.gms.location.LocationListener;
import com.google.android.gms.location.LocationRequest;
import com.loopj.android.http.AsyncHttpResponseHandler;
import com.loopj.android.http.RequestParams;

import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.TimeZone;

public class LocationService extends Service implements
        GooglePlayServicesClient.ConnectionCallbacks,
        GooglePlayServicesClient.OnConnectionFailedListener,
        LocationListener {

    private static final String TAG = "LocationService";

    // use the websmithing defaultUploadWebsite for testing and then check your
    // location with your browser here: https://www.websmithing.com/gpstracker/displaymap.php
    private String defaultUploadWebsite;

    private boolean currentlyProcessingLocation = false;
    private LocationRequest locationRequest;
    private LocationClient locationClient;

    @Override
    public void onCreate() {
        super.onCreate();

        defaultUploadWebsite = getString(R.string.default_upload_website);
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        // if we are currently trying to get a location and the alarm manager has called this again,
        // no need to start processing a new location.
        if (!currentlyProcessingLocation) {
            currentlyProcessingLocation = true;
            startTracking();
        }

        return START_NOT_STICKY;
    }

    private void startTracking() {
        Log.d(TAG, "startTracking");

        if (GooglePlayServicesUtil.isGooglePlayServicesAvailable(this) == ConnectionResult.SUCCESS) {
            locationClient = new LocationClient(this,this,this);

            if (!locationClient.isConnected() || !locationClient.isConnecting()) {
                locationClient.connect();
            }
        } else {
            Log.e(TAG, "unable to connect to google play services.");
        }
    }

    protected void sendLocationDataToWebsite(Location location) {
        // formatted for mysql datetime format
        DateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        dateFormat.setTimeZone(TimeZone.getDefault());
        Date date = new Date(location.getTime());

        SharedPreferences sharedPreferences = this.getSharedPreferences("com.websmithing.gpstracker.prefs", Context.MODE_PRIVATE);
        SharedPreferences.Editor editor = sharedPreferences.edit();

        float totalDistanceInMeters = sharedPreferences.getFloat("totalDistanceInMeters", 0f);

        boolean firstTimeGettingPosition = sharedPreferences.getBoolean("firstTimeGettingPosition", true);

        if (firstTimeGettingPosition) {
            editor.putBoolean("firstTimeGettingPosition", false);
        } else {
            Location previousLocation = new Location("");
            previousLocation.setLatitude(sharedPreferences.getFloat("previousLatitude", 0f));
            previousLocation.setLongitude(sharedPreferences.getFloat("previousLongitude", 0f));

            float distance = location.distanceTo(previousLocation);
            totalDistanceInMeters += distance;
            editor.putFloat("totalDistanceInMeters", totalDistanceInMeters);
        }

        editor.putFloat("previousLatitude", (float)location.getLatitude());
        editor.putFloat("previousLongitude", (float)location.getLongitude());
        editor.apply();

        final RequestParams requestParams = new RequestParams();
        requestParams.put("latitude", Double.toString(location.getLatitude()));
        requestParams.put("longitude", Double.toString(location.getLongitude()));

        Double speedInMilesPerHour = location.getSpeed()* 2.2369;
        requestParams.put("speed",  Integer.toString(speedInMilesPerHour.intValue()));

        try {
            requestParams.put("date", URLEncoder.encode(dateFormat.format(date), "UTF-8"));
        } catch (UnsupportedEncodingException e) {}

        requestParams.put("locationmethod", location.getProvider());

        if (totalDistanceInMeters > 0) {
            requestParams.put("distance", String.format("%.1f", totalDistanceInMeters / 1609)); // in miles,
        } else {
            requestParams.put("distance", "0.0"); // in miles
        }

        requestParams.put("username", sharedPreferences.getString("userName", ""));
        requestParams.put("phonenumber", sharedPreferences.getString("appID", "")); // uuid
        requestParams.put("sessionid", sharedPreferences.getString("sessionID", "")); // uuid

        Double accuracyInFeet = location.getAccuracy()* 3.28;
        requestParams.put("accuracy",  Integer.toString(accuracyInFeet.intValue()));

        Double altitudeInFeet = location.getAltitude() * 3.28;
        requestParams.put("extrainfo",  Integer.toString(altitudeInFeet.intValue()));

        requestParams.put("eventtype", "android");

        Float direction = location.getBearing();
        requestParams.put("direction",  Integer.toString(direction.intValue()));

        final String uploadWebsite = sharedPreferences.getString("defaultUploadWebsite", defaultUploadWebsite);

        LoopjHttpClient.get(uploadWebsite, requestParams, new AsyncHttpResponseHandler() {
            @Override
            public void onSuccess(int statusCode, org.apache.http.Header[] headers, byte[] responseBody) {
                LoopjHttpClient.debugLoopJ(TAG, "sendLocationDataToWebsite - success", uploadWebsite, requestParams, responseBody, headers, statusCode, null);
                stopSelf();
            }
            @Override
            public void onFailure(int statusCode, org.apache.http.Header[] headers, byte[] errorResponse, Throwable e) {
                LoopjHttpClient.debugLoopJ(TAG, "sendLocationDataToWebsite - failure", uploadWebsite, requestParams, errorResponse, headers, statusCode, e);
                stopSelf();
            }
        });
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
    }

    @Override
    public IBinder onBind(Intent intent) {
        return null;
    }

    @Override
    public void onLocationChanged(Location location) {
        if (location != null) {
            Log.e(TAG, "position: " + location.getLatitude() + ", " + location.getLongitude() + " accuracy: " + location.getAccuracy());

            // we have our desired accuracy of 500 meters so lets quit this service,
            // onDestroy will be called and stop our location uodates
            if (location.getAccuracy() < 500.0f) {
                stopLocationUpdates();
                sendLocationDataToWebsite(location);
            }
        }
    }

    private void stopLocationUpdates() {
        if (locationClient != null && locationClient.isConnected()) {
            locationClient.removeLocationUpdates(this);
            locationClient.disconnect();
        }
    }

    /**
     * Called by Location Services when the request to connect the
     * client finishes successfully. At this point, you can
     * request the current location or start periodic updates
     */
    @Override
    public void onConnected(Bundle bundle) {
        Log.d(TAG, "onConnected");

        locationRequest = LocationRequest.create();
        locationRequest.setInterval(1000); // milliseconds
        locationRequest.setFastestInterval(1000); // the fastest rate in milliseconds at which your app can handle location updates
        locationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);

        locationClient.requestLocationUpdates(locationRequest, this);
    }

    /**
     * Called by Location Services if the connection to the
     * location client drops because of an error.
     */
    @Override
    public void onDisconnected() {
        Log.e(TAG, "onDisconnected");

        stopLocationUpdates();
        stopSelf();
    }

    @Override
    public void onConnectionFailed(ConnectionResult connectionResult) {
        Log.e(TAG, "onConnectionFailed");

        stopLocationUpdates();
        stopSelf();
    }
}
于 2015-03-18T22:55:17.107 に答える