我是 android 开发的新手。
我曾尝试使用网络服务获取位置地址，但是当我午餐此代码时，我发现类未找到异常。如果有人可以建议我为此提供适当的解决方案..
服务类代码....
public class MWService extends Service implements LocationListener {
private LocationManager myLocationManager;
private LocationProvider myLocationProvider;
private NotificationManager myNotificationManager;
private long frequency;
private double total_distance = 0;
private Location currentLocation;
public static final String BROADCAST_ACTION = "com.motorvehicle.android";
private final Handler handler = new Handler();
Intent intent;
private GeocoderHelper geocoder = new GeocoderHelper();
private boolean isStart=true;
private Location startLocation,endLocation;
private String startAddress="";
private String endAddress="";
private JSONArray jarray = new JSONArray();
private boolean isInternet;
//private final Handler handler = new Handler();
public void onLocationChanged(Location newLocation) {
try {
System.out.println("latitude current :"+currentLocation.getLatitude());
System.out.println("latitude current :"+currentLocation.getLongitude());
System.out.println("latitude new :"+newLocation.getLatitude());
System.out.println("latitude new :"+newLocation.getLongitude());
System.out.println("distance total :"+total_distance);
//System.out.println(distance(22.306813, 73.180239,22.301016, 73.177986, 'K') + " Kilometers\n");
double diff = 0.0;
diff = currentLocation.getLatitude()- newLocation.getLatitude();
System.out.println("difference ::"+diff);
if(diff != 0){
total_distance = total_distance + currentLocation.distanceTo(newLocation);
}
if(isStart){
isStart = false;
startLocation = newLocation;
/* if(InternetAvailable()){
//startAddress = geocoder.fetchCityName(getApplicationContext(),newLocation);
System.out.println("start address:"+startAddress);
}*/
}else{
endLocation = newLocation;
/*if(InternetAvailable()){
//endAddress = geocoder.fetchCityName(getApplicationContext(),newLocation);
System.out.println("endAddress :"+endAddress);
}*/
}
currentLocation = newLocation;
} catch (Exception e) {
currentLocation = newLocation;
e.printStackTrace();
}
}
public boolean InternetAvailable() {
Thread t = new Thread(new Runnable() {
@Override
public void run() {
// while(isStopMe){
System.out.println("This is inside ................. :");
try {
if (!checkConnection()) {
System.out.println("No Internet Connectivity");
isInternet = false;
System.out.println("First");
} else {
if (inetAddr()) {
System.out.println("Net Connectivity is Present");
isInternet = true;
System.out.println("Second");
} else {
if (mobileConnect()) {
System.out.println("THIRD");
if (inetAddr()) {
System.out
.println("Net Connectivity is Present");
isInternet = true;
System.out.println("FOURTH");
} else {
System.out
.println("No Internet Connectivity");
isInternet = false;
System.out.println("FIFTH");
}
} else {
System.out.println("No Internet Connectivity");
isInternet = false;
System.out.println("SIX");
}
}
}
} catch (Exception ex) {
System.out.println("Leak ko catch");
}
}
});
t.start();
try {
t.join();
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return isInternet;
}
public boolean checkConnection() {
boolean connected = false;
ConnectivityManager cm = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
if (cm != null) {
NetworkInfo[] netInfo = cm.getAllNetworkInfo();
for (NetworkInfo ni : netInfo) {
if ((ni.getTypeName().equalsIgnoreCase("WIFI") || ni
.getTypeName().equalsIgnoreCase("MOBILE"))
& ni.isConnected() & ni.isAvailable()) {
connected = true;
}
}
}
return connected;
}
public boolean inetAddr() {
boolean x1 = false;
try {
Socket s = new Socket();
s.connect(new InetSocketAddress("ntp-nist.ldsbc.edu",37),3000);
InputStream is = s.getInputStream();
Scanner scan = new Scanner(is);
while(scan.hasNextLine()){
System.out.println(scan.nextLine());
x1 = true;
}
} catch (IOException e) {
x1 = false;
}
return x1;
}
public boolean mobileConnect() {
boolean conn = false;
ConnectivityManager cm = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo activeNet = cm
.getNetworkInfo(ConnectivityManager.TYPE_MOBILE);
if (activeNet != null) {
conn = true;
} else {
conn = false;
}
return conn;
}
@SuppressWarnings("deprecation")
private void myNotify(String text) {
Notification notif = new Notification(R.drawable.ic_launcher, text, System
.currentTimeMillis());
PendingIntent contentIntent = PendingIntent.getActivity(this, 0,new Intent(this, MainActivity.class), 0);
notif.setLatestEventInfo(this, "MotorVehicleApp", text, contentIntent);
// notif.defaults = Notification.DEFAULT_VIBRATE;
myNotificationManager.notify((int) System.currentTimeMillis(), notif);
}
@Override
public void onCreate() {
super.onCreate();
String provider = Settings.Secure.getString(getContentResolver(), Settings.Secure.LOCATION_PROVIDERS_ALLOWED);
if(!provider.contains("gps")){ //if gps is disabled
final Intent poke = new Intent();
poke.setClassName("com.android.settings", "com.android.settings.widget.SettingsAppWidgetProvider");
poke.addCategory(Intent.CATEGORY_ALTERNATIVE);
poke.setData(Uri.parse("3"));
sendBroadcast(poke);
}
intent = new Intent(BROADCAST_ACTION);
android.util.Log.d("MWD", "creating");
myLocationManager = (LocationManager) this.getSystemService(Context.LOCATION_SERVICE);
System.out.println("location manager:"+myLocationManager.getAllProviders());
myLocationProvider = myLocationManager.getProvider("gps");
