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vb 2008 drawline not working in Vista

What am I missing here?

I am using Visual Basic Express 2008.

I have a working pilot logbook and flight planning application, which was written, compiled, and functions well in Windows XP on my old PC.

The application uses e.graphics.drawline, e.graphics.drawcircle, e.graphics.drawarc, e.graphics.drawellipse and e.graphics.drawrectangle to draw a simple flight plan chart.

When I compile the code and run it on my new laptop (Sony Vaio VGN-NS15G) none of the lines, arcs, circles or rectangles appear. There are no runtime errors.

The rest of the programme runs fine on the laptop. It is just the graphics functions that are ignored so I am assuming it is a result of some setting or switch that I have missed to make the graphics visible on the Vista laptop.

What am I overlooking?

ASKER CERTIFIED SOLUTION

oobayly

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bantamb20

ASKER

I am painting to the form using the form_paint subroutine, not OnPaint.
This process works fine in the XP environment.

First the DrawAll sub is executed, which contains the various subs to draw each portion of the flight plan. This enabled me to debug the earlier version easily, and allows users to choose various overlays, add text for latitude and longitude, names of places and so on.
All this worked fine in XP.

I have checked with breakpoints, and yes it is executing all the code.

I have attached the form_paint code, the DrawAll sub, and the simplest of the other subs it calls, the DrawBorder sub.

Your suggestions of using OnPaint and drawing to a bitmap are good ones. I will investigate and see what's involved to change the present method of drawing the plan.

I am going flying today so won't be able to complete the task now, but will get on to it asap.

Cheers


 
    ' ==================================================================
    '  paint this form and draw the flight track and other little bits
    ' ------------------------------------------------------------------
    Private Sub frmShowMap_Paint(ByVal sender As Object, ByVal e As  _
    System.Windows.Forms.PaintEventArgs) Handles MyBase.Paint
 
        Try
 
            If bGo Then
                Cursor = Cursors.WaitCursor
                DrawAll(e)
            End If
 
        Catch ex As Exception
            Cursor = Cursors.Default
            MsgBox(ex.Message)
        End Try
 
        Cursor = Cursors.Default
 
    End Sub
 
 
 
    ' ==================================================================
    '  draw background map, aircraft tracks, zone, area boundaries,text 
    ' ------------------------------------------------------------------
    Private Sub DrawAll(ByVal e As PaintEventArgs)
 
        Try
            If bGo = True Then
                bGo = False
 
                ' draw debugging grid
                DrawGraticule(e)
 
                ' draw border around map area
                DrawBorder(e)
 
                ' draw nz background map
                DrawNZMap(e, bShowMap)
 
                ' draw latitude and longitude grid
                DrawGrid(e, bShowGrid)
 
 
                ' draw airport control zones CTR. if files exist and zones in area, draw them
                If CTZFindFiles() And CTZonesInArea() Then CTZonesDraw(e, bShowCTZones)
 
                ' draw danger areas 
                DrawDanger(e)
 
                ' draw temporary airspace restrictions
                DrawTempo(e)
 
                ' draw tracks and aerodromes and waypoints
                DrawTracks(e, bShowTrack)
 
                ' write mag heading or distance and leg time text along track line 
                DrawText(e, bShowText)
 
            End If
 
        Catch ex As Exception
            MsgBox(ex.Message & " drawmap error")
        End Try
 
    End Sub
 
 
 
    ' ==========================================================
    '  draw border around map
    ' ----------------------------------------------------------
    Private Sub DrawBorder(ByVal e As PaintEventArgs)
        Try
            e.Graphics.DrawRectangle(Pens.Black, 2, 2, MEWIDTHH, MEHEIGHT)
        Catch ex As Exception
            MsgBox(ex.Message & " --- drawborder")
        End Try
 
    End Sub

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oobayly

Now that's a hobby/job I wouldn't mind having.

If the Paint event doesn't do the job, I very much doubt that the OnPaint override would do the job. I can only imagine it's an effect of the Aero interface. Not that I've seen any mention of there being issues with drawing on a form's graphics object in Vista.

bantamb20

ASKER

I have re-written the map display section to draw to a bitmap and display it on a picture box. It works well thanks

[The flying (microlights) and the coding are both hobbies . . . one more expensive than the other]

bantamb20

ASKER

The programme now works well in Vista as well as XP with this bitmap solution, it's a sunny day ... time to go flying and turn some petrol into noise . . . cheers