使用 NetWork Provider 获取 LatLong答案

【问题标题】：Getting LatLong using NetWork Provider使用 NetWork Provider 获取 LatLong
【发布时间】：2016-02-09 09:07:52
【问题描述】：

我正在使用下面的代码来获取 LatLong，我也在使用 NetWorkProvider 来获取 LatLong：

下面的代码工作正常：

        // if GPS Enabled get lat/long using GPS Services
        if (isGPSEnabled) {
            if (mLocation == null) {
                mLocationManager.requestLocationUpdates(
                        LocationManager.GPS_PROVIDER,
                        5000,
                        5000, this);
                if (mLocationManager != null) {
                    mLocation = mLocationManager
                            .getLastKnownLocation(LocationManager.GPS_PROVIDER);
                    if (mLocation != null) {

                        //Called here...
                        onLocationChanged(mLocation);

                    }
                }
            }
        }

但是，当我使用下面的代码时：

if (isNetworkEnabled) {
            mLocationManager.requestLocationUpdates(
                    LocationManager.NETWORK_PROVIDER,
                    5000,
                    5000, MainActivity.this);

            if (mLocationManager != null) {
                mLocation = mLocationManager
                        .getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
                if (mLocation != null) {
                    onLocationChanged(mLocation);
                }
            }
        }

我正在获取 mLocation null。可能是什么原因？

【问题讨论】：

标签： android google-maps location latitude-longitude

【解决方案1】：

请尝试下面的代码。

public Location getLocation() {
try {
    locationManager = (LocationManager) mContext
            .getSystemService(LOCATION_SERVICE);

    // getting GPS status
    isGPSEnabled = locationManager
            .isProviderEnabled(LocationManager.GPS_PROVIDER);

    // getting network status
    isNetworkEnabled = locationManager
            .isProviderEnabled(LocationManager.NETWORK_PROVIDER);

    if (!isGPSEnabled && !isNetworkEnabled) {
        // no network provider is enabled
    } else {
        this.canGetLocation = true;
        if (isNetworkEnabled) {
            locationManager.requestLocationUpdates(
                    LocationManager.NETWORK_PROVIDER,
                    MIN_TIME_BW_UPDATES,
                    MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
            Log.d("Network", "Network Enabled");
            if (locationManager != null) {
                location = locationManager
                        .getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
                if (location != null) {
                    latitude = location.getLatitude();
                    longitude = location.getLongitude();
                }
            }
        }
        // if GPS Enabled get lat/long using GPS Services
        if (isGPSEnabled) {
            if (location == null) {
                locationManager.requestLocationUpdates(
                        LocationManager.GPS_PROVIDER,
                        MIN_TIME_BW_UPDATES,
                        MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
                Log.d("GPS", "GPS Enabled");
                if (locationManager != null) {
                    location = locationManager
                            .getLastKnownLocation(LocationManager.GPS_PROVIDER);
                    if (location != null) {
                        latitude = location.getLatitude();
                        longitude = location.getLongitude();
                    }
                }
            }
        }
    }

} catch (Exception e) {
    e.printStackTrace();
}

return location;
}

【讨论】：

同样的问题，获取位置为空，当我为 isGPSEnableb 提交 if 循环时，但它可以使用 GPS 取消注释和检查。

【解决方案2】：

检查AndroidManifest.xml中是否存在权限：

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

<uses-permission android:name="android.permission.READ_PHONE_STATE" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />

【讨论】：