我收到NullPointerException，这是我的日志：
05-23 00:42:49.384: E/AndroidRuntime(408): FATAL EXCEPTION: main
05-23 00:42:49.384: E/AndroidRuntime(408): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.apparkingit/com.example.apparkingit.MainActivity}: java.lang.NullPointerException
05-23 00:42:49.384: E/AndroidRuntime(408): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1736)
05-23 00:42:49.384: E/AndroidRuntime(408): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1752)
05-23 00:42:49.384: E/AndroidRuntime(408): at android.app.ActivityThread.access$1500(ActivityThread.java:123)
05-23 00:42:49.384: E/AndroidRuntime(408): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:993)
05-23 00:42:49.384: E/AndroidRuntime(408): at android.os.Handler.dispatchMessage(Handler.java:99)
05-23 00:42:49.384: E/AndroidRuntime(408): at android.os.Looper.loop(Looper.java:126)
05-23 00:42:49.384: E/AndroidRuntime(408): at android.app.ActivityThread.main(ActivityThread.java:3997)
05-23 00:42:49.384: E/AndroidRuntime(408): at java.lang.reflect.Method.invokeNative(Native Method)
05-23 00:42:49.384: E/AndroidRuntime(408): at java.lang.reflect.Method.invoke(Method.java:491)
05-23 00:42:49.384: E/AndroidRuntime(408): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:841)
05-23 00:42:49.384: E/AndroidRuntime(408): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:599)
05-23 00:42:49.384: E/AndroidRuntime(408): at dalvik.system.NativeStart.main(Native Method)
05-23 00:42:49.384: E/AndroidRuntime(408): Caused by: java.lang.NullPointerException
05-23 00:42:49.384: E/AndroidRuntime(408): at com.example.apparkingit.MainActivity.onCreate(MainActivity.java:83)
05-23 00:42:49.384: E/AndroidRuntime(408): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1048)
05-23 00:42:49.384: E/AndroidRuntime(408): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1700)
05-23 00:42:49.384: E/AndroidRuntime(408): ... 11 more
这是我的MainActivity代码：
public class MainActivity extends FragmentActivity {
GoogleMap googleMap;
MarkerOptions markerOptions;
LatLng latLng;
private ProgressDialog pDialog;
//private ListView navList;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Getting reference to SupportMapFragment
SupportMapFragment fragment = (SupportMapFragment) getSupportFragmentManager()
.findFragmentById(R.id.map);
// Getting reference to btn_find of the layout activity_main
Button btn_find = (Button) findViewById(R.id.btn_find);
OnClickListener findClickListener = new OnClickListener() {
@Override
public void onClick(View v) {
// Getting reference to EditText to get the user input location
EditText etLocation = (EditText) findViewById(R.id.et_location);
// Getting user input location
String location = etLocation.getText().toString();
if(location!=null && !location.equals("")){
new GeocoderTask().execute(location);
}
}
};
btn_find.setOnClickListener(findClickListener);
// Creating GoogleMap from SupportMapFragment
googleMap = fragment.getMap();
// Enabling MyLocation button for the Google Map
googleMap.setMyLocationEnabled(true);
double lat= -33.4520839;
double lng = -70.6585019;
LatLng ll = new LatLng(lat, lng);
googleMap.moveCamera(CameraUpdateFactory.newLatLngZoom(ll, 10));
googleMap.setOnMyLocationChangeListener(new GoogleMap.OnMyLocationChangeListener() {
Integer sw=1;
public void onMyLocationChange(Location pos) {
// TODO Auto-generated method stub
if (sw==1){
// Extraigo la Lat y Lon del Listener
final double latO2 = pos.getLatitude();
final double lonO2 = pos.getLongitude();
sw=0;
}
}
});
googleMap.setOnInfoWindowClickListener(new GoogleMap.OnInfoWindowClickListener() {
@Override
public void onInfoWindowClick(Marker marker) {
// TODO Auto-generated method stub
// Obtenemos la posicion del marcador en tipo LatLng
String snip = marker.getSnippet();
Location Origen = googleMap.getMyLocation();
double Origenlat = Origen.getLatitude();
double Origenlng = Origen.getLongitude();
LatLng LatLng = marker.getPosition();
double latt = LatLng.latitude;
double lngg = LatLng.longitude;
String user;
String lat = Double.toString(latt);
String lng = Double.toString(lngg);
String latO = Double.toString(Origenlat);
String lngO = Double.toString(Origenlng);
Bundle bundle = getIntent().getExtras();
user = bundle.getString("user");//usuario
