Android Question B4XMap - draw a line

AlpVir

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I'm trying to draw a GPS track on a map created using the B4XMap library.
Documentation is poor and the only useful instruction I've found is the following (draw a line between 2 dots)
B4X: 
shapes.Add(coMapUtilities.instanceShapeLine(fcvMap,coMapUtilities.initShapeLine(coMapUtilities.initLatLng(48.856614,2.3522219),coMapUtilities.initLatLng(31.630000,-8.008889),fxui.Color_ARGB(128,255,0,255),1dip,"Paris to Marrakech")))

However I can not indicate latitude and longitude with variables :
Point 1: (Lt, Lg)
Point 2: (PrecLt, PrecLg)

Something like that :
B4X: 
shapes.Add(coMapUtilities.instanceShapeLine(fcvMap,coMapUtilities.initShapeLine(coMapUtilities.initLatLng(" & PrecLt & "," & PrecLg & "),coMapUtilities.initLatLng(" & Lg & "," & Lt & "),fxui.Color_ARGB(128,255,0,255),1dip,"test")))
 
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RB Smissaert

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AlpVir said:
Here is the project, expanded with all classes.
I marked with 4 apostrophes
''''
the points where I intervened.
Click to expand...
Had to sort some minor things out such as missing image files and not looked at it properly yet, but I think the problem is you are not doing something like this in Main:

B4X: 
Sub SetupMapdgOSM(tLLPatient As TMapLatLng, _
                  tLLCenter As TMapLatLng, _
                  BB As TMapBoxLatLng, _
                  iMapZoom As Int, _
                  iID As Int, _
                  bDrawCenterLines As Boolean)
    
    Dim tLLCurrentLocation As TMapLatLng

    'Lat and Lon of current patient or mapcenter
    '-------------------------------------------
    If tLLPatient = Null Then
        If tLLCenter = Null Then
            tLLCenter = MapUtilities.initLatLng(LocationLG.Latitude, LocationLG.Longitude)
        End If
        cMP.MapCenter = tLLCenter
    Else
        cMP.MapCenter = tLLPatient
    End If
    
    If tLLCenter = Null Then
        tLLCenter = cMP.MapCenter
    End If
    
    If cMP.MapCenter = Null Then
        tLLCurrentLocation = MapUtilities.initLatLng(Tracker.dCurrentLatitude, Tracker.dCurrentLongitude)
    Else
        tLLCurrentLocation = cMP.MapCenter
    End If
    
    If cMP.iEMIS_NUMBER <> -1 Then
        If iID = cMP.iEMIS_NUMBER Then
            SetCurrentPatientMarker(tLLCenter, False)
        End If
    Else
        'this happens after clearing the find patient dialog
        'change any current patient marker (filled circle) to a non-current patient marker (not filled)
        '----------------------------------------------------------------------------------------------
        For Each iKey As Int In mapMarkerCircles.Keys
            Dim cMSC As clsMapShapeCircle = mapMarkerCircles.Get(iKey)
            Dim tMSC As TMapShapeCircle = cMSC.get_Shape
            If tMSC.fFilled Then
                tMSC.fFilled = False
                cMSC.set_Shape(tMSC)
                Dim cMSC2 As clsMapShapeCircle = mapShapes.Get(iKey)
                Dim tMSC2 As TMapShapeCircle = cMSC2.get_Shape
                tMSC2.fFilled = False
                cMSC2.set_Shape(tMSC2)
                Exit
            End If
        Next
    End If
    
