Problem calling a Sub in another form

[vitorjol]

Hello.

I have 2 forms (Form1 and Form2). When i call the Sub placed in form1 from
form2, i get the error "object reference not set to an instance of an object"
!
What can i do to solve the problem?

Thanks

[rowe_newsgroups]

Please post the code that calls the sub.

Thanks,

Seth Rowe

vitorjol wrote:

Hello.

I have 2 forms (Form1 and Form2). When i call the Sub placed in form1 from
form2, i get the error "object reference not set to an instance of an object"
!
What can i do to solve the problem?

Thanks

[vitorjol]

Here is the code:

' the code in form2
Private Sub DataGridView1_R owHeaderMouseCl ick(ByVal sender As Object, ByVal
e As System.Windows. Forms.DataGridV iewCellMouseEve ntArgs) Handles
DataGridView1.R owHeaderMouseCl ick
dim exitvar as Integer
exitvar = DataGridView1.R ows(e.RowIndex) .Cells(0).Value
Dim ff As New Form1
ff.BringToFront ()
ff.soumavez(exi tvar) ' this is the call to the sub in Form1
End Sub

"rowe_newsgroup s" wrote:

Please post the code that calls the sub.

Thanks,

Seth Rowe

vitorjol wrote:

Hello.

I have 2 forms (Form1 and Form2). When i call the Sub placed in form1 from
form2, i get the error "object reference not set to an instance of an object"
!
What can i do to solve the problem?

Thanks

[rowe_newsgroups]

Looks like it should work, when you step through the code where does
the exception occur? If the error occurs in somewhere other than this
sub please post that code too. Also what does "soumavez" mean?

Thanks,

Seth Rowe
vitorjol wrote:

Here is the code:

' the code in form2
Private Sub DataGridView1_R owHeaderMouseCl ick(ByVal sender As Object, ByVal
e As System.Windows. Forms.DataGridV iewCellMouseEve ntArgs) Handles
DataGridView1.R owHeaderMouseCl ick
dim exitvar as Integer
exitvar = DataGridView1.R ows(e.RowIndex) .Cells(0).Value
Dim ff As New Form1
ff.BringToFront ()
ff.soumavez(exi tvar) ' this is the call to the sub in Form1
End Sub

"rowe_newsgroup s" wrote:

Please post the code that calls the sub.

Thanks,

Seth Rowe

vitorjol wrote:

Hello.
>
I have 2 forms (Form1 and Form2). When i call the Sub placed in form1 from
form2, i get the error "object reference not set to an instance of an object"
!
What can i do to solve the problem?
>
Thanks

[vitorjol]

ok....the name "soumavez" its a name that i called to the Sub...End Sub.

i put here the code of Sub(its about the Mapguide ActiveX to show a map in
VB). I'll send there to Sub in the other form the id of a polygon on the map,
and then the Sub localize the polygon and zoom the place!!!

Code of the Sub "soumavez" in the Form1:

Public Sub soumavez(ByVal varin As Integer)
' --->"varin" its the var that i send from Form2!!!
' --->"mgmap" its the name of the control (mapguide activex)
Try
Dim pubmapsel As MGMapControl.MG Selection
Dim pubvar2 As MGMapControl.MG MapLayer
Dim pubmapobjectos As MGMapControl.MG Collection
Dim pubmapobj As MGMapControl.MG MapObject
pubmapsel = mgmap.getSelect ion()
pubvar2 = mgmap.getMapLay er("SIG")
pubmapobjectos = mgmap.createObj ect("MGCollecti on")
pubmapobj = pubvar2.getMapO bject(varin)
pubmapobjectos. add(pubmapobj)
pubmapsel.addOb jectsEx(pubmapo bjectos, False)
mgmap.zoomSelec ted()
mgmap.zoomScale (mgmap.getLat() , mgmap.getLon(), 1500)
mgmap.refresh()
Catch ex As Exception
MessageBox.Show (ex.Message, "Erro", MessageBoxButto ns.OK,
MessageBoxIcon. Error)
End Try
End Sub
"rowe_newsgroup s" wrote:

Looks like it should work, when you step through the code where does
the exception occur? If the error occurs in somewhere other than this
sub please post that code too. Also what does "soumavez" mean?

Thanks,

Seth Rowe
vitorjol wrote:

Here is the code:

' the code in form2
Private Sub DataGridView1_R owHeaderMouseCl ick(ByVal sender As Object, ByVal
e As System.Windows. Forms.DataGridV iewCellMouseEve ntArgs) Handles
DataGridView1.R owHeaderMouseCl ick
dim exitvar as Integer
exitvar = DataGridView1.R ows(e.RowIndex) .Cells(0).Value
Dim ff As New Form1
ff.BringToFront ()
ff.soumavez(exi tvar) ' this is the call to the sub in Form1
End Sub

"rowe_newsgroup s" wrote:

Please post the code that calls the sub.
>
Thanks,
>
Seth Rowe
>
vitorjol wrote:
Hello.

