我是这个社区的新成员，但我已经从你们那里学到了很多东西！实际上，我开始使用Android Studio编程，但现在我卡在某个地方了。我相信这是一些简单的问题，你会很快发现。
在模拟器Nexus 5 API 23（已经安装在Android Studio中）上可以运行，但在我的手机Android 5.1.1 API 22上无法启动。
错误：
09-20 19:15:11.526 17776-17776/com.example.stefano.aiutomamma01 E/AndroidRuntime﹕ FATAL EXCEPTION: main
Process: com.example.stefano.aiutomamma01, PID: 17776
java.lang.NoSuchMethodError: No virtual method checkSelfPermission(Ljava/lang/String;)I in class Lcom/example/stefano/aiutomamma01/MainActivity; or its super classes (declaration of 'com.example.stefano.aiutomamma01.MainActivity' appears in /data/app/com.example.stefano.aiutomamma01-2/base.apk)
at com.example.stefano.aiutomamma01.MainActivity.onCreate(MainActivity.java:28)
at android.app.Activity.performCreate(Activity.java:5990)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1106)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2332)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2442)
at android.app.ActivityThread.access$800(ActivityThread.java:156)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1351)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:211)
at android.app.ActivityThread.main(ActivityThread.java:5373)
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:1020)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:815)
JAVA代码：
package com.example.stefano.aiutomamma01;
import android.Manifest;
import android.content.Context;
import android.content.pm.PackageManager;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.Toast;
public class MainActivity extends AppCompatActivity implements LocationListener {
//GPS
private LocationManager locationManager;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//GPS
locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
//CATCHED
if (checkSelfPermission(Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && checkSelfPermission(Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
// TODO: Consider calling
// public void requestPermissions(@NonNull String[] permissions, int requestCode)
// 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 Activity#requestPermissions for more details.
return;
}
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, this);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
//GPS
@Override
public void onLocationChanged(Location location) {
String str = "Latitude: " + location.getLatitude() + "Longitude: " + location.getLongitude();
Toast.makeText(getBaseContext(), str, Toast.LENGTH_LONG).show();
}
//GPS
@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
//GPS
@Override
public void onProviderEnabled(String provider) {
}
//GPS
@Override
public void onProviderDisabled(String provider) {
}
}
很抱歉这篇文章写得不好。顺便说一下：我在网上找不到解决方案...
问候
ActivityCompat类方法以向后兼容的方式处理它们。 - Eugen Pechanec