myNotificationManager = (NotificationManager) this.getSystemService(Context.NOTIFICATION_SERVICE);
updatePreferences();
handler.post(new Runnable() {
@Override public void run() {
Toast.makeText(getApplicationContext(), "Address:"+startAddress, Toast.LENGTH_LONG).show(); } });
}
public void updatePreferences() {
// sync local variables with preferences
android.util.Log.d("NWD", "updating preferences");
frequency = 10;
// update the LM with the new frequency
myLocationManager.removeUpdates(this);
myLocationManager.requestLocationUpdates(myLocationProvider.getName(),frequency, 0, this);
}
@Override
public void onDestroy() {
super.onDestroy();
/////------set edittext editable
android.util.Log.d("NWD", "destroying");
System.out.println("Inside on destroy of MWService");
myLocationManager.removeUpdates(this);
//myNotify("stopping");
InsertTripDetails_AsyncTask insert = new InsertTripDetails_AsyncTask();
insert.execute();
String provider = Settings.Secure.getString(getContentResolver(), Settings.Secure.LOCATION_PROVIDERS_ALLOWED);
if(provider.contains("gps")){ //if gps is enabled
final Intent poke = new Intent();
poke.setClassName("com.android.settings", "com.android.settings.widget.SettingsAppWidgetProvider");
poke.addCategory(Intent.CATEGORY_ALTERNATIVE);
poke.setData(Uri.parse("3"));
sendBroadcast(poke);
}
handler.removeCallbacks(sendUpdatesToUI);
}
@SuppressWarnings("deprecation")
@Override
public void onStart(Intent intent, int startId) {
super.onStart(intent, startId);
android.util.Log.d("NWD", "starting");
currentLocation = myLocationManager.getLastKnownLocation(myLocationProvider.getName());
//myNotify("starting");
handler.postDelayed(sendUpdatesToUI, 3000); // 1 sec
}
private Runnable sendUpdatesToUI = new Runnable() {
public void run() {
System.out.println("total_distance::"+total_distance);
intent.putExtra("distance",(total_distance/1000));
sendBroadcast(intent);
handler.postDelayed(this, 3000);
}
};
public void onProviderDisabled(String arg0) {
}
public void onProviderEnabled(String arg0) {
}
public void onStatusChanged(String arg0, int arg1, Bundle arg2) {
}
@Override
public IBinder onBind(Intent arg0) {
return null; // this is for heavy IPC, not used
}
private class InsertTripDetails_AsyncTask extends AsyncTask<String, Void, String> {
@Override
protected String doInBackground(String... urls) {
try {
try {
//InternetAvailable()
if(InternetAvailable()){
startAddress = geocoder.fetchCityName(getApplicationContext(),startLocation);
System.out.println("start address:"+startAddress);
endAddress = geocoder.fetchCityName(getApplicationContext(),endLocation);
System.out.println("end address:"+endAddress);
}else{
System.out.println("internet not available");
}
// Internet not available when data are store in latitude and longitute format
if(startAddress.equalsIgnoreCase("") && endAddress.equalsIgnoreCase("")){
DecimalFormat sd = new DecimalFormat("##.##");
System.out.println("1 lat:"+sd.format(startLocation.getLatitude()) +" long:"+sd.format(startLocation.getLongitude())+",lat:"+sd.format(endLocation.getLatitude()) +" long:"+sd.format(endLocation.getLongitude()));
}else if(startAddress.equalsIgnoreCase("")){
DecimalFormat sd = new DecimalFormat("##.##");
System.out.println("2 lat:"+sd.format(startLocation.getLatitude()) +" long:"+sd.format(startLocation.getLongitude())+","+endAddress);
}else if(endAddress.equalsIgnoreCase("")){
DecimalFormat sd = new DecimalFormat("##.##");
try {
System.out.println(startAddress+",3 lat:"+sd.format(endLocation.getLatitude()) +" long:"+sd.format(endLocation.getLongitude()));
} catch (Exception e) {
e.printStackTrace();
}
}
else{
System.out.println(startAddress+" "+ endAddress);
}
} catch (Exception e) {
e.printStackTrace();
}
} catch (Exception e) {
e.printStackTrace();
System.out.println("In catch of webservice thus no internet");
}
return "dfs";
}
@Override
protected void onPostExecute(String result) {
}
}
}
地理编码器类的代码
public class GeocoderHelper
{
private static final AndroidHttpClient ANDROID_HTTP_CLIENT = AndroidHttpClient.newInstance(GeocoderHelper.class.getName());
private String address="";
private Location i_Location;
private Context i_Context;
public String fetchCityName(final Context contex, final Location location)
{
i_Location = location;
i_Context = contex;
try {
return new Address().execute().get();
} catch (Exception e) {
return address;
}
}
public class Address extends AsyncTask<Void, Void, String>
{
@SuppressWarnings("unused")
@Override
protected String doInBackground(Void... params)
{
String cityName = null;
if (Geocoder.isPresent())
{
try
{
System.out.println("location latitude is"+i_Location.getLatitude());
System.out.println("location longitude is"+i_Location.getLongitude());
Geocoder geocoder = new Geocoder(i_Context, Locale.getDefault());
List<android.location.Address> addresses = geocoder.getFromLocation(i_Location.getLatitude(), i_Location.getLongitude(), 1);
if (addresses.size() > 0)
{
//cityName = addresses.get(0).getLocality();
address = addresses.get(0).getLocality();
System.out.println("geocoder inside present address is"+address);
}
}
catch (Exception ignored)
{
// after a while, Geocoder start to trhow "Service not availalbe" exception. really weird since it was working before (same device, same Android version etc..