I have 2 forms (Form1 and Form2). When i call the Sub placed in form1 from
form2, i get the error "object reference not set to an instance of an object"
!
What can i do to solve the problem?

Thanks
>
>

[rowe_newsgroups]

ok....the name "soumavez" its a name that i called to the Sub...End Sub.

It looked like a foreign langauge to me (is it?), so I was just making
sure it was a protected keyword in a foreign language edition of visual
studio.

Anyways, I have to apologize - my "visual" debugging skills must be
lacking today, as I still don't see anything obviously wrong. Which
line of the code raises the exception?

Thanks,

Seth Rowe
vitorjol wrote:

>
i put here the code of Sub(its about the Mapguide ActiveX to show a map in
VB). I'll send there to Sub in the other form the id of a polygon on the map,
and then the Sub localize the polygon and zoom the place!!!

Code of the Sub "soumavez" in the Form1:

Public Sub soumavez(ByVal varin As Integer)
' --->"varin" its the var that i send from Form2!!!
' --->"mgmap" its the name of the control (mapguide activex)
Try
Dim pubmapsel As MGMapControl.MG Selection
Dim pubvar2 As MGMapControl.MG MapLayer
Dim pubmapobjectos As MGMapControl.MG Collection
Dim pubmapobj As MGMapControl.MG MapObject
pubmapsel = mgmap.getSelect ion()
pubvar2 = mgmap.getMapLay er("SIG")
pubmapobjectos = mgmap.createObj ect("MGCollecti on")
pubmapobj = pubvar2.getMapO bject(varin)
pubmapobjectos. add(pubmapobj)
pubmapsel.addOb jectsEx(pubmapo bjectos, False)
mgmap.zoomSelec ted()
mgmap.zoomScale (mgmap.getLat() , mgmap.getLon(), 1500)
mgmap.refresh()
Catch ex As Exception
MessageBox.Show (ex.Message, "Erro", MessageBoxButto ns.OK,
MessageBoxIcon. Error)
End Try
End Sub
"rowe_newsgroup s" wrote:

Looks like it should work, when you step through the code where does
the exception occur? If the error occurs in somewhere other than this
sub please post that code too. Also what does "soumavez" mean?

Thanks,

Seth Rowe
vitorjol wrote:

Here is the code:
>
' the code in form2
Private Sub DataGridView1_R owHeaderMouseCl ick(ByVal sender As Object, ByVal
e As System.Windows. Forms.DataGridV iewCellMouseEve ntArgs) Handles
DataGridView1.R owHeaderMouseCl ick
dim exitvar as Integer
exitvar = DataGridView1.R ows(e.RowIndex) .Cells(0).Value
Dim ff As New Form1
ff.BringToFront ()
ff.soumavez(exi tvar) ' this is the call to the sub in Form1
End Sub
>
"rowe_newsgroup s" wrote:
>
Please post the code that calls the sub.

Thanks,

Seth Rowe

vitorjol wrote:
Hello.
>
I have 2 forms (Form1 and Form2). When i call the Sub placed in form1 from
form2, i get the error "object reference not set to an instance of an object"
!
What can i do to solve the problem?
>
Thanks

[vitorjol]

Yes....im portuguese....b ut I love America!!!!!

i forgot to tell U the line with the problem!!!Sorry

So, the problem "object reference not set to an instance of an object"
occurs in the line >>pubmapobj = pubvar2.getMapO bject(varin)

Thanks
"rowe_newsgroup s" wrote:

ok....the name "soumavez" its a name that i called to the Sub...End Sub.

It looked like a foreign langauge to me (is it?), so I was just making
sure it was a protected keyword in a foreign language edition of visual
studio.

Anyways, I have to apologize - my "visual" debugging skills must be
lacking today, as I still don't see anything obviously wrong. Which
line of the code raises the exception?

Thanks,

Seth Rowe
vitorjol wrote:

i put here the code of Sub(its about the Mapguide ActiveX to show a map in
VB). I'll send there to Sub in the other form the id of a polygon on the map,
and then the Sub localize the polygon and zoom the place!!!

