我有一些使用LocationManager通过GPS查找位置的代码。每当我尝试在手机(阿尔卡特OneTouch Fierce XL)上运行它时,我都会立即收到通知“不幸(我的应用程序名称)已停止”。只有在应用程序的智能手机上启用了位置服务后,此错误才会正常运行。
我尝试了可以使用的任何示例代码,但结果却相同。
这是我的代码:
初始化GPS:
locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
if (ActivityCompat.checkSelfPermission(this, permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
// TODO: Consider calling
// ActivityCompat#requestPermissions
// here to request the missing permissions, and then overriding
// public void onRequestPermissionsResult(int requestCode, String[] permissions,
// int[] grantResults)
// to handle the case where the user grants the permission. See the documentation
// for ActivityCompat#requestPermissions for more details.
return;
}
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, (LocationListener) this);
我使用的方法:
//Location stuff
public void onLocationChanged(Location location) {
Toast.makeText(this, "Latitude:" + location.getLatitude() + ", Longitude:" + location.getLongitude(), Toast.LENGTH_LONG);
try {
wait(5000);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
public void onProviderDisabled(String provider) {
Log.d("Latitude","disable");
}
public void onProviderEnabled(String provider) {
Log.d("Latitude","enable");
}
public void onStatusChanged(String provider, int status, Bundle extras) {
Log.d("Latitude","status");
}
堆栈跟踪:
E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.eas, PID: 11330
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.eas/com.example.eas.MainActivity}: java.lang.ClassCastException: com.example.eas.MainActivity cannot be cast to android.location.LocationListener
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2365)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2427)
at android.app.ActivityThread.access$800(ActivityThread.java:156)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1331)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5333)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:940)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:735)
Caused by: java.lang.ClassCastException: com.example.eas.MainActivity cannot be cast to android.location.LocationListener
at com.example.eas.MainActivity.onCreate(MainActivity.java:50)
at android.app.Activity.performCreate(Activity.java:6036)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1109)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2318)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2427)
at android.app.ActivityThread.access$800(ActivityThread.java:156)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1331)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5333)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:940)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:735)
答案 0 :(得分:2)
您的例外是:
Caused by: java.lang.ClassCastException: com.example.eas.MainActivity cannot be cast to android.location.LocationListener
它似乎来自:
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, (LocationListener) this);
this
(这似乎是您的活动)未实现LocationListener
接口。添加该接口,并确保已实现该接口所需的所有方法。
您可以在Oracle's documentation中了解有关Java接口的更多信息。