Android GPS 位置找不到问题。如何更正此代码

Question

我是 android 的新手，所以如果这个非常基本的错误请原谅我，但我已经尝试了 3 天但找不到解决方案。

我只是想通过 gps 获取用户位置。

MainActivity.java

import android.Manifest;
import android.content.pm.PackageManager;
import android.location.Location;
import android.os.Looper;
import android.support.annotation.NonNull;
import android.support.v4.app.ActivityCompat;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;
import com.google.android.gms.location.FusedLocationProviderClient;
import com.google.android.gms.location.LocationCallback;
import com.google.android.gms.location.LocationRequest;
import com.google.android.gms.location.LocationResult;
import com.google.android.gms.location.LocationServices;
import com.google.android.gms.tasks.OnSuccessListener;


public class MainActivity extends AppCompatActivity {

//Variables

TextView lat, lng;
Button start, stop;

//Location
private FusedLocationProviderClient fusedLocationProviderClient;
private final static int FINE_LOCATION_REQUEST_CODE = 1000;
LocationRequest locationRequest;
LocationCallback locationCallback;


@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    //initializevar();

    fusedLocationProviderClient = LocationServices.getFusedLocationProviderClient(this);
    lat = (TextView)findViewById(R.id.lat);
    lng = (TextView)findViewById(R.id.lng);

    start = (Button)findViewById(R.id.begin);
    stop = (Button)findViewById(R.id.stop);


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

        ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.ACCESS_FINE_LOCATION}, FINE_LOCATION_REQUEST_CODE);
        Toast.makeText(this,"Reopen Apps",Toast.LENGTH_LONG);
    }
    else {

        buildlocationrequest();
        buildlocationcallback();

        //create fused provider client
        fusedLocationProviderClient = LocationServices. getFusedLocationProviderClient(this);

        stop.setEnabled(false);


        start.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {

                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) {
                    fusedLocationProviderClient.requestLocationUpdates(locationRequest, locationCallback, Looper.myLooper());
                    return;
                }



                String latt = "Fetching";
                String lngt = "Data";

                lat.setText(latt);
                lng.setText(lngt);

                fusedLocationProviderClient.requestLocationUpdates(locationRequest, locationCallback, Looper.myLooper());

                start.setEnabled(!start.isEnabled());
                stop.setEnabled(!stop.isEnabled());


            }
        });

        stop.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {

                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(MainActivity.this, new String[]{Manifest.permission.ACCESS_FINE_LOCATION}, FINE_LOCATION_REQUEST_CODE);
                    return;
                }
                fusedLocationProviderClient.removeLocationUpdates(locationCallback);

                start.setEnabled(!start.isEnabled());
                stop.setEnabled(!stop.isEnabled());
            }
        });
    }

}

private void buildlocationcallback() {
    locationCallback = new LocationCallback() {
        @Override
        public void onLocationResult(LocationResult locationResult) {
                for(Location location:locationResult.getLocations())
                {
                    //location mil gaya

                    String latt = "Latitude" + location.getLatitude();
                    String lngt = "Longitude" + location.getLongitude();

                    lat.setText(latt);
                    lng.setText(lngt);

                }
        }
    };
}

private void buildlocationrequest() {

    locationRequest = new LocationRequest();
    locationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
    locationRequest.setInterval(5000);
    locationRequest.setFastestInterval(3000);
    locationRequest.setSmallestDisplacement(10);
}

@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
    super.onRequestPermissionsResult(requestCode, permissions, grantResults);
    switch (requestCode)
    {
        case FINE_LOCATION_REQUEST_CODE :
            if(grantResults.length>0)
            {
                if(grantResults[0]==PackageManager.PERMISSION_GRANTED)
                {
                    Toast.makeText(this,"Permission Granted",Toast.LENGTH_LONG).show();
                }
                else if(grantResults[0]==PackageManager.PERMISSION_DENIED)
                {
                    Toast.makeText(this,"Permission Denied You need to enable first",Toast.LENGTH_LONG).show();
                }
            }
    }
}
}

build.gradle

    apply plugin: 'com.android.application'

android {
    compileSdkVersion 27
    defaultConfig {
        applicationId "com.my.gpstracker_myown"
        minSdkVersion 15
        targetSdkVersion 27
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation 'com.android.support:appcompat-v7:27.1.1'
    implementation 'com.android.support.constraint:constraint-layout:1.1.3'
    implementation'com.google.android.gms:play-services-location:16.0.0'
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'com.android.support.test:runner:1.0.2'
    androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'
}

AndroidManifest.xml

<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
<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/AppTheme">
    <activity android:name=".MainActivity">
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

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

我正在真实设备而不是模拟器上进行测试，没有获得任何位置更新，但出现在顶部位置图标（我的意思是应用正在请求位置的标志）。

提前致谢

Answer 1

在start.setOnClickListener(new View.OnClickListener()你正在检查

(ActivityCompat.checkSelfPermission(MainActivity.this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(MainActivity.this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) { fusedLocationProviderClient.requestLocationUpdates(locationRequest, locationCallback, Looper.myLooper()); return;

您需要将两个 != 替换为 ==

Android GPS 位置找不到问题。如何更正此代码

Android GPS location not finding issue. How to correct this code

java

android

runtime-error

android-gps