Code of the Sub "soumavez" in the Form1:

Public Sub soumavez(ByVal varin As Integer)
' --->"varin" its the var that i send from Form2!!!
' --->"mgmap" its the name of the control (mapguide activex)
Try
Dim pubmapsel As MGMapControl.MG Selection
Dim pubvar2 As MGMapControl.MG MapLayer
Dim pubmapobjectos As MGMapControl.MG Collection
Dim pubmapobj As MGMapControl.MG MapObject
pubmapsel = mgmap.getSelect ion()
pubvar2 = mgmap.getMapLay er("SIG")
pubmapobjectos = mgmap.createObj ect("MGCollecti on")
pubmapobj = pubvar2.getMapO bject(varin)
pubmapobjectos. add(pubmapobj)
pubmapsel.addOb jectsEx(pubmapo bjectos, False)
mgmap.zoomSelec ted()
mgmap.zoomScale (mgmap.getLat() , mgmap.getLon(), 1500)
mgmap.refresh()
Catch ex As Exception
MessageBox.Show (ex.Message, "Erro", MessageBoxButto ns.OK,
MessageBoxIcon. Error)
End Try
End Sub
"rowe_newsgroup s" wrote:

Looks like it should work, when you step through the code where does
the exception occur? If the error occurs in somewhere other than this
sub please post that code too. Also what does "soumavez" mean?
>
Thanks,
>
Seth Rowe
>
>
vitorjol wrote:
Here is the code:

' the code in form2
Private Sub DataGridView1_R owHeaderMouseCl ick(ByVal sender As Object, ByVal
e As System.Windows. Forms.DataGridV iewCellMouseEve ntArgs) Handles
DataGridView1.R owHeaderMouseCl ick
dim exitvar as Integer
exitvar = DataGridView1.R ows(e.RowIndex) .Cells(0).Value
Dim ff As New Form1
ff.BringToFront ()
ff.soumavez(exi tvar) ' this is the call to the sub in Form1
End Sub

"rowe_newsgroup s" wrote:

Please post the code that calls the sub.
>
Thanks,
>
Seth Rowe
>
vitorjol wrote:
Hello.

I have 2 forms (Form1 and Form2). When i call the Sub placed in form1 from
form2, i get the error "object reference not set to an instance of an object"
!
What can i do to solve the problem?

Thanks
>
>
>
>

[rowe_newsgroups]

Hmm. The "object reference not set to an instance of an object"
exception is raised when you try to use an object that doesn't exist
yet, like if you left out the New keyword. However, everything looks
alright to me. The only thing I would try (outside of praying that
someone else happens on this thread and sees what we're missing!) is to
change this line:

>pubmapobj = pubvar2.getMapO bject(varin)

To this:

pubmapobj = MGMapControl.MG MapLayer.getMap Object(varin)

That will take the pubvar2 variable out of the equation. Note, you may
also try throwing the "New" keyword into that line, I'm not sure if
you do or don't need it.

Hope that helps,

Seth Rowe

vitorjol wrote:

Yes....im portuguese....b ut I love America!!!!!

i forgot to tell U the line with the problem!!!Sorry

So, the problem "object reference not set to an instance of an object"
occurs in the line >>pubmapobj = pubvar2.getMapO bject(varin)

Thanks
"rowe_newsgroup s" wrote:

ok....the name "soumavez" its a name that i called to the Sub...End Sub.

It looked like a foreign langauge to me (is it?), so I was just making
sure it was a protected keyword in a foreign language edition of visual
studio.

Anyways, I have to apologize - my "visual" debugging skills must be
lacking today, as I still don't see anything obviously wrong. Which
line of the code raises the exception?

Thanks,

Seth Rowe
vitorjol wrote:

>
i put here the code of Sub(its about the Mapguide ActiveX to show a map in
VB). I'll send there to Sub in the other form the id of a polygon on the map,
and then the Sub localize the polygon and zoom the place!!!
>
Code of the Sub "soumavez" in the Form1:
>
Public Sub soumavez(ByVal varin As Integer)
' --->"varin" its the var that i send from Form2!!!
' --->"mgmap" its the name of the control (mapguide activex)
Try
Dim pubmapsel As MGMapControl.MG Selection
Dim pubvar2 As MGMapControl.MG MapLayer
Dim pubmapobjectos As MGMapControl.MG Collection
Dim pubmapobj As MGMapControl.MG MapObject
pubmapsel = mgmap.getSelect ion()
pubvar2 = mgmap.getMapLay er("SIG")
pubmapobjectos = mgmap.createObj ect("MGCollecti on")
pubmapobj = pubvar2.getMapO bject(varin)
pubmapobjectos. add(pubmapobj)
pubmapsel.addOb jectsEx(pubmapo bjectos, False)
mgmap.zoomSelec ted()
mgmap.zoomScale (mgmap.getLat() , mgmap.getLon(), 1500)
mgmap.refresh()
Catch ex As Exception
MessageBox.Show (ex.Message, "Erro", MessageBoxButto ns.OK,
MessageBoxIcon. Error)
End Try
End Sub
>
>
"rowe_newsgroup s" wrote:
>
Looks like it should work, when you step through the code where does
the exception occur? If the error occurs in somewhere other than this
sub please post that code too. Also what does "soumavez" mean?