    If BB = Null Then
        If iMapZoom <> -1 Then
            iZoom = iMapZoom
        End If
    Else
        iZoom = MapUtilities.GetZoomToShowAll(tLLCenter, BB)
    End If
    
    fMap = MapUtilities.initMap( _
            tLLCenter, _                                  'alatLng (eg lat/lon of Current patient)
            iZoom, _                                     'aZoomLevel
            0, _                                        'aCompassDirection
            True, _                                        'aOffLineMode
            False, _                                    'aShowMenu
            cMP.bShowGrid, _                            'aShowGrid
            True, _                                        'aShowCentre
            False, _                                    'aShowLandMark
            False, _                                    'aShowCentreLatLng
            False, _                                    'aShowZoom
            False, _                                    'aShowScale
            False, _                                    'aShowCompass
            True, _                                        'aShowShapes
            mapShapes, _                                'aShapes (map)
            False, _                                    'aShowGPS
            False, _                                    'aFollowGPS
            MapUtilities.initGPS(tLLCurrentLocation, 0), _ 'aGPS
            False)                                       'bMultiShapeClick
            

    Sleep(10) '>>>>  this is needed to  avoid crash: fViewTiles in cvMap not initialized yet
    cvMap1.CenterLatLng = tLLCenter
    Sleep(10) '>>>>  this is needed to  avoid crash: fViewTiles in cvMap not initialized yet
    cvMap1.Map = fMap
    cvMap1.Draw
    
    If bDrawCenterLines Then
        Sleep(0)
        cvMap1.DrawCenterLines(Colors.Red, 1, cMP.bFullMapCenterLines, False)
        Sleep(0)
    End If
    
    If iID > -1 Then
        lblPatMap.Text = "  " & cMP.GetPatLabelString(-1)
    End If
    
End Sub

Have a look at that first.

RBS
 
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AlpVir

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I'm sorry but by inserting the SetupMapdgOSM sub the number of errors, unresolved references and possible unanswered questions increases.
Without a definitive solution I think I'll have to abandon this library which seemed to me very powerful and suitable for my purposes.
 
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RB Smissaert

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You can't just insert that Sub as it is very particular to my app.
The important thing is:

fMap = MapUtilities.initMap

As, unless I overlooked it, I didn't see that in your posted project.
Will have a look later and see if I can fix it.

RBS
 
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RB Smissaert

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RB Smissaert said:
You can't just insert that Sub as it is very particular to my app.
The important thing is:

fMap = MapUtilities.initMap

As, unless I overlooked it, I didn't see that in your posted project.
Will have a look later and see if I can fix it.

RBS
Click to expand...
The other thing is that it would be better to post a project that just shows the map you are dealing with and with a button that will do all the internet stuff.
At least we can then see that the map is showing OK and then concentrate on the troublesome other things.

RBS
 
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AlpVir

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As I assumed the original code was right but some instructions were put in the wrong places.
The map is now displayed correctly. And I used the library.
I just deleted the fcvmap_ready sub and changed the following code
B4X: 
        If JobDownload.Success Then
            If File.Exists(GlobalCartellaThisApp, TracciaWeb) = True Then
                File.Delete(GlobalCartellaThisApp, TracciaWeb)
            End If
            Dim out As OutputStream = File.OpenOutput(GlobalCartellaThisApp,  TracciaWeb, False)
            File.Copy2(JobDownload.GetInputStream, out)
            out.Close
            If File.Exists(GlobalCartellaThisApp, TracciaWeb) = True Then
                LoadShapes  (TracciaWeb)
                If shapes.Size>1 Then
                    fcvMap.TileServer="https://a.tile.openstreetmap.org/"   ' default
                    fcvMap.UserAgent="User-AgentMozilla/5.0 (Windows NT 10.0; Win64; x64; rv:108.0) Gecko/20100101 Firefox/108.0"
                    fMap=coMapUtilities.initMap(coMapUtilities.initLatLng(FineLt, FineLg),18,0,False,True,True,True,False,True,True, True, False,True, _
                                    shapes, _
                                    True,False,coMapUtilities.initGPS(coMapUtilities.initLatLng(0,0),0))
                    fcvMap.Map=fMap
                    fcvMap.draw
                Else
                    Log("No number one")
                End If
            End If
        End If
        JobDownload.Release
One last question: I used the default tile server https://a.tile.openstreetmap.org/
What other tile servers are available ?
Thanks again.
 
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RB Smissaert

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Are you saying it is all working OK now?
In that case: good news!

