我们正在使用Android应用程序，第一页是启动画面，后一页是谷歌地图。这个谷歌地图活动使应用程序停止在一些Android手机，如Android版本4.4.2。但在一些Android手机中它运行正常。谷歌地图是否对android API有一些限制。
在4.4.2版本的Android版本中运行时。它显示了这个错误。
java.lang.RuntimeException: Unable to start activity ComponentInfo{salon.com.barber/salon.com.barber.GoogleMapsActivity}: java.lang.NullPointerException
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2342)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2392)
at android.app.ActivityThread.access$800(ActivityThread.java:151)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1266)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:136)
at android.app.ActivityThread.main(ActivityThread.java:5421)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:970)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:786)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.NullPointerException
at salon.com.barber.GoogleMapsActivity.populateMap(GoogleMapsActivity.java:287)
at salon.com.barber.GoogleMapsActivity.onCreate(GoogleMapsActivity.java:205)
at android.app.Activity.performCreate(Activity.java:5263)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1099)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2282)
... 11 more
我的Google地图活动
public class GoogleMapsActivity extends FragmentActivity {
ImageButton imageButton;
NavDrawerListAdapterSalonDetails adapternav;
DrawerLayout dLayout;
List<NavDrawerSalonDetailsItem> menu;
private ProgressDialog pDialog;
ListView dList1;
private GoogleMap mMap;
GPSTracker gps;
boolean isGpsON;
ArrayList<String> arry_salondetails;
String SaloonDetails = "";
String Street = null;
String Zipcode = null;
String HouseNumber = null;
String City = null;
//final ArrayList<String> SalonNames = new ArrayList<String>();
final HashMap SalonData = new HashMap();
double lati,longi;
final ArrayList<String> serviceDataList = new ArrayList<String>();
Boolean isInternetPresent;
JSONObject objectNextClass;
private GoogleMap googleMap;
JSONArray saloonDetails = null;
RelativeLayout selectedLayout;
double latitude, longitude, range;
String tableName = "barber";
Marker selectedMarker;
ImageButton button_bookmark ;
String objectId = "";
public static final String BARBER_MAP_PREFS = "MAP_PREFS";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_google_maps);
selectedLayout = (RelativeLayout) findViewById(R.id.selectedView);
networkCheck cd = new networkCheck(getApplicationContext());
isInternetPresent = cd.isConnectingToInternet(); // true or
// false
Log.i("sfeeee", "wwwwwww111w");
SharedPreferences prefs = getSharedPreferences(BARBER_MAP_PREFS, MODE_PRIVATE);
String r = prefs.getString("range", null);
if (r == null) {
SharedPreferences.Editor editor = prefs.edit();
editor.putString("range", "10");
editor.commit();
}
AndroidLog.appendLog("En:2");
imageButton =(ImageButton) findViewById(R.id.Search_btn);
imageButton.setOnClickListener(new View.OnClickListener() {
@Override
// On click function
public void onClick(View view) {
// Create the intent to start another activity
Log.i("sfeeee1111111", "wwwwwwww");
Intent i = new Intent(GoogleMapsActivity.this, Search.class);
startActivity(i);
}
});
AndroidLog.appendLog("Ex:2");
dLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
dList1 = (ListView) findViewById(R.id.list_slidermenu);
menu = getNavDraweItemList();
adapternav = new NavDrawerListAdapterSalonDetails(this, menu);
LayoutInflater inflater=this.getLayoutInflater();
View header=inflater.inflate(R.layout.footer, null);
dList1.addHeaderView(header);
