FusedLocationApi.getLastLocation 总是返回 null(android 6.0,api 23)

Question

我在手机上试试。它总是返回 null。为什么？（授予所有权限。ACCESS_COARSE_LOCATION ACCESS_FINE_LOCATION)

fusedLocationClient = LocationServices.getFusedLocationProviderClient(this);
    if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION)
            != PackageManager.PERMISSION_GRANTED &&
            ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION)
                    != PackageManager.PERMISSION_GRANTED) {
        return;
    }
    fusedLocationClient.getLastLocation()
            .addOnSuccessListener(this, new OnSuccessListener<Location>() {
                @Override
                public void onSuccess(Location location) {
                    if (location != null) {
                        Toast.makeText(MainActivity.this, "Location: "+location, Toast.LENGTH_SHORT).show();
                    }
                    else{
                        Toast.makeText(MainActivity.this, "null", Toast.LENGTH_SHORT).show();
                    }

            });

依赖关系：

dependencies {
implementation fileTree(include: ['*.jar'], dir: 'libs')
implementation 'com.android.support:appcompat-v7:28.0.0'
implementation 'com.android.support.constraint:constraint-layout:1.1.3'
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'
implementation 'com.google.android.gms:play-services-location:16.0.0'}

清单：

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

Answer 1

永远无法保证您从getLastLocation() 获得位置。通常这意味着没有任何应用程序使用 GPS 来获取您的位置，因此没有任何缓存。

通常你所要做的就是打开谷歌地图或某个位置一旦被锁定就会被缓存的东西