mylab

em kotlin: gps segunda versão

Adicionar uma dependência via menus no build-gradle (module)
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ficheiro: build-gradle(module)

...
dependencies {

    implementation "org.jetbrains.kotlin:kotlin-stdlib:$kotlin_version"
    implementation 'androidx.core:core-ktx:1.3.2'
    implementation 'androidx.appcompat:appcompat:1.2.0'
    implementation 'com.google.android.material:material:1.2.1'
    implementation 'androidx.constraintlayout:constraintlayout:2.0.4'
    implementation 'com.google.android.gms:play-services-location:17.1.0'
    testImplementation 'junit:junit:4.+'
    androidTestImplementation 'androidx.test.ext:junit:1.1.2'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.3.0'
}

ficheiro: AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="pt.isec.estuda.amov_gpsv1">

    <!-- pedir estas permissões -->
    <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/Theme.Amov_gpsv1">
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

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

</manifest>

ficheiro: MainActivity.kt

package pt.isec.estuda.amov_gpsv1

import android.Manifest
import android.content.pm.PackageManager
import android.location.Location
import android.location.LocationListener
import android.location.LocationManager
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.util.Log
import androidx.core.app.ActivityCompat
import com.google.android.gms.location.*

const val TAG = "Location"

class MainActivity : AppCompatActivity() {


    var locEnable = false //caso não ajam permissões

    lateinit var fLoc : FusedLocationProviderClient

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        fLoc = FusedLocationProviderClient(this)
    }

    override fun onResume() {
        super.onResume()
        startLocationServices(true)
        //para poupanças de energia, ativar o mais tarde possivel
    }

    override fun onPause() {
        super.onPause()
        //para poupanças de energia, desactivar o mais cedo possivel
        if(locEnable) {
            locEnable = false
        }
    }

    override fun onRequestPermissionsResult(requestCode: Int, permissions: Array<out String>, grantResults: IntArray) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults)
        //se tivermos as permissões
        //locationM.requestLocationUpdates(LocationManager.GPS_PROVIDER, 5000, 100f, this)
        if(requestCode == 1289) {
            startLocationServices(false)
        }
    }

    fun startLocationServices(askPerm : Boolean) {
        //1ºprovider, 2º intervalo de segundos,3º distancia minima ,4º  o listener
        //se for for telemovel NETWORK_PROVIDER
        //dar permissões: ACCESS_FINE_LOCATION
        //e pedir em runtime, add permissions check
        if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION)
                != PackageManager.PERMISSION_GRANTED
                && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION)
                != PackageManager.PERMISSION_GRANTED) {
            //pedir as permissões //&& ou ||
            if (askPerm) {
                ActivityCompat.requestPermissions(this, arrayOf(
                        Manifest.permission.ACCESS_FINE_LOCATION,
                        Manifest.permission.ACCESS_COARSE_LOCATION), 1289) //1289 um valor qualquer!
            } else {
                finish()
            }
            return
        }
        val locRequest = LocationRequest().apply {
            interval = 4000
            priority = LocationRequest.PRIORITY_HIGH_ACCURACY
            //ocultar para ja estes dois:
            //fastestInterval = 2000
            //maxWaitTime = 10000
            //numUpdates /? a ver, quantidade de updates
        }
        //activar
        locEnable = true
        fLoc.requestLocationUpdates(locRequest, locationCallBack, null)
    }


    }
    //função locationCallBack
    var locationCallBack = object : LocationCallback() {
        override fun onLocationResult(p0: LocationResult?) {
            Log.i(TAG, "onLocationAvailability: ")
            //locations é uma lista de localizações
            p0?.locations?.forEach {
                Log.i(TAG, "onLocationAvailability: ${it.latitude} ${it.longitude}")
            }
        }
}

Com esta versão são feitos updates mais rapidamente, com a ajuda do LocationRequest.PRIORITY_HIGH_ACCURACY
este é o método recomendado pela google..