dList1.setAdapter(adapternav);
ImageButton buttonMenu =((ImageButton) findViewById(R.id.buttonMenu));
dList1.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
getListPosition(position);
// TODO Auto-generated method stub
}
});
buttonMenu.setOnClickListener(new View.OnClickListener() {
@Override
// On click function
public void onClick(View view) {
dLayout.openDrawer(dList1);
}
});
ImageButton button_map=(ImageButton) findViewById(R.id.button_map);
Log.i("111111111111111", "qqqqqqqqqqqqq");
button_map.setOnClickListener(new View.OnClickListener() {
@Override
// On click function
public void onClick(View view) {
// Create the intent to start another activity
if (isInternetPresent) {
LatLng myCurrentLoc = getCurrentLoaction();
Log.i("mycurrentLoc", myCurrentLoc.toString());
Log.i("2222222222211", "qqqqqqqqqqqqq");
mMap.moveCamera(CameraUpdateFactory.newLatLngZoom(
(myCurrentLoc), 11));
Log.i("3333333333333331", "qqqqqqqqqqqqq");
}
}
});
AndroidLog.appendLog("En:3");
if (isInternetPresent) {
// Calling async task to get json
//new getLocationData().execute();
populateMap();
AndroidLog.appendLog("Ex:3");
Log.i("4444444411111", "qqqqqqqqqqqqq");
} else {
// Internet connection not present
// Ask user to connect to Internet
showAlertDialog(GoogleMapsActivity.this, "No Internet Connection",
"You don't have internet connection.", false);
}
selectedLayout.setVisibility(View.GONE);
Button button = ((Button) selectedLayout
.findViewById(R.id.selec_button_id));
button.setOnClickListener(new View.OnClickListener() {
@Override
// On click function
public void onClick(View view) {
// Create the intent to start another activity
Intent intent = new Intent(view.getContext(),
Salon_Detail.class);
//intent.putExtra("SalonName", (CharSequence) nameView);
// intent.putExtra("json", objectNextClass.toString());
startActivity(intent);
}
});
}
public void onDestroy() {
super.onDestroy();
SharedPreferences prefs = getSharedPreferences(BARBER_MAP_PREFS, MODE_PRIVATE);
SharedPreferences.Editor editor = prefs.edit();
editor.clear();
}
public void populateMap(){
Log.d("searched", "map");
pDialog = new ProgressDialog(GoogleMapsActivity.this);
pDialog.setMessage("Please wait...");
pDialog.setCancelable(false);
pDialog.show();
if (mMap == null) {
mMap = ((MapFragment) getFragmentManager()
.findFragmentById(R.id.map)).getMap();
}
LatLng myCurrentLoc = getCurrentLoaction();
if(!isGpsON)
{
Toast.makeText(getApplicationContext(),"Switch on the location service for more accuracy",
30000).show();
}
Log.i("Latti and Longii", myCurrentLoc.toString());
latitude = myCurrentLoc.latitude;
Log.i("latitude of current Loc", String.valueOf(latitude));
longitude = myCurrentLoc.longitude;
Log.i("longitudeofcurrent Loc",String.valueOf(longitude));
mMap.addCircle(new CircleOptions()
.center(new LatLng(myCurrentLoc.latitude,
myCurrentLoc.longitude)).radius(10000)
.strokeColor(Color.parseColor("#34DDDD")).strokeWidth(6.0f)
.fillColor(Color.parseColor("#93D5E4")));
Log.i("777777777777777", "qqqqqqqqqqqqq");
mMap.moveCamera(CameraUpdateFactory.newLatLngZoom(
(myCurrentLoc), 11));
Log.i("666666666666666666", "qqqqqqqqqqqqq");
Marker TP = mMap.addMarker(new MarkerOptions().position(
myCurrentLoc).title("").icon(BitmapDescriptorFactory.fromResource(R.mipmap.pin_blue)));
//icon(BitmapDescriptorFactory.fromResource(R.drawable.navigate))
TP.showInfoWindow();
Log.i("5555555555555555555555", "qqqqqqqqqqqqq");
TP.setSnippet("currentLocation");
SharedPreferences prefs = getSharedPreferences(BARBER_MAP_PREFS, MODE_PRIVATE);