}
}
if (cityName != null) // i.e., Geocoder succeed
{
return cityName;
}
else // i.e., Geocoder failed
{
return fetchCityNameUsingGoogleMap();
}
}
// Geocoder failed :-(
// Our B Plan : Google Map
private String fetchCityNameUsingGoogleMap()
{
try
{
String googleMapUrl = "http://maps.googleapis.com/maps/api/geocode/json?latlng=" + i_Location.getLatitude() + ","
+ i_Location.getLongitude() + "&sensor=false&language=fr";
JSONObject googleMapResponse = new JSONObject(ANDROID_HTTP_CLIENT.execute(new HttpGet(googleMapUrl),
new BasicResponseHandler()));
// many nested loops.. not great -> use expression instead
// loop among all results
JSONArray results = (JSONArray) googleMapResponse.get("results");
for (int i = 0; i < results.length(); i++)
{
// loop among all addresses within this result
JSONObject result = results.getJSONObject(i);
address = result.getString("formatted_address");
System.out.println("map address:"+address);
break;
/* if (result.has("address_components"))
{
JSONArray addressComponents = result.getJSONArray("address_components");
// loop among all address component to find a 'locality' or 'sublocality'
for (int j = 0; j < addressComponents.length(); j++)
{
JSONObject addressComponent = addressComponents.getJSONObject(j);
if (result.has("types"))
{
JSONArray types = addressComponent.getJSONArray("types");
// search for locality and sublocality
String cityName = null;
String ROUTE= null;
for (int k = 0; k < types.length(); k++)
{
if ("locality".equals(types.getString(k)) && cityName == null)
{
if (addressComponent.has("long_name"))
{
cityName = addressComponent.getString("long_name");
}
else if (addressComponent.has("short_name"))
{
cityName = addressComponent.getString("short_name");
}
}
if ("sublocality".equals(types.getString(k)))
{
if (addressComponent.has("long_name"))
{
cityName = addressComponent.getString("long_name");
}
else if (addressComponent.has("short_name"))
{
cityName = addressComponent.getString("short_name");
}
}
}
if (cityName != null)
{
address = cityName;
return cityName;
}
}
}
}*/
}
}
catch (Exception ignored)
{
ignored.printStackTrace();
}
return address;
}
protected void onPostExecute(String result)
{
super.onPostExecute(result);
}
}
}
MAinActivity 类的代码
public class MainActivity extends Activity {
//private final Handler handler = new Handler();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
startService(new Intent(MainActivity.this,MWService.class));
}
@Override
protected void onPause() {
super.onPause();
stopService(new Intent(MainActivity.this,MWService.class));
}
}
我在我的清单文件中拥有 Internet 和 AccessFineLocation 的使用权限
我的logcat味精.....
10-31 13:40:41.937: ERROR/AndroidRuntime(825): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.example.address2/com.example.android.MainActivity}: java.lang.ClassNotFoundException: com.example.android.MainActivity in loader dalvik.system.PathClassLoader[/data/app/com.example.address2-1.apk]
10-31 13:40:41.937: ERROR/AndroidRuntime(825): Caused by: java.lang.ClassNotFoundException: com.example.android.MainActivity in loader dalvik.system.PathClassLoader[/data/app/com.example.address2-1.apk]
我的清单文件的代码....
<uses-sdk
android:minSdkVersion="10"
android:targetSdkVersion="17" />
<uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name="com.example.android.MainActivity"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<service android:name="MWService"></service>
</application>