java - 无法从 LocationManager (Android Studio) 获取纬度和经度

Question

我正在尝试使用位置管理器来获取我当前位置的纬度和经度。但是每当我按下“开始”时，它就会返回我cannot find location。有谁知道是什么导致了这个问题？虽然 GPS 可能无法在虚拟设备上运行，但我用我的实际设备（Pocophone f1）测试了该程序，这可能不是问题所在。除此之外，我切换到移动数据它可以工作一秒钟，但不会持续很长时间。

错误：

显现

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.sossystem">

    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
    <uses-permission android:name="android.permission.FOREGROUND_SERVICE"/>
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/Theme.SOSsystem">
        <activity android:name=".Admin_hospital"></activity>
        <activity
            android:name=".Admin_bomba"
            android:label="@string/title_activity_admin_bomba"
            android:theme="@style/Theme.SOSsystem.NoActionBar" />
        <activity android:name=".Admin_police" />
        <activity android:name=".Login">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <activity android:name=".Register" />
        <activity android:name=".MainActivity" />
    </application>

</manifest>

Java代码：

public class MainActivity extends AppCompatActivity {

    private static  final int REQUEST_LOCATION=1;

    Button getlocationBtn;
    TextView showLocationTxt;

    LocationManager locationManager;
    String latitude,longitude;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Button logout = findViewById(R.id.logoutBtn);

        //Add permission

        ActivityCompat.requestPermissions(this,new String[]
                {Manifest.permission.ACCESS_FINE_LOCATION}, REQUEST_LOCATION);

        showLocationTxt=findViewById(R.id.show_location);
        getlocationBtn=findViewById(R.id.getLocation);




        logout.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                FirebaseAuth.getInstance().signOut();
                startActivity(new Intent(getApplicationContext(), Login.class));
                finish();
            }
        });


        getlocationBtn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                locationManager=(LocationManager) getSystemService(Context.LOCATION_SERVICE);

                //Check gps is enable or not

                if (!locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER))
                {
                    //Write Function To enable gps

                    OnGPS();
                }
                else
                {
                    //GPS is already On then

                    getLocation();
                }
            }
        });

    }

    private void getLocation() {

        //Check Permissions again

        if (ActivityCompat.checkSelfPermission(MainActivity.this,Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(MainActivity.this,

                Manifest.permission.ACCESS_COARSE_LOCATION) !=PackageManager.PERMISSION_GRANTED)
        {
            ActivityCompat.requestPermissions(this,new String[]
                    {Manifest.permission.ACCESS_FINE_LOCATION}, REQUEST_LOCATION);
        }
        else
        {
            Location LocationGps= locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
            Location LocationNetwork=locationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
            Location LocationPassive=locationManager.getLastKnownLocation(LocationManager.PASSIVE_PROVIDER);

            if (LocationGps !=null)
            {
                double lat=LocationGps.getLatitude();
                double longi=LocationGps.getLongitude();

                latitude=String.valueOf(lat);
                longitude=String.valueOf(longi);

                showLocationTxt.setText("Your Location:"+"\n"+"Latitude= "+latitude+"\n"+"Longitude= "+longitude);
            }
            else if (LocationNetwork !=null)
            {
                double lat=LocationNetwork.getLatitude();
                double longi=LocationNetwork.getLongitude();

                latitude=String.valueOf(lat);
                longitude=String.valueOf(longi);

                showLocationTxt.setText("Your Location:"+"\n"+"Latitude= "+latitude+"\n"+"Longitude= "+longitude);
            }
            else if (LocationPassive !=null)
            {
                double lat=LocationPassive.getLatitude();
                double longi=LocationPassive.getLongitude();

                latitude=String.valueOf(lat);
                longitude=String.valueOf(longi);

                showLocationTxt.setText("Your Location:"+"\n"+"Latitude= "+latitude+"\n"+"Longitude= "+longitude);
            }
            else
            {
                Toast.makeText(this, "Can't Get Your Location", Toast.LENGTH_SHORT).show();
            }

            //Thats All Run Your App
        }

    }

    private void OnGPS() {

        final AlertDialog.Builder builder= new AlertDialog.Builder(this);

        builder.setMessage("Enable GPS").setCancelable(false).setPositiveButton("YES", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                startActivity(new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS));
            }
        }).setNegativeButton("NO", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {

                dialog.cancel();
            }
        });
        final AlertDialog alertDialog=builder.create();
        alertDialog.show();
    }

    }

标签： javaandroidandroid-studiogpslocationmanager