如何使用 GPS 在 Android 中获取我的当前位置？

我想通过 GPS 以地址形式获取我当前的位置。我正在使用android studio。 它说我的应用程序停止工作。 其中有什么错误呢？ 有人可以帮我摆脱这个困境吗？

我在 Activity_main.xml 文件中的代码是

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout 
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">

<TextView
    android:id="@+id/text_view"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Hello World!"
    app:layout_constraintBottom_toBottomOf="parent"
    app:layout_constraintLeft_toLeftOf="parent"
    app:layout_constraintRight_toRightOf="parent"
    app:layout_constraintTop_toTopOf="parent" />

我在 MainActivity.java 中的代码是

package com.example.showlatlong;

import androidx.appcompat.app.AppCompatActivity;
import androidx.core.app.ActivityCompat;

import android.Manifest;
import android.content.Context;
import android.content.pm.PackageManager;
import android.location.Address;
import android.location.Geocoder;
import android.location.Location;
import android.location.LocationManager;
import android.os.Bundle;
import android.widget.TextView;

import java.util.List;
import java.util.Locale;

public class MainActivity extends AppCompatActivity {

Location gps_loc, network_loc, final_loc;
double longitude;
double latitude;
String userCountry, userAddress;


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

    TextView tv = findViewById(R.id.text_view);

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


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

        return;
    }

    try {
        gps_loc = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
        network_loc = locationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
    } catch (Exception e) {
        e.printStackTrace();
    }

    if (gps_loc != null) {
        final_loc = gps_loc;
        latitude = final_loc.getLatitude();
        longitude = final_loc.getLongitude();
    }
    else if (network_loc != null) {
        final_loc = network_loc;
        latitude = final_loc.getLatitude();
        longitude = final_loc.getLongitude();
    }
    else {
        latitude = 0.0;
        longitude = 0.0;
    }

     ActivityCompat.requestPermissions(this, new String[] {Manifest.permission.ACCESS_FINE_LOCATION, Manifest.permission.ACCESS_COARSE_LOCATION, Manifest.permission.ACCESS_NETWORK_STATE}, 1);



    try {

        Geocoder geocoder = new Geocoder(this, Locale.getDefault());
        List<Address> addresses = geocoder.getFromLocation(latitude, longitude, 1);
        if (addresses != null && addresses.size() > 0) {
            userCountry = addresses.get(0).getCountryName();
            userAddress = addresses.get(0).getAddressLine(0);
            tv.setText(userCountry + ", " + userAddress);
        }
        else {
            userCountry = "Unknown";
            tv.setText(userCountry);
        }

    } catch (Exception e) {
        e.printStackTrace();
    }

}

}

我在manifest.xml中的代码是

<?xml version="1.0" encoding="utf-8"?>

<uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>

<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>

整个代码是这样的。它正在打开应用程序，不到一秒钟，它就会通过在我的 Android 应用程序上抛出“应用程序不断停止”的错误消息来关闭。 这是我在 logcat 中得到的

2019-09-11 12:58:45.344 15400-15400/com.example.showlatlong E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.showlatlong, PID: 15400
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.showlatlong/com.example.showlatlong.MainActivity}: android.view.InflateException: Binary XML file line #2: Binary XML file line #2: Error inflating class android.support.constraint.ConstraintLayout
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2723)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2784)
    at android.app.ActivityThread.-wrap12(ActivityThread.java)
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1523)
    at android.os.Handler.dispatchMessage(Handler.java:102)
    at android.os.Looper.loop(Looper.java:163)
    at android.app.ActivityThread.main(ActivityThread.java:6238)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:933)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:823)
 Caused by: android.view.InflateException: Binary XML file line #2: Binary XML file line #2: Error inflating class android.support.constraint.ConstraintLayout
 Caused by: android.view.InflateException: Binary XML file line #2: Error inflating class android.support.constraint.ConstraintLayout
 Caused by: java.lang.ClassNotFoundException: Didn't find class "android.support.constraint.ConstraintLayout" on path: DexPathList[[zip file "/data/app/com.example.showlatlong-1/base.apk", zip file "/data/app/com.example.showlatlong-1/split_lib_dependencies_apk.apk", zip file "/data/app/com.example.showlatlong-1/split_lib_slice_0_apk.apk", zip file "/data/app/com.example.showlatlong-1/split_lib_slice_1_apk.apk", zip file "/data/app/com.example.showlatlong-1/split_lib_slice_2_apk.apk", zip file "/data/app/com.example.showlatlong-1/split_lib_slice_3_apk.apk", zip file "/data/app/com.example.showlatlong-1/split_lib_slice_4_apk.apk", zip file "/data/app/com.example.showlatlong-1/split_lib_slice_5_apk.apk", zip file "/data/app/com.example.showlatlong-1/split_lib_slice_6_apk.apk", zip file "/data/app/com.example.showlatlong-1/split_lib_slice_7_apk.apk", zip file "/data/app/com.example.showlatlong-1/split_lib_slice_8_apk.apk", zip file "/data/app/com.example.showlatlong-1/split_lib_slice_9_apk.apk"],nativeLibraryDirectories=[/data/app/com.example.showlatlong-1/lib/arm64, /system/lib64, /vendor/lib64]]
    at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:56)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:380)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:312)
    at android.view.LayoutInflater.createView(LayoutInflater.java:613)
    at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:812)
    at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:752)
    at android.view.LayoutInflater.inflate(LayoutInflater.java:499)
    at android.view.LayoutInflater.inflate(LayoutInflater.java:430)
    at android.view.LayoutInflater.inflate(LayoutInflater.java:377)
    at androidx.appcompat.app.AppCompatDelegateImpl.setContentView(AppCompatDelegateImpl.java:555)
    at androidx.appcompat.app.AppCompatActivity.setContentView(AppCompatActivity.java:161)
    at com.example.showlatlong.MainActivity.onCreate(MainActivity.java:29)
    at android.app.Activity.performCreate(Activity.java:6857)
    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1119)
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2676)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2784)
    at android.app.ActivityThread.-wrap12(ActivityThread.java)
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1523)
    at android.os.Handler.dispatchMessage(Handler.java:102)
    at android.os.Looper.loop(Looper.java:163)
    at android.app.ActivityThread.main(ActivityThread.java:6238)
    at java.lang.reflect.Method.invoke(Native Method)
    at 


 com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit. 
 java:933)
 2019-09-11 12:58:45.344 15400-15400/com.example.showlatlong  
 E/AndroidRuntime:     
 at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:823)

在 AndroidManifest.xml 中，您必须将其放在应用程序标记的上方或下方。

<uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>

因为你没有显示你的代码你一直在做什么，所以我不知道如何解决你的问题。但下面的代码是我在应用程序中用于获取当前用户所在国家/地区的代码。

活动_main.xml

    <?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <TextView
        android:id="@+id/text_view"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hello World!"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

</android.support.constraint.ConstraintLayout>

MainActivity.java

import android.Manifest;
import android.content.Context;
import android.content.pm.PackageManager;
import android.location.Address;
import android.location.Geocoder;
import android.location.Location;
import android.location.LocationManager;
import android.support.v4.app.ActivityCompat;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.TextView;

import java.util.List;
import java.util.Locale;

public class MainActivity extends AppCompatActivity {

        Location gps_loc;
        Location network_loc;
        Location final_loc;
        double longitude;
        double latitude;
        String userCountry, userAddress;

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


        TextView tv = findViewById(R.id.text_view);

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


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

            return;
        }

        try {

            gps_loc = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
            network_loc = locationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);

        } catch (Exception e) {
            e.printStackTrace();
        }

        if (gps_loc != null) {
            final_loc = gps_loc;
            latitude = final_loc.getLatitude();
            longitude = final_loc.getLongitude();
        }
        else if (network_loc != null) {
            final_loc = network_loc;
            latitude = final_loc.getLatitude();
            longitude = final_loc.getLongitude();
        }
        else {
            latitude = 0.0;
            longitude = 0.0;
        }


        ActivityCompat.requestPermissions(this, new String[] {Manifest.permission.ACCESS_FINE_LOCATION, Manifest.permission.ACCESS_COARSE_LOCATION, Manifest.permission.ACCESS_NETWORK_STATE}, 1);

        try {

            Geocoder geocoder = new Geocoder(this, Locale.getDefault());
            List<Address> addresses = geocoder.getFromLocation(latitude, longitude, 1);
            if (addresses != null && addresses.size() > 0) {
                userCountry = addresses.get(0).getCountryName();
                userAddress = addresses.get(0).getAddressLine(0);
                tv.setText(userCountry + ", " + userAddress);
            }
            else {
                userCountry = "Unknown";
                tv.setText(userCountry);
            }

        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

你不得不理解这段代码。另一件事是，如果您在模拟器上运行应用程序，它将继续显示“美国”或更具体地说，Googleplex 的位置。只需在真实设备上运行它即可返回您当前的位置。

要返回您当前的位置而不仅仅是国家/地区本身，您可以替换

地址.get(0).getCountryName()

与类似的东西

地址.get(0).getPostalCode()

or

地址.get(0).getAdminArea()

等等。

您也可以将这些值连接为字符串以详细显示您当前的位置。

请看一下this