准备
开发环境:
Android Studio 4.1.1
Build #AI-201.8743.12.41.6953283, built on November 5, 2020
Runtime version: 1.8.0_242-release-1644-b01 amd64
VM: OpenJDK 64-Bit Server VM by JetBrains s.r.o
Windows 10 10.0
GC: ParNew, ConcurrentMarkSweep
Memory: 1237M
Cores: 8
Registry: ide.new.welcome.screen.force=true, external.system.auto.import.disabled=true
项目
新建项目,选择 Empty Activity,在配置项目时,我选择的 Minimum SDK
是 API 16: Android 4.1 (Jelly Bean)
app\build.gradle
文件(这是默认的,我没有修改):
plugins {
id 'com.android.application'
}
android {
compileSdkVersion 30
buildToolsVersion "30.0.3"
defaultConfig {
applicationId "com.example.gotoenablelocationservice"
minSdkVersion 16
targetSdkVersion 30
versionCode 1
versionName "1.0"
testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
}
}
compileOptions {
sourceCompatibility JavaVersion.VERSION_1_8
targetCompatibility JavaVersion.VERSION_1_8
}
}
dependencies {
implementation 'androidx.appcompat:appcompat:1.1.0'
implementation 'com.google.android.material:material:1.1.0'
implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
testImplementation 'junit:junit:4.+'
androidTestImplementation 'androidx.test.ext:junit:1.1.1'
androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0'
}
编辑 src\main\res\layout\activity_main.xml
文件,删除原有的 TextView
元素,新增 Button
元素:
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.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">
<Button
android:id="@+id/button"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginStart="16dp"
android:layout_marginLeft="16dp"
android:layout_marginTop="16dp"
android:layout_marginEnd="16dp"
android:layout_marginRight="16dp"
android:text="Go To Enable Location Service"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
编辑 MainActivity
文件(主要代码是第 51、57 行):
package com.example.gotoenablelocationservice;
import androidx.annotation.Nullable;
import androidx.appcompat.app.AppCompatActivity;
import android.content.Context;
import android.content.Intent;
import android.location.LocationManager;
import android.os.Bundle;
import android.provider.Settings;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;
public class MainActivity extends AppCompatActivity {
private static final int REQUEST_CODE_GPS = 1;
private Button button = null;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initView();
}
@Override
protected void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == REQUEST_CODE_GPS) {
LocationManager locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
if (locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER)) {
Toast.makeText(MainActivity.this, "用户打开定位服务", Toast.LENGTH_LONG).show();
} else {
Toast.makeText(MainActivity.this, "用户关闭定位服务", Toast.LENGTH_LONG).show();
}
}
}
private void initView() {
button = (Button) findViewById(R.id.button);
button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
// https://developer.android.google.cn/guide/components/intents-filters?hl=zh-cn#ExampleSend
// https://developer.android.google.cn/reference/android/content/Intent?hl=zh-cn#resolveActivity(android.content.pm.PackageManager)
// 判断是否有合适的应用能够处理该 Intent,并且可以安全调用 startActivity()。
if (intent.resolveActivity(getPackageManager()) != null) {
startActivityForResult(intent, REQUEST_CODE_GPS);
} else {
Toast.makeText(MainActivity.this, "该设备不支持位置服务", Toast.LENGTH_SHORT).show();
}
}
});
}
}