String title = marker.getTitle();
if (snip.equalsIgnoreCase("Estacionamiento")==true){
Intent i = new Intent(MainActivity.this,infowindow.class);
i.putExtra("latO", latO);
i.putExtra("lngO", lngO);
i.putExtra("title", title);
i.putExtra("lat", lat);
i.putExtra("lng", lng);
i.putExtra("user", user);
Log.e("Variable a pasar",lat);
Log.e("Variable a pasar",lng);
Log.e("Variable a pasar",title);
Log.e("Variable a pasar",latO);
Log.e("Variable a pasar",lngO);
startActivity(i);
}
if (snip.equalsIgnoreCase("Bencinera")==true){
Intent i = new Intent(MainActivity.this,infowindowben.class);
i.putExtra("latO", latO);
i.putExtra("lngO", lngO);
i.putExtra("title", title);
i.putExtra("lat", lat);
i.putExtra("lng", lng);
Log.e("Variable a pasar",lat);
Log.e("Variable a pasar",lng);
Log.e("Variable a pasar",title);
Log.e("Variable a pasar",latO);
Log.e("Variable a pasar",lngO);
startActivity(i);
}
// startActivity(new Intent(MainActivity.this,infowindow.class));
}
});
// Setting OnClickEvent listener for the GoogleMap
//mGoogleMap.setOnMapClickListener(new OnMapClickListener() {
//@Override
//public void onMapClick(LatLng latlng) {
// addMarker(latlng);
// sendToServer(latlng);
//}
// });
// Starting locations retrieve task
new RetrieveTask().execute();
googleMap.setOnMyLocationChangeListener(new GoogleMap.OnMyLocationChangeListener() {
Integer sw=1;
public void onMyLocationChange(Location pos) {
// TODO Auto-generated method stub
if (sw==1){
// Extraigo la Lat y Lon del Listener
double lat = pos.getLatitude();
double lon = pos.getLongitude();
LatLng Punto = new LatLng(lat,lon);
MarkerOptions mp = new MarkerOptions();
mp.position(new LatLng(lat, lon));
mp.title("my position");
mp.icon(BitmapDescriptorFactory.fromResource(R.drawable.markergeolocx));
googleMap.addMarker(mp);
// Muevo la cámara a mi posición
CameraUpdate cam = CameraUpdateFactory.newLatLngZoom(Punto, 10);
sw=0;
}
}
});
final AlertDialog alert = null;
final LocationManager manager = (LocationManager) getSystemService( Context.LOCATION_SERVICE );
if ( !manager.isProviderEnabled( LocationManager.GPS_PROVIDER ) ) {
AlertNoGps();}
}
private void AlertNoGps() {
final AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setMessage("El sistema GPS debe estar activado para que funcione la App correctamente, ¿Desea activarlo?")
.setCancelable(false)
.setPositiveButton("Si", new DialogInterface.OnClickListener() {
public void onClick(@SuppressWarnings("unused") final DialogInterface dialog, @SuppressWarnings("unused") final int id) {
startActivity(new Intent(android.provider.Settings.ACTION_LOCATION_SOURCE_SETTINGS));
}
})
.setNegativeButton("No", new DialogInterface.OnClickListener() {
public void onClick(final DialogInterface dialog, @SuppressWarnings("unused") final int id) {
dialog.cancel();
}
});
AlertDialog alert = builder.create();
alert.show();
}
// FIN DEL ONCREATE
// Adding marker on the GoogleMaps
private void addMarker(LatLng latlng, String title , String categoria) {
MarkerOptions markerOptions = new MarkerOptions();
markerOptions.position(latlng);
markerOptions.title(title);
markerOptions.snippet(categoria);
if (categoria.equalsIgnoreCase("Estacionamiento")==true){
markerOptions.icon(BitmapDescriptorFactory.fromResource(R.drawable.markerestx));
}
if (categoria.equalsIgnoreCase("Bencinera")==true){
markerOptions.icon(BitmapDescriptorFactory.fromResource(R.drawable.markerbenx));
}
if (categoria.equalsIgnoreCase("Bicicleta")==true){
markerOptions.icon(BitmapDescriptorFactory.fromResource(R.drawable.markerbicix));
}
if (categoria.equalsIgnoreCase("Servipag")==true){
markerOptions.icon(BitmapDescriptorFactory.fromResource(R.drawable.markersenx));
}
googleMap.addMarker(markerOptions);
}
// Invoking background thread to store the touched location in Remove MySQL server
//// new SaveTask().execute(latlng);
//}
// Background task to retrieve locations from remote mysql server
private class RetrieveTask extends AsyncTask<Void, Void, String>{
@Override
protected String doInBackground(Void... params) {
String strUrl = "http://biosis1.comlu.com/retrieve4.php";
URL url = null;
StringBuffer sb = new StringBuffer();
try {
url = new URL(strUrl);
HttpURLConnection connection = (HttpURLConnection) url.openConnection();
connection.connect();
