Question

我试图获得没有gps的纬度和经度，但它给了我null。但是当我在我的gps上时，它给出了lat long的正确值。我想通过wifi获得经纬度。我怎么解决这个问题？这是我的网络提供商代码：

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
            return null;
        } else {
            this.canGetLocation = true;
            if (isNetworkEnabled) {

                if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
                    // TODO: Consider calling
                    //    ActivityCompat#requestPermissions
                    // here to request the missing permissions, and then overriding
                    //   public void onRequestPermissionsResult(int requestCode, String[] permissions,
                    //                                          int[] grantResults)
                    // to handle the case where the user grants the permission. See the documentation
                    // for ActivityCompat#requestPermissions for more details.
                     return null;
                }
                //updates will be send according to these arguments
                locationManager.requestLocationUpdates(
                        LocationManager.NETWORK_PROVIDER,
                        MIN_TIME_BW_UPDATES,
                        MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
                Log.d("Network", "Network");
                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) {
                    if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
                        // TODO: Consider calling
                        //    ActivityCompat#requestPermissions
                        // here to request the missing permissions, and then overriding
                        //   public void onRequestPermissionsResult(int requestCode, String[] permissions,
                        //                                          int[] grantResults)
                        // to handle the case where the user grants the permission. See the documentation
                        // for ActivityCompat#requestPermissions for more details.
                        return null;
                    }
                    locationManager.requestLocationUpdates(
                            LocationManager.GPS_PROVIDER,
                            MIN_TIME_BW_UPDATES,
                            MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
                    Log.d("GPS Enabled", "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;
}

Answer 1

尝试使用WifiManager类。

如文档中所述，

此类提供用于管理Wi-Fi连接的所有方面的主要API。通过调用Private Sub Command15_Click() Dim oExcel As Object Dim oExcelWrkBk As Object Dim oExcelWrSht As Object Dim bExcelOpened As Boolean 'Start Excel On Error Resume Next Set oExcel = GetObject(, "Excel.Application") 'Bind to existing instance of Excel If Err.Number <> 0 Then 'Could not get instance of Excel, so create a new one Err.Clear On Error GoTo Error_Handler Set oExcel = CreateObject("excel.application") bExcelOpened = False Else 'Excel was already running bExcelOpened = True End If On Error GoTo Error_Handler oExcel.ScreenUpdating = False oExcel.Visible = False 'Keep Excel hidden until we are done with our manipulation 'Set oExcelWrkBk = oExcel.Workbooks.Add() 'Start a new workbook Set oExcelWrkBk = oExcel.Workbooks.Open("C:\test.xlsx") 'Open an existing Excel file Set oExcelWrSht = oExcelWrkBk.Sheets(1) 'which worksheet to work with 'Start copying over your form values to the Excel Spreadsheet 'Cells(8, 3) = 8th row, 3rd column oExcelWrSht.Cells(Rows.Count, 1).End(xlUp).Offset(1, 0) = Me.1 oExcelWrSht.Cells(Rows.Count, 2).End(xlUp).Offset(1, 0) = Me.2 oExcelWrSht.Cells(Rows.Count, 3).End(xlUp).Offset(1, 0) = Me.3 oExcelWrSht.Cells(Rows.Count, 4).End(xlUp).Offset(1, 0) = Me.4 oExcelWrSht.Cells(Rows.Count, 5).End(xlUp).Offset(1, 0) = Me.5 oExcelWrSht.Cells(Rows.Count, 6).End(xlUp).Offset(1, 0) = Me.6 oExcelWrSht.Cells(Rows.Count, 7).End(xlUp).Offset(1, 0) = Me.7 oExcelWrSht.Cells(Rows.Count, 8).End(xlUp).Offset(1, 0) = Me.8 oExcelWrSht.Cells(Rows.Count, 9).End(xlUp).Offset(1, 0) = Me.9 '... and so on ... oExcelWrSht.Range("A1").Select 'Return to the top of the page ' oExcelWrkBk.Close True, sFileName 'Save and close the generated workbook ' 'Close excel if is wasn't originally running ' If bExcelOpened = False Then ' oExcel.Quit ' End If Error_Handler_Exit: On Error Resume Next oExcel.Visible = True 'Make excel visible to the user Set oExcelWrSht = Nothing Set oExcelWrkBk = Nothing oExcel.ScreenUpdating = True Set oExcel = Nothing Exit Sub Error_Handler: MsgBox "The following error has occured" & vbCrLf & vbCrLf & _ "Error Number: " & Err.Number & vbCrLf & _ "Error Source: Export2XLS" & vbCrLf & _ "Error Description: " & Err.Description _ , vbOKOnly + vbCritical, "An Error has Occured!" Resume Error_Handler_Exit End Sub获取此类的实例。

这是执行Wi-Fi特定操作时使用的API。

另外，检查此SO帖子中给出的解决方案 - Android: How to Enable/Disable Wifi or Internet Connection Programmatically。希望它有所帮助！

Answer 2

请询问是否启用了网络提供程序。您可以使用以下命令检查network_provider是否已启用：locationManager.isProviderEnabled（LocationManager.NETWORK_PROVIDER）

您可以使用以下方式请求位置更新： locationManager.requestLocationUpdates（LocationManager.NETWORK_PROVIDER，0,0，this）;

您可以使用以下方式获取上一个已知位置：位置lastKnownLocation = locationManager.getLastKnownLocation（locationProvider）;

我在我的github repo中有一个示例应用程序，它曾经工作过。虽然没有最近的更新。这是链接：https://github.com/sauravpradhan/TrackMe-Ver-2.0

如果有帮助，请回来。

Answer 3

提供的链接包含所有信息。但是要从Lat获取位置，我们需要使用GeoCoder。

Geocoder g1= new Geocoder(getApplicationContext());
        List<Address> locale= null;
         String add = null;
        try
        {
            locale = g1.getFromLocation(location.getLatitude(), location.getLongitude(), 3);
        }
        catch(Exception e)
        {
        Log.d("Saurav_log", "Cant fetch address");
        }
    /*  finally
        {
         Log.d("Saurav_log", "Finally Exiting");
        }*/
           TextView textView2 = (TextView)findViewById(R.id.textView2);
           if(locale != null)
           {
              add =locale.get(0).getAddressLine(0);
           }
textView2.setText("From GPS:Actual Address \n"+add+locale.get(0).getLocality()+" \n"+locale.get(0).getCountryName()+" \n"+locale.get(0).getSubLocality());

LocationManager.NETWORK_PROVIDER无法正常工作

3 个答案: