Does the geocoder work on emulators

问题

I am using the geocoder and it worked just fine on my device but not working on emulators tried it on 2.2 and 4.2.2 didn't work;

this is my code:

Geocoder myLocation = new Geocoder(AzanTime.this, Locale.getDefault());
List<Address> myList=null;
try {
    myList = myLocation.getFromLocation(latitude,longitude, 1);
} catch (IOException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
}
Address address = (Address) myList.get(0);
String addressStr = "";
if(address.getAddressLine(0)!=null){
    addressStr += address.getAddressLine(0);

}

And the logcat:

01-11 09:31:07.573: E/AndroidRuntime(788): FATAL EXCEPTION: main
01-11 09:31:07.573: E/AndroidRuntime(788): java.lang.RuntimeException: Unable to start activity ComponentInfo{amina.myhomebusiness.IslamicApps.FortressOfTheMuslimExplanation/amina.myhomebusiness.IslamicApps.FortressOfTheMuslimExplanation.AzanTime}: java.lang.IllegalArgumentException: provider doesn't exisit: null
01-11 09:31:07.573: E/AndroidRuntime(788):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2180)
01-11 09:31:07.573: E/AndroidRuntime(788):  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2230)
01-11 09:31:07.573: E/AndroidRuntime(788):  at android.app.ActivityThread.access$600(ActivityThread.java:141)
01-11 09:31:07.573: E/AndroidRuntime(788):  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1234)
01-11 09:31:07.573: E/AndroidRuntime(788):  at android.os.Handler.dispatchMessage(Handler.java:99)
01-11 09:31:07.573: E/AndroidRuntime(788):  at android.os.Looper.loop(Looper.java:137)
01-11 09:31:07.573: E/AndroidRuntime(788):  at android.app.ActivityThread.main(ActivityThread.java:5041)
01-11 09:31:07.573: E/AndroidRuntime(788):  at java.lang.reflect.Method.invokeNative(Native Method)
01-11 09:31:07.573: E/AndroidRuntime(788):  at java.lang.reflect.Method.invoke(Method.java:511)
01-11 09:31:07.573: E/AndroidRuntime(788):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
01-11 09:31:07.573: E/AndroidRuntime(788):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
01-11 09:31:07.573: E/AndroidRuntime(788):  at dalvik.system.NativeStart.main(Native Method)
01-11 09:31:07.573: E/AndroidRuntime(788): Caused by: java.lang.IllegalArgumentException: provider doesn't exisit: null
01-11 09:31:07.573: E/AndroidRuntime(788):  at android.os.Parcel.readException(Parcel.java:1429)
01-11 09:31:07.573: E/AndroidRuntime(788):  at android.os.Parcel.readException(Parcel.java:1379)
01-11 09:31:07.573: E/AndroidRuntime(788):  at android.location.ILocationManager$Stub$Proxy.requestLocationUpdates(ILocationManager.java:538)
01-11 09:31:07.573: E/AndroidRuntime(788):  at android.location.LocationManager.requestLocationUpdates(LocationManager.java:836)
01-11 09:31:07.573: E/AndroidRuntime(788):  at android.location.LocationManager.requestLocationUpdates(LocationManager.java:430)

01-11 09:31:07.573: E/AndroidRuntime(788):  at android.app.Activity.performCreate(Activity.java:5104)
01-11 09:31:07.573: E/AndroidRuntime(788):  at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1080)
01-11 09:31:07.573: E/AndroidRuntime(788):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2144)
01-11 09:31:07.573: E/AndroidRuntime(788):  ... 11 more

回答1:

There is no Geocoder installed on emulators. Accroding to Geocoder reference

The Geocoder class requires a backend service that is not included in the core android framework. The Geocoder query methods will return an empty list if there no backend service in the platform. Use the isPresent() method to determine whether a Geocoder implementation exists.

You should have checked

Geocoder.isPresent()

Before accessing the API. It's more reliable to use your own implementation. Check this answer for my implementation. problems with android.location.geocoder

来源：https://stackoverflow.com/questions/21061175/does-the-geocoder-work-on-emulators