[Android] Google Map 地図を表示させる

Google Mapアプリを作る場合には、プロジェクトの新規作成でMAPアプリを選択すると簡単に出来上がります。

Android Studio
2021.2.1

Google Map アプリ

マップアプリは、簡単にIntentでアプリに飛ばしてしまうこともできます
Intentでの簡単なGoogle Map 地図の表示

プロジェクトで Mapアプリ選択しても簡単にできます。

ここでは、デフォルトの地図を表示させた後に
特定の緯度、経度を指定して地図を拡大ズームさせるところまで試してみます。　

目次
1. Google Map プロジェクトの作成
2. Map アプリコード
3. 緯度、経度、ズーム

Google Map プロジェクトの作成

プロジェクトを新規で作成するときにMAPアプリを選ぶと簡単にセットアップされます
Google Maps Activity を選択
　

Projectが作成されると AndroidManifest.xml が現れてAPIキーを取得するための
URLが表示されます。

以前はリンクが ~~google_maps_api.xml~~ にありましたが、もうありません。

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    ...
        <!--
             TODO: Before you run your application, you need a Google Maps API key.

             To get one, follow the directions here:

                https://developers.google.com/maps/documentation/android-sdk/get-api-key

             Once you have your API key (it starts with "AIza"), define a new property in your
             project's local.properties file (e.g. MAPS_API_KEY=Aiza...), and replace the
             "YOUR_API_KEY" string in this file with "${MAPS_API_KEY}".
        -->

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

<manifest xmlns:android="http://schemas.android.com/apk/res/android"

...

<!--

TODO: Before you run your application, you need a Google Maps API key.

To get one, follow the directions here:

https://developers.google.com/maps/documentation/android-sdk/get-api-key

Once you have your API key (it starts with "AIza"), define a new property in your

project's local.properties file (e.g. MAPS_API_KEY=Aiza...), and replace the

"YOUR_API_KEY" string in this file with "${MAPS_API_KEY}".

-->

以下の手順に沿ってAPIキーを入手します
　

x13.4 gmap 00a 100x100 - [Android] Google Map 地図を表示させる

[Android] Google Maps API キーを取得

Android アプリでGoogle Mapを使うためには、GoogleからAPIキーを取得する必要があります APIキーを取得するや...

　
AndroidManifest.xml に説明がありましたが、取得したAPIキーを
local.propertiesに記述します

## This file is automatically generated by Android Studio.
...
sdk.dir=C\:\\Users\\akira\\AppData\\Local\\Android\\Sdk

MAPS_API_KEY=AIzaISyBC4N47_xxxxxxxxxxxxxxxxxxxHiRwU

## This file is automatically generated by Android Studio.

...

sdk.dir=C\:\\Users\\akira\\AppData\\Local\\Android\\Sdk

MAPS_API_KEY=AIzaISyBC4N47_xxxxxxxxxxxxxxxxxxxHiRwU

AndroidManifest.xml のYOUR_API_KEY を{MAPS_API_KEY}に置き換えます

<meta-data
            android:name="com.google.android.geo.API_KEY"
            android:value="${MAPS_API_KEY}" />

<meta-data

android:name="com.google.android.geo.API_KEY"

android:value="${MAPS_API_KEY}" />

これで設定が終わったので実行すると
シドニーにマークされた地図が表示されると思います。
　

Map アプリコード

コードが以下のようにできています。
Google Maps Activity で作成されたままです
　
MapsActivity.java

//package your.package.name;

import androidx.fragment.app.FragmentActivity;
import android.os.Bundle;
import com.google.android.gms.maps.CameraUpdateFactory;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.OnMapReadyCallback;
import com.google.android.gms.maps.SupportMapFragment;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.MarkerOptions;
import com.example.testgooglemap01.databinding.ActivityMapsBinding;

public class MapsActivity extends FragmentActivity implements OnMapReadyCallback {

    private GoogleMap mMap;
    private ActivityMapsBinding binding;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        binding = ActivityMapsBinding.inflate(getLayoutInflater());
        setContentView(binding.getRoot());

        // Obtain the SupportMapFragment and get notified when the map is ready to be used.
        SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager()
                .findFragmentById(R.id.map);
        mapFragment.getMapAsync(this);
    }

    /**
     * Manipulates the map once available.
     * This callback is triggered when the map is ready to be used.
     * This is where we can add markers or lines, add listeners or move the camera. In this case,
     * we just add a marker near Sydney, Australia.
     * If Google Play services is not installed on the device, the user will be prompted to install
     * it inside the SupportMapFragment. This method will only be triggered once the user has
     * installed Google Play services and returned to the app.
     */
    @Override
    public void onMapReady(GoogleMap googleMap) {
        mMap = googleMap;

        // Add a marker in Sydney and move the camera
        LatLng sydney = new LatLng(-34, 151);
        mMap.addMarker(new MarkerOptions().position(sydney).title("Marker in Sydney"));
        mMap.moveCamera(CameraUpdateFactory.newLatLng(sydney));
    }
}

//package your.package.name;

import androidx.fragment.app.FragmentActivity;

import android.os.Bundle;

import com.google.android.gms.maps.CameraUpdateFactory;

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

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

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

import com.google.android.gms.maps.model.LatLng;

import com.google.android.gms.maps.model.MarkerOptions;

import com.example.testgooglemap01.databinding.ActivityMapsBinding;

public class MapsActivity extends FragmentActivity implements OnMapReadyCallback {

private GoogleMap mMap;

private ActivityMapsBinding binding;

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

binding = ActivityMapsBinding.inflate(getLayoutInflater());

setContentView(binding.getRoot());

// Obtain the SupportMapFragment and get notified when the map is ready to be used.

SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager()

.findFragmentById(R.id.map);

mapFragment.getMapAsync(this);

}

/**

* Manipulates the map once available.

* This callback is triggered when the map is ready to be used.

* This is where we can add markers or lines, add listeners or move the camera. In this case,

* we just add a marker near Sydney, Australia.

* If Google Play services is not installed on the device, the user will be prompted to install

* it inside the SupportMapFragment. This method will only be triggered once the user has

* installed Google Play services and returned to the app.

@Override

public void onMapReady(GoogleMap googleMap) {

mMap = googleMap;

// Add a marker in Sydney and move the camera

LatLng sydney = new LatLng(-34, 151);

mMap.addMarker(new MarkerOptions().position(sydney).title("Marker in Sydney"));

mMap.moveCamera(CameraUpdateFactory.newLatLng(sydney));

}

　
activity_maps.xml

<?xml version="1.0" encoding="utf-8"?>
<fragment xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:map="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/map"
    android:name="com.google.android.gms.maps.SupportMapFragment"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MapsActivity" />

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

<fragment xmlns:android="http://schemas.android.com/apk/res/android"

xmlns:map="http://schemas.android.com/apk/res-auto"

xmlns:tools="http://schemas.android.com/tools"

android:id="@+id/map"

android:name="com.google.android.gms.maps.SupportMapFragment"

android:layout_width="match_parent"

android:layout_height="match_parent"

tools:context=".MapsActivity" />

ここはGoogle Map Keyを入れるだけです
AndroidManifest.xml

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

    <application
        ...
        tools:targetApi="31">

        <!--
             TODO: Before you run your application, you need a Google Maps API key.

             To get one, follow the directions here:

                https://developers.google.com/maps/documentation/android-sdk/get-api-key

             Once you have your API key (it starts with "AIza"), define a new property in your
             project's local.properties file (e.g. MAPS_API_KEY=Aiza...), and replace the
             "YOUR_API_KEY" string in this file with "${MAPS_API_KEY}".
        -->
        <meta-data
            android:name="com.google.android.geo.API_KEY"
            android:value="${MAPS_API_KEY}" />

        <activity
            ...
        </activity>
    </application>

</manifest>

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

<manifest xmlns:android="http://schemas.android.com/apk/res/android"

...

<application

...

tools:targetApi="31">

<!--

TODO: Before you run your application, you need a Google Maps API key.

To get one, follow the directions here:

https://developers.google.com/maps/documentation/android-sdk/get-api-key

Once you have your API key (it starts with "AIza"), define a new property in your

project's local.properties file (e.g. MAPS_API_KEY=Aiza...), and replace the

"YOUR_API_KEY" string in this file with "${MAPS_API_KEY}".

-->

<meta-data

android:name="com.google.android.geo.API_KEY"

android:value="${MAPS_API_KEY}" />

<activity

...

</activity>

</application>

</manifest>

　
APIキーが追加されています
local.properties

## This file is automatically generated by Android Studio.
...
sdk.dir=C\:\\Users\\akira\\AppData\\Local\\Android\\Sdk

MAPS_API_KEY=AIzaISyBC4N47_xxxxxxxxxxxxxxxxxxxHiRwU

## This file is automatically generated by Android Studio.

...

sdk.dir=C\:\\Users\\akira\\AppData\\Local\\Android\\Sdk

MAPS_API_KEY=AIzaISyBC4N47_xxxxxxxxxxxxxxxxxxxHiRwU

緯度、経度、ズーム

できているコードに変更を加えてみます。緯度経度とズームの指定は

CameraUpdate cUpdate = CameraUpdateFactory.newLatLngZoom( new LatLng(緯度, 経度), ズーム)

1	CameraUpdate cUpdate = CameraUpdateFactory.newLatLngZoom( new LatLng(緯度, 経度), ズーム)

を使ってできます
　
MapsActivityの中のonMapReadyで設定します

import com.google.android.gms.maps.CameraUpdate;
...
@Override
    public void onMapReady(GoogleMap googleMap) {
        mMap = googleMap;

        // Add a marker in Sydney and move the camera
        LatLng sydney = new LatLng(-34, 151);
        mMap.addMarker(new MarkerOptions().position(sydney).title("Marker in Sydney"));
        mMap.moveCamera(CameraUpdateFactory.newLatLng(sydney));

        CameraUpdate cUpdate = CameraUpdateFactory.newLatLngZoom( 
                                        new LatLng(35.68, 139.76), 12);
        mMap.moveCamera(cUpdate);

    }

import com.google.android.gms.maps.CameraUpdate;

...

@Override

public void onMapReady(GoogleMap googleMap) {

mMap = googleMap;

// Add a marker in Sydney and move the camera

LatLng sydney = new LatLng(-34, 151);

mMap.addMarker(new MarkerOptions().position(sydney).title("Marker in Sydney"));

mMap.moveCamera(CameraUpdateFactory.newLatLng(sydney));

CameraUpdate cUpdate = CameraUpdateFactory.newLatLngZoom(

new LatLng(35.68, 139.76), 12);

mMap.moveCamera(cUpdate);

}