range = Double.parseDouble(prefs.getString("range",null));
//range = 100;
new GmapUtil().onGetCustomMarkers(getApplicationContext(), longitude, latitude, range, tableName,
new GmapUtil.CustomMarker() {
@Override
public void onSuccess(String data) {
Log.i("resulttttttt od dataaa", data);
pDialog.hide();
try {
JSONObject jsonObject = new JSONObject(data);
Log.i("jsonObjectttttttttttt", jsonObject.toString());
JSONObject jsonObject1 = jsonObject.getJSONObject("data");
Log.i("jsonObjecttttttt1", jsonObject1.toString());
JSONArray jsonArray = jsonObject1.getJSONArray("results");
for (int i = 0; i < jsonArray.length(); i++) {
final JSONObject child = jsonArray.getJSONObject(i);
//final String sName = child.getString("SalonName");
//SalonNames.add(child.getString("SalonName"));
//Log.i("salonn namesss", SalonNames.toString());
latitude = child.getDouble("Latitude");
longitude = child.getDouble("Longitude");
LatLng saloonLoc = new LatLng(latitude, longitude);
mMap.setMapType(GoogleMap.MAP_TYPE_NORMAL);
Marker marker = mMap.addMarker(new MarkerOptions()
.position(saloonLoc).title("TutorialsPoint").icon(BitmapDescriptorFactory.fromResource(R.mipmap.map_red)));
marker.setSnippet(child.getString("objectId"));
SalonData.put(child.getString("objectId"), child);
Log.i("8888888888888888", "qqqqqqqqqqqqq");
// googleMap.setOnMarkerClickListener(this);
mMap.setOnMarkerClickListener(new GoogleMap.OnMarkerClickListener() {
@Override
public boolean onMarkerClick(Marker marker) {
SaloonDetails = "";
// Take some action here
String snippet = marker.getSnippet();
objectId = snippet;
if (selectedMarker != null && !("currentLocation".equals(snippet))) {
selectedMarker.setIcon(BitmapDescriptorFactory.fromResource(R.mipmap.map_red));
}
selectedMarker = marker;
if (!("currentLocation".equals(snippet)))
marker.setIcon(BitmapDescriptorFactory.fromResource(R.mipmap.map_blue));
Log.i("TAG", "snippet::::" + snippet);
if ("currentLocation".equals(snippet)) {
selectedLayout.setVisibility(View.GONE);
//button_bookmark.setVisibility(View.GONE);
return false;
} else {
selectedLayout
.setVisibility(View.VISIBLE);
TextView nameView = ((TextView) selectedLayout
.findViewById(R.id.name_txt_id));
TextView addressView = ((TextView) selectedLayout
.findViewById(R.id.address_txt_id));
try {
JSONObject jSalonData = (JSONObject)SalonData.get(snippet);
nameView.setText(jSalonData.getString("SalonName"));
} catch (Exception e) {
e.printStackTrace();
}
try {
JSONObject jSalonData = (JSONObject)SalonData.get(snippet);
Log.i("jSalonData",jSalonData.toString());
//addressView.append(System.getProperty("line.separator"));
City = jSalonData.optString("City");
SaloonDetails = SaloonDetails + City;
Zipcode = jSalonData.optString("Zipcode");
SaloonDetails = SaloonDetails +" "+ Zipcode;
HouseNumber = jSalonData.optString("HouseNumber");
SaloonDetails = SaloonDetails +" "+ HouseNumber;
Street = jSalonData.optString("Street");
SaloonDetails = SaloonDetails +" "+ Street;
Log.i("SaloonDetails", SaloonDetails);
//addressView.setText(jSalonData.getString("Zipcode"));
//addressView.setText(jSalonData.getString("City"));
addressView.setText(SaloonDetails);
} catch (Exception e) {
e.printStackTrace();
}
return true;
}
}
});
}
} catch (Exception e) {
Log.i("Exception", e.toString());
}
}
@Override
public void onError(String data) {
}
});
}
private LatLng getCurrentLoaction() {
// TODO Auto-generated method stub
Log.i("sfeeee","wwwwwwww");
gps = new GPSTracker(GoogleMapsActivity.this);
// check if GPS enabled
if (gps.canGetLocation()) {
isGpsON=true;
double latitude = gps.getLatitude();
double longitude = gps.getLongitude();
LatLng latLng = new LatLng(latitude, longitude);
Log.i("Latiiiiiiiiii",latLng.toString());
return latLng;
// \n is for new line
} else {
// can't get location
// GPS or Network is not enabled
// Ask user to enable GPS/network in settings
isGpsON=false;
LatLng latLng = new LatLng(52.156111,5.387827);
return latLng;
}
}
private List<NavDrawerSalonDetailsItem> getNavDraweItemList() {
String search = "Search";
String Privacypolicy = "Privacy policy";
String termsofconditions = "Terms and Conditions";
String favorite = " Favourites";
String Setting = "Settings";
String[] list = new String[] {search, Privacypolicy,termsofconditions,favorite,Setting};
int[] icons = { R.mipmap.small_search, R.mipmap.small_about_us };
List<NavDrawerSalonDetailsItem> menu = new ArrayList<NavDrawerSalonDetailsItem>();
for (int i = 0; i < list.length; i++) {
menu.add(new NavDrawerSalonDetailsItem(list[i], i));
}
return menu;
}
/**
* Function to display simple Alert Dialog
*
* @param context
* - application context
* @param title
* - alert dialog title
* @param message
* - alert message
* @param status
* - success/failure (used to set icon)
* */
@SuppressWarnings("deprecation")
public void showAlertDialog(Context context, String title, String message,
Boolean status) {
AlertDialog alertDialog = new AlertDialog.Builder(context).create();
// Setting Dialog Title
alertDialog.setTitle(title);
// Setting Dialog Message
alertDialog.setMessage(message);
// Setting OK Button
alertDialog.setButton("OK", new DialogInterface.OnClickListener() {
public void onClick(final DialogInterface dialog, final int which) {
}
});
// Showing Alert Message
alertDialog.show();
}
public void search(){
// Create the intent to start another activity
Intent intent = new Intent(GoogleMapsActivity.this, Search.class);
startActivity(intent);
}
public void privacyPolicy(){
// Create the intent to start another activity
Intent intent = new Intent(GoogleMapsActivity.this, privacypolicy.class);
startActivity(intent);
}
public void termsAndCondition(){
// Create the intent to start another activity
Intent intent = new Intent(GoogleMapsActivity.this, Terms_and_condition.class);
startActivity(intent);
}
public void favorite(){
Intent intent = new Intent(GoogleMapsActivity.this,comingsoon.class);
startActivity(intent);
}
public void Settings(){
Intent intent = new Intent(GoogleMapsActivity.this,comingsoon.class);
startActivity(intent);
}
public void getListPosition(int position) {
switch (position) {
case 1: {
search();
break;
}
case 2: {
privacyPolicy();
break;
}
case 3: {
termsAndCondition();
break;
}
case 4: {
favorite();
break;
}
case 5: {
Settings();
break;
}
default: {
break;
}
}
}
}
答案 0 :(得分：2)
要确保您使用的是GoogleMap的非null实例，您应该实现OnMapReadyCallback。来自文档https://developers.google.com/android/reference/com/google/android/gms/maps/OnMapReadyCallback
在MapFragment或MapView对象上设置此接口的实例后，当地图准备好使用时会触发onMapReady（GoogleMap）方法并提供GoogleMap的非空实例。
因此，您的GoogleMapsActivity需要实施OnMapReadyCallback，您必须将调用populateMap();方法转移到onMapReady方法：
public class GoogleMapsActivity extends FragmentActivity implements OnMapReadyCallback {
// ...
@Override
protected void onCreate(Bundle savedInstanceState) {
// Remove populateMap(); and change it for
((MapFragment) getFragmentManager()
.findFragmentById(R.id.map)).getMapAsync(this);
}
@Override
public void onMapReady(GoogleMap googleMap) {
mMap = googleMap;
populateMap();
}
}