Android Question Performance of redrawing markers.

[warayTek]

Hi! In my app every coordinate adds a marker (mpin.png) in the map. Below is a function to search a particular name, retrieve the coordinates, and change the marker (mpin2.png).
The way I change the marker is to clear the map first and add everything. This may slow down the app if the markers reach 1,000 coordinates. I appreciate any input. Thanks.

Private Sub SearchDialog2 'ON Panel3
    ASFloatingActionButton1.CloseMenu
    dialog.Initialize(Panel3)
'----------------------------------
Dim Cursor1 As Cursor
Cursor1 = SQL.ExecQuery("SELECT id,areaname,date,time,loc,result,controlno,bdate,gender,mobile,remarks  FROM survey")
Log("Size " & Cursor1.RowCount)
If Cursor1.RowCount < 1 Then
    Log("Empty records")
Else
    
    Dim v1,v2,MyCoor() As String
    nameSearchL.Clear
    coordL.Clear
    For i = 0 To Cursor1.RowCount - 1
    Cursor1.Position = i
    Log(Cursor1.GetString("loc") & " " & Cursor1.GetString("areaname"))
    v1 = Cursor1.GetString("areaname")   
    v2 = Cursor1.GetString("loc")
    nameSearchL.Add(v1)
    coordL.Add(v2)
    Next
    Cursor1.Close
End If

    '----------------------------------
    SearchTemplate.Initialize
    SearchTemplate.SetItems(nameSearchL)
    'SearchTemplate.PrefixOnly = True
    SearchTemplate.ItemHightlightColor = 1
    dialog.Title = "Search Member"
    SearchTemplate.Resize(90%x, 80%y) '
    Wait For (dialog.ShowTemplate(SearchTemplate, "", "", "CANCEL")) Complete (Result As Int)
    If Result = xui.DialogResponse_Positive Then
        Log(SearchTemplate.SelectedItem & " < ")
        For i = 0 To nameSearchL.Size-1
            If nameSearchL.Get(i) = SearchTemplate.SelectedItem.Trim Then
                Log(coordL.Get(i))
                MyCoor = Regex.Split(",",coordL.Get(i))
                Dim cp As CameraPosition
                cp.Initialize(MyCoor(0),MyCoor(1), 15)
                btnshowcoordinates_Click
                gmap.Clear
                Dim Pt1 As LatLng
                Dim m1 As Marker
                For i = 0 To coordLatList.Size-1
                    Log(coordLatList.Get(i) &"," & coordLonList.Get(i))
                    Pt1.Initialize(coordLatList.Get(i),coordLonList.Get(i))
                    
                    Log(Pt1.Latitude & " " & Pt1.Longitude)
                    If Pt1.Latitude = MyCoor(0).trim And Pt1.Longitude = MyCoor(1).trim Then
                        m1 = gmap.AddMarker3(MyCoor(0), MyCoor(1),"No. of voters: " & countVotersL.Get(i) , SetBitmapDensity(LoadBitmap(File.DirAssets, "mpin2.png")))
                        m1.Snippet = MyCoor(0) & " " & MyCoor(1)
                        Log("m1 " & m1.Snippet)
                    Else
                        m1 = gmap.AddMarker3(Pt1.Latitude, Pt1.Longitude,"No. of voters: " & countVotersL.Get(i) , SetBitmapDensity(LoadBitmap(File.DirAssets, "mpin.png")))
                        m1.Snippet = Pt1.Latitude & " " & Pt1.Longitude
                    End If
                Next
                Dim latlon As LatLng
                latlon.Initialize(MyCoor(0),MyCoor(1))
                radar.Initialize("",gmap,latlon)
                radar.withOuterCircleStrokeColor(Colors.ARGB(255,30,144,255))
                radar.withDistance(1)
                radar.startRadarAnimation
                gmap.AnimateCamera(cp)
            End If
        Next
        
    
    else if Result = xui.DialogResponse_Cancel Then

    End If
End Sub

 

[roumei]

You could store the markers in a global list (Dim m1 As Marker must be inside the loop) and access them if needed.
Use marker.Remove to delete it and add a new one with the new image.

 

[TILogistic]

?
Change Icon Marker

Private Sub SetIconMarker (TargetMarker As Marker, IconImage As B4XBitmap)
    Dim jBitmapDescriptor As JavaObject
    jBitmapDescriptor.InitializeStatic("com.google.android.gms.maps.model.BitmapDescriptorFactory")
    TargetMarker.As(JavaObject).RunMethod("setIcon", Array(jBitmapDescriptor.RunMethod("fromBitmap", Array(IconImage))))
End Sub

Change Position Marker

Dim MarkerPosition As LatLng
.
.
TargetMarker.Position = MarkerPosition

Rotate Marker

Private MarkerExtras1 As MarkerExtras 'library GoogleMapsExtras
.
.
'Marker Icon Rotation
MarkerExtras1.SetRotation(DefaultMarkerIcon, LastLocation.BearingTo(Location1))

 

[TILogistic]

If you want to move the marker with animation see this method

Tracking the position of an animation

I am moving an image with this code: iv1.Initialize("iv1") iv1.SetImage(im) MainForm.RootPane.AddNode(iv1,X_Pos,0,230,230) iv1.SetLayoutAnimated(Image_Speed,X_Pos,1670.0,230,230) Does anyone know how I can track the X and Y position of the image as it does it's animation? Thanks

www.b4x.com

 

[warayTek]

@TILogistic thank you! It saves me lots of headaches.