Not sure what other servers are available, never had a problem with the one that you and I use.
I changed the header as I had trouble with the previous one, see code:

B4X: 
    Try
        j.Initialize("", Me)
        j.Download("https://a.tile.openstreetmap.org/" & strTiles)
        
        'with this one downloading of tiles failed
        '-----------------------------------------
        'j.GetRequest.SetHeader("User-Agent","Mozilla/5.0 (Windows NT 6.1; WOW64; rv:27.0) Gecko/20100101 Firefox/27.0")
        j.GetRequest.SetHeader("User-Agent", "Mozilla/5.0 (iPad; U; CPU OS 3_2 like Mac OS X; en-us) AppleWebKit/531.21.10 (KHTML, like Gecko) Version/4.0.4 Mobile/7B334b Safari/531.21.102011-10-16 20:23:10")

RBS
 
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AlpVir

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AlpVir

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Longtime User
The URL is now reactivated.
Yes, using the B4XMap library I display a GPS track (see attached screenshot) with the instruction
B4X: 
shapes.Add(coMapUtilities.instanceShapeLine(fcvMap,coMapUtilities.initShapeLine(coMapUtilities.initLatLng( PrecLT,PrecLg),coMapUtilities.initLatLng(Lt, Lg),Colors.ARGB(128,255,0,255),3dip,"")))
The idea would be to give the user the possibility to choose between different tile-servers. Now I use the default one with instructions
B4X: 
fcvMap.TileServer="https://a.tile.openstreetmap.org/"
fcvMap.UserAgent="User-Agent/Mozilla/5.0 (iPad; U; CPU OS 3_2 like Mac OS X; en-us) AppleWebKit/531.21.10 (KHTML, like Gecko) Version/4.0.4 Mobile/7B334b Safari/ 531.21.102011-10-16 20:23:10"
and it doesn't seem to me that the B4XMap library provides the possibility of using the getTileFromInternet sub.
 

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RB Smissaert

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> and it doesn't seem to me that the B4XMap library provides the possibility of using the getTileFromInternet sub.

Works OK here.
What error/problem are you seeing?

RBS
 
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AlpVir

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Longtime User
There are currently no errors in my app and the GPS track is displayed correctly. @ RB Smissaert : Thanks for your help.
My previous post was addressed to @TILogistic who pointed out the possibility of using another tile-server.
However I don't know how to insert the Google tile-server inside the B4XMap library.
I specify that I would like to continue using this library and not the class modules.
 
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RB Smissaert

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Nice to hear it is all working OK.
Not sure what you mean with Google tile-server.
I thought that the B4XMap library/classes only worked with OSM.
I very much prefer to use the classes for various reasons, but it is easy to make a library from the classes and also
vice-versa to get the classes from the library. Just unzip the library.

RBS
 
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hasanaydin52

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i cant see TileServer in cvMap class.
 
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papajds

Member
Hi,

I try to draw a line on the map, but nothing is displayed, and no error...
I copied, to test a line which works when launching the program, but in a button, it does not work.
I think something is missing...but I can't find it

can anyone help me?

Thanks.

add line: 
Public Sub  Button9_Click
    Dim shapes As List
    shapes.Initialize
            shapes.Add(coMapUtilities.instanceShapeLine(fcvMap,coMapUtilities.initShapeLine(coMapUtilities.initLatLng(51.5073509,-0.1277583),coMapUtilities.initLatLng(48.856614,2.3522219),fxui.Color_Blue,4dip,"London to Paris")))
        fcvMap.draw
    
End Sub
 
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papajds

Member
Hi,
i found my mistake:

2 lines removed and it's ok


ok: 
Public Sub  Button9_Click
            shapes.Add(coMapUtilities.instanceShapeLine(fcvMap,coMapUtilities.initShapeLine(coMapUtilities.initLatLng(51.5073509,-0.1277583),coMapUtilities.initLatLng(48.856614,2.3522219),fxui.Color_Blue,4dip,"London to Paris")))
        fcvMap.draw
    
End Sub
 
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