Geocoder.getFromLocationName方法出錯

Question

我試圖通過傳遞街道地址來使用地理編碼來獲取給定地點的緯度/經度。 這是我的代碼：

 String addr = "Shop No. 2, Payal Cinema, Old Delhi Road, Sec-14, Gurgaon";                             
 Geocoder geocoder= new Geocoder(this, Locale.getDefault());
 List<Address> addressList = null;
 try {

          addressList = geocoder.getFromLocationName(addr, 10);

     } catch (IOException e) {}
 Address address = addressList.get(0);
 if(address.hasLatitude() && address.hasLongitude()){
 lat = address.getLatitude();
 lon = address.getLongitude();
 }                   

錯誤發生在對gecoder.getFromLocationName（addr，10）的調用中（我通過System.out.println檢查了它;在該行之后沒有打印到logcat）

這是LogCat的堆棧跟蹤：

 W/dalvikvm(630): threadid=1: thread exiting with uncaught exception (group=0x409c01f8)
 E/AndroidRuntime(630): FATAL EXCEPTION: main
 E/AndroidRuntime(630): java.lang.RuntimeException: Unable to start activity ComponentInfo{apt.kangkan/apt.kangkan.AddrMarkrsonMapActivity}: java.lang.NullPointerException
 E/AndroidRuntime(630):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1956)
 E/AndroidRuntime(630):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1981)
 E/AndroidRuntime(630):     at android.app.ActivityThread.access$600(ActivityThread.java:123)
 E/AndroidRuntime(630):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1147)
 E/AndroidRuntime(630):     at android.os.Handler.dispatchMessage(Handler.java:99)
 E/AndroidRuntime(630):     at android.os.Looper.loop(Looper.java:137)
 E/AndroidRuntime(630):     at android.app.ActivityThread.main(ActivityThread.java:4424)
 E/AndroidRuntime(630):     at java.lang.reflect.Method.invokeNative(Native Method)
 E/AndroidRuntime(630):     at java.lang.reflect.Method.invoke(Method.java:511)
 E/AndroidRuntime(630):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
 E/AndroidRuntime(630):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
 E/AndroidRuntime(630):     at dalvik.system.NativeStart.main(Native Method)
 E/AndroidRuntime(630): Caused by: java.lang.NullPointerException
 E/AndroidRuntime(630):     at apt.kangkan.AddrMarkrsonMapActivity.onCreate(AddrMarkrsonMapActivity.java:76)
 E/AndroidRuntime(630):     at android.app.Activity.performCreate(Activity.java:4465)
 E/AndroidRuntime(630):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1049)
 E/AndroidRuntime(630):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1920)
 E/AndroidRuntime(630):     ... 11 more
 I/dalvikvm(630): threadid=3: reacting to signal 3
 I/dalvikvm(630): Wrote stack traces to '/data/anr/traces.txt'

你可以看到有一個java.lang.NullPointerException。 我不知道它為什么會產生。 請幫忙。

Answer 1

實際上沒有找到你的地址的緯度和經度請檢查“addressList”是否為null，如果它不為null，則繼續如下所示..

 if (addressList == null)
    {
             Log.d(TAG,"Latitude and longitude not found");
    }
     else {
     Address location = addressList.get(0);
    latitude = location.getLatitude();
     longitude = location.getLongitude();
     }