Thanks,

Seth Rowe


vitorjol wrote:
Here is the code:
>
' the code in form2
Private Sub DataGridView1_R owHeaderMouseCl ick(ByVal sender As Object, ByVal
e As System.Windows. Forms.DataGridV iewCellMouseEve ntArgs) Handles
DataGridView1.R owHeaderMouseCl ick
dim exitvar as Integer
exitvar = DataGridView1.R ows(e.RowIndex) .Cells(0).Value
Dim ff As New Form1
ff.BringToFront ()
ff.soumavez(exi tvar) ' this is the call to the sub in Form1
End Sub
>
"rowe_newsgroup s" wrote:
>
Please post the code that calls the sub.

Thanks,

Seth Rowe

vitorjol wrote:
Hello.
>
I have 2 forms (Form1 and Form2). When i call the Sub placed in form1 from
form2, i get the error "object reference not set to an instance of an object"
!
What can i do to solve the problem?
>
Thanks

[GhostInAK]

Hello rowe_newsgroups ,

Your solutuion would not work. MGMapControl is the namespace.. MGMapLayer
is the type. getMapObject is not static (shared).
pubvar2 (GEEZ! Use some better freakin names next time wouldja, OP!) is
supposed to grab a reference to a specific map layer.

You are correct in that the OP is trying to use an object that is null.

OP: Check your MWF, make sure you have a layer actually called "SIG". Also,
ZoomSelected is a terrible way to get to an object. First, the selection
will only succeed if the object is visible at your current zoom scale. Second,
MapGuide is notorious for busystate collisions.

-Boo

Hmm. The "object reference not set to an instance of an object"
exception is raised when you try to use an object that doesn't exist
yet, like if you left out the New keyword. However, everything looks
alright to me. The only thing I would try (outside of praying that
someone else happens on this thread and sees what we're missing!) is
to change this line:

>pubmapobj = pubvar2.getMapO bject(varin)

To this:

pubmapobj = MGMapControl.MG MapLayer.getMap Object(varin)

That will take the pubvar2 variable out of the equation. Note, you may
also try throwing the "New" keyword into that line, I'm not sure if
you do or don't need it.

Hope that helps,

Seth Rowe

vitorjol wrote:

>Yes....im portuguese....b ut I love America!!!!!

i forgot to tell U the line with the problem!!!Sorry

So, the problem "object reference not set to an instance of an
object" occurs in the line >>pubmapobj = pubvar2.getMapO bject(varin)

Thanks

"rowe_newsgrou ps" wrote:

>>>ok....the name "soumavez" its a name that i called to the Sub...End
Sub.

It looked like a foreign langauge to me (is it?), so I was just
making sure it was a protected keyword in a foreign language edition
of visual studio.

Anyways, I have to apologize - my "visual" debugging skills must be
lacking today, as I still don't see anything obviously wrong. Which
line of the code raises the exception?

Thanks,

Seth Rowe

vitorjol wrote:

i put here the code of Sub(its about the Mapguide ActiveX to show a
map in VB). I'll send there to Sub in the other form the id of a
polygon on the map, and then the Sub localize the polygon and zoom
the place!!!

Code of the Sub "soumavez" in the Form1:

Public Sub soumavez(ByVal varin As Integer)
' --->"varin" its the var that i send from Form2!!!
' --->"mgmap" its the name of the control (mapguide activex)
Try
Dim pubmapsel As MGMapControl.MG Selection
Dim pubvar2 As MGMapControl.MG MapLayer
Dim pubmapobjectos As MGMapControl.MG Collection
Dim pubmapobj As MGMapControl.MG MapObject
pubmapsel = mgmap.getSelect ion()
pubvar2 = mgmap.getMapLay er("SIG")
pubmapobject os = mgmap.createObj ect("MGCollecti on")
pubmapobj = pubvar2.getMapO bject(varin)
pubmapobject os.add(pubmapob j)
pubmapsel.ad dObjectsEx(pubm apobjectos, False)
mgmap.zoomSe lected()
mgmap.zoomSc ale(mgmap.getLa t(), mgmap.getLon(), 1500)
mgmap.refres h()
Catch ex As Exception
MessageBox.S how(ex.Message, "Erro", MessageBoxButto ns.OK,
MessageBoxIc on.Error)
End Try
End Sub
"rowe_newