iOS Question problem with update location


Active Member
Licensed User
hello all I used location in iphone 5s
when I test loction not update when change ..
only update 2 time or 3 times after nothing
what problem?
this code sir Erel
'Code module
#Region  Project Attributes
    #ApplicationLabel: B4i Example
    #Version: 1.0.0
    'Orientation possible values: Portrait, LandscapeLeft, LandscapeRight and PortraitUpsideDown
    #iPhoneOrientations: Portrait, LandscapeLeft, LandscapeRight
    #iPadOrientations: Portrait, LandscapeLeft, LandscapeRight, PortraitUpsideDown
    #PlistExtra:<key>NSLocationWhenInUseUsageDescription</key><string>Used to display the current navigation data.</string>
    #PlistExtra:<key>NSLocationUsageDescription</key><string>Used to display the current navigation data.</string>
#End Region

Sub Process_Globals
    'These global variables will be declared once when the application starts.
    'Public variables can be accessed from all modules.
    Public App As Application
    Public NavControl As NavigationController
    Private Page1 As Page
    Private LocManager As LocationManager
    Private lblAccuracy As Label
    Private lblAltitude As Label
    Private lblBearing As Label
    Private lblEnable As Label
    Private lblHeading As Label
    Private lblLL As Label
    Private lblSpeed As Label
    Private lblTime As Label

End Sub

Private Sub Application_Start (Nav As NavigationController)
    NavControl = Nav
    Page1.RootPanel.Color = Colors.White

End Sub
Private Sub LocManager_AuthorizationStatusChanged (Status As Int)
    lblEnable.Visible = (LocManager.AuthorizationStatus = LocManager.AUTHORIZATION_DENIED _
        Or LocManager.AuthorizationStatus = LocManager.AUTHORIZATION_RESTRICTED)
End Sub

Private Sub StartLocationUpdates
    'if the user allowed us to use the location service or if we never asked the user before then we call LocationManager.Start.
    If LocManager.IsAuthorized Or LocManager.AuthorizationStatus = LocManager.AUTHORIZATION_NOT_DETERMINED Then
    End If
End Sub

Private Sub Application_Foreground
End Sub

Private Sub Application_Background
End Sub

Private Sub LocManager_HeadingChanged (MagneticHeading As Double, TrueHeading As Double)
    If TrueHeading >= 0 Then
        lblHeading.Text = NumberFormat(TrueHeading, 1, 0) & Chr(176) & " (true north)"
        lblHeading.Text = NumberFormat(MagneticHeading, 1, 0) & Chr(176) & " (magnetic)"
    End If
End Sub
Sub LocManager_AllowCalibration As Boolean
End Sub

Private Sub LocManager_LocationError
    Log("Error: " & LastException.Description)
End Sub

Private Sub LocManager_LocationChanged (Location1 As Location)
    If Location1.VerticalAccuracy >= 0 Then
        lblAltitude.Text =    Location1.Altitude', 1, 1) & "m"
        lblAltitude.Text = "N/A"
    End If
    lblBearing.Text = ValueOrNA (Location1.Bearing, 1, Chr(176))
    If Location1.Accuracy >= 0 Then
        lblLL.Text =Location1.Latitude & "/" & Location1.Longitude' NumberFormat(Location1.Latitude, 2, 4) & " / " & NumberFormat(Location1.Longitude, 2, 4)
        lblLL.Text = "N/A"
    End If
    lblSpeed.Text = ValueOrNA(Location1.Speed, 1, "m/s")
    lblTime.Text = DateTime.Time(Location1.Time)
    lblAccuracy.Text = ValueOrNA(Location1.Accuracy, 2, "m")
End Sub

Private Sub ValueOrNA(value As Double, NumberOfFractions As Int, unit As String) As String
    If value < 0 Then
        Return "N/A"
        Return NumberFormat(value, 1, NumberOfFractions) & unit
    End If
End Sub

Private Sub Page1_Resize(Width As Int, Height As Int)
End Sub


B4X founder
Staff member
Licensed User
Longtime User
I already..but not update
I try outdoor same not update
not change
In that case there is no need to post it.

If the LocationChanged event was raised then I expect it to work. Run your app in release mode and check it over a larger distance. Maybe the GPS reception is weak.
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