java - 谷歌地图无法加载 map

Question

为什么我无法在 Android Studio 中使用 google map 。单击按钮离开 MainActivity 后，它尝试从 MapActivity 运行代码，但 map 永远不会弹出。它只显示一个空白背景，左下角有谷歌 Logo 。我将发布必要的文件和模拟器的图片。

build.gradle(项目:GPS2)

buildscript {

    repositories {
        google()
        jcenter()
        maven {
            url "https://maven.google.com"
        }
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.1.3'


        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}

allprojects {
    repositories {
        google()
        jcenter()
        maven {
            url "https://maven.google.com"
        }

    }
}

task clean(type: Delete) {
    delete rootProject.buildDir
}

//build.gradle (Module: app)

apply plugin: 'com.android.application'

android {
    compileSdkVersion 28
    defaultConfig {
        applicationId "com.gps2.scooberapp"
        minSdkVersion 17
        targetSdkVersion 28
        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(include: ['*.jar'], dir: 'libs')
    implementation 'com.android.support:appcompat-v7:28.0.0-alpha3'
    implementation 'com.android.support.constraint:constraint-layout:1.1.2'
    implementation 'com.google.android.gms:play-services-maps:15.0.1'
    implementation 'com.google.android.gms:play-services-places:15.0.1'

    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

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.gps2.scooberapp">

    <permission android:name="com.gps2.scooberapp.permission.MAPS_RECEIVE" android:protectionLevel="signature"/>
    <uses-permission android:name="com.example.permission.MAPS_RECEIVE"/>
    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
    <uses-permission android:name="android.permission.INTERNET"/>
    <uses-permission android:name="com.google.android.providers.gsf.permission.READ_GSERVICES"/>
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
    <uses-feature android:glEsVersion="0x00020000" android:required="true"/>

    <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>
        <activity android:name=".MapActivity"/>
        <meta-data
            android:name="com.google.android.geo.API_KEY"
            android:value="@string/google_maps_key"/>
        <meta-data
            android:name="com.google.android.gms.version"
            android:value="@integer/google_play_services_version" />
    </application>
</manifest>

activity_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="com.gps2.scooberapp.MainActivity">

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Map"
        android:id="@+id/btnMap"/>

</android.support.constraint.ConstraintLayout>

activity_map.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <fragment xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:tools="http://schemas.android.com/tools"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:id="@+id/map"
        tools:context=".MapActivity"
        android:name="com.google.android.gms.maps.SupportMapFragment" />

</RelativeLayout>

MainActivity.java

package com.gps2.scooberapp;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.app.Dialog;
import android.content.Intent;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;

import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.GoogleApiAvailability;

public class MainActivity extends AppCompatActivity {

    private static final String TAG = "MainActivity";

    private static final int ERROR_DIALOG_REQUEST = 9001;


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

        if(isServicesOK()){
            init();
        }
    }

    private void init(){
        Button btnMap = (Button) findViewById(R.id.btnMap);
        btnMap.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Intent intent = new Intent(MainActivity.this, MapActivity.class);
                startActivity(intent);
            }
        });
    }

    public boolean isServicesOK(){
        Log.d(TAG, "isServicesOK: checking google services version");

        int available = GoogleApiAvailability.getInstance().isGooglePlayServicesAvailable(MainActivity.this);

        if(available == ConnectionResult.SUCCESS){
            //everything is fine and the user can make map requests
            Log.d(TAG, "isServicesOK: Google Play Services is working");
            return true;
        }
        else if(GoogleApiAvailability.getInstance().isUserResolvableError(available)){
            //an error occured but we can resolve it
            Log.d(TAG, "isServicesOK: an error occured but we can fix it");
            Dialog dialog = GoogleApiAvailability.getInstance().getErrorDialog(MainActivity.this, available, ERROR_DIALOG_REQUEST);
            dialog.show();
        }else{
            Toast.makeText(this, "You can't make map requests", Toast.LENGTH_SHORT).show();
        }
        return false;
    }

}

MapActivity.java

package com.gps2.scooberapp;

import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v7.app.AppCompatActivity;

import android.*;
import android.Manifest;
import android.content.pm.PackageManager;
import android.support.annotation.NonNull;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.util.Log;
import android.widget.Toast;

import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.OnMapReadyCallback;
import com.google.android.gms.maps.SupportMapFragment;


public class MapActivity extends AppCompatActivity implements OnMapReadyCallback{

    @Override
    public void onMapReady(GoogleMap googleMap) {
        Toast.makeText(this, "Map is Ready", Toast.LENGTH_SHORT).show();
        Log.d(TAG, "onMapReady: map is ready");
        mMap = googleMap;
    }

    private static final String TAG = "MapActivity";

    private static final String FINE_LOCATION = Manifest.permission.ACCESS_FINE_LOCATION;
    private static final String COURSE_LOCATION = Manifest.permission.ACCESS_COARSE_LOCATION;
    private static final int LOCATION_PERMISSION_REQUEST_CODE = 1234;

    //vars
    private Boolean mLocationPermissionsGranted = false;
    private GoogleMap mMap;

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

        getLocationPermission();
    }

    private void initMap(){
        Log.d(TAG, "initMap: initializing map");
        SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map);

        mapFragment.getMapAsync(MapActivity.this);
    }

    private void getLocationPermission(){
        Log.d(TAG, "getLocationPermission: getting location permissions");
        String[] permissions = {Manifest.permission.ACCESS_FINE_LOCATION,
                Manifest.permission.ACCESS_COARSE_LOCATION};

        if(ContextCompat.checkSelfPermission(this.getApplicationContext(),
                FINE_LOCATION) == PackageManager.PERMISSION_GRANTED){
            if(ContextCompat.checkSelfPermission(this.getApplicationContext(),
                    COURSE_LOCATION) == PackageManager.PERMISSION_GRANTED){
                mLocationPermissionsGranted = true;
            }else{
                ActivityCompat.requestPermissions(this,
                        permissions,
                        LOCATION_PERMISSION_REQUEST_CODE);
            }
        }else{
            ActivityCompat.requestPermissions(this,
                    permissions,
                    LOCATION_PERMISSION_REQUEST_CODE);
        }
    }

    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        Log.d(TAG, "onRequestPermissionsResult: called.");
        mLocationPermissionsGranted = false;

        switch(requestCode){
            case LOCATION_PERMISSION_REQUEST_CODE:{
                if(grantResults.length > 0){
                    for(int i = 0; i < grantResults.length; i++){
                        if(grantResults[i] != PackageManager.PERMISSION_GRANTED){
                            mLocationPermissionsGranted = false;
                            Log.d(TAG, "onRequestPermissionsResult: permission failed");
                            return;
                        }
                    }
                    Log.d(TAG, "onRequestPermissionsResult: permission granted");
                    mLocationPermissionsGranted = true;
                    //initialize our map
                    initMap();
                }
            }
        }
    }
}

Answer 1

1. 您需要使用您的 Google 开发者帐户 here 登录.

2. 如果尚未完成，请为您的应用创建一个项目。

3. 启用 _Maps SDK for Android(Maps SDK for iOS，如果需要的话)。

4. 您将在凭据菜单中收到一个 API key 。

5. 将您的 API key 复制/粘贴到调试文件夹和发布文件夹中的 google_maps_api.xml 文件中。

6. 将您的应用添加到 Google Developers Console 中:您将需要 SHA-1 fingerprint of your app .

完成这些步骤后，您就可以使用 Google Maps Api ;)