InputStream iStream = connection.getInputStream();
BufferedReader reader = new BufferedReader(new InputStreamReader(iStream));
String line = "";
while( (line = reader.readLine()) != null){
sb.append(line);
}
reader.close();
iStream.close();
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return sb.toString();
}
@Override
protected void onPostExecute(String result) {
super.onPostExecute(result);
new ParserTask().execute(result);
}
}
// Background thread to parse the JSON data retrieved from MySQL server
private class ParserTask extends AsyncTask<String, Void, List<HashMap<String, String>>>{
protected void onPreExecute() {
//para el progress dialog
pDialog = new ProgressDialog(MainActivity.this);
pDialog.setMessage("Cargando Mapa...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(false);
pDialog.show();
}
@Override
protected List<HashMap<String,String>> doInBackground(String... params) {
MarkerJSONParser markerParser = new MarkerJSONParser();
JSONObject json = null;
try {
json = new JSONObject(params[0]);
} catch (JSONException e) {
e.printStackTrace();
}
List<HashMap<String, String>> markersList = markerParser.parse(json);
return markersList;
}
@Override
protected void onPostExecute(List<HashMap<String, String>> result) {
try{
for(int i=0; i<result.size();i++){
HashMap<String, String> marker = result.get(i);
String categoria = marker.get("categoria");
LatLng latlng = new LatLng(Double.parseDouble(marker.get("lat")), Double.parseDouble(marker.get("lng")));
String title = marker.get("title");
Log.e("Valor",categoria);
addMarker(latlng,title,categoria);
}
pDialog.dismiss();
Toast.makeText(getBaseContext(), "Mapa cargado correctamente!", Toast.LENGTH_SHORT).show();
}catch (Exception e){
Toast.makeText(getBaseContext(), e.getMessage(), Toast.LENGTH_LONG).show() ;
}
}
}
//@Override
//public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
//().inflate(R.menu.main, menu);
// return true;
//}
// An AsyncTask class for accessing the GeoCoding Web Service
private class GeocoderTask extends AsyncTask<String, Void, List<Address>>{
@Override
protected List<Address> doInBackground(String... locationName) {
// Creating an instance of Geocoder class
Geocoder geocoder = new Geocoder(getBaseContext());
List<Address> addresses = null;
try {
// Getting a maximum of 3 Address that matches the input text
addresses = geocoder.getFromLocationName(locationName[0], 3);
} catch (IOException e) {
e.printStackTrace();
}
return addresses;
}
@Override
protected void onPostExecute(List<Address> addresses) {
if(addresses==null || addresses.size()==0){
Toast.makeText(getBaseContext(), "No se ha encontrado direccion", Toast.LENGTH_SHORT).show();
}
// Clears all the existing markers on the map
//googleMap.clear();
// Adding Markers on Google Map for each matching address
for(int i=0;i<addresses.size();i++){
Address address = (Address) addresses.get(i);
// Creating an instance of GeoPoint, to display in Google Map
latLng = new LatLng(address.getLatitude(), address.getLongitude());
String addressText = String.format("%s, %s",
address.getMaxAddressLineIndex() > 0 ? address.getAddressLine(0) : "",
address.getCountryName());
markerOptions = new MarkerOptions();
markerOptions.position(latLng);
markerOptions.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_GREEN));
markerOptions.title(addressText);
// googleMap.addMarker(markerOptions);
// Locate the first location
if(i==0)
googleMap.animateCamera(CameraUpdateFactory.newLatLngZoom(latLng,15));
}
}
}
}
这是我的XML：
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context=".MainActivity" >
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="horizontal" >
<Button
android:id="@+id/btn_find"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/str_btn_find"
android:layout_alignParentRight="true" />
<EditText
android:id="@+id/et_location"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:inputType="text"
android:hint="@string/hnt_et_location"
android:layout_toLeftOf="@id/btn_find" />
</LinearLayout>
<fragment
android:id="@+id/map"
android:layout_width="match_parent"
android:layout_height="match_parent"
class="com.google.android.gms.maps.SupportMapFragment" />
</LinearLayout>
问题是该应用程序刚刚与Android版本＆gt; 4.0崩溃，我真的不知道我该怎么做：（
这是我的第一个问题，所以我很抱歉代码的错误结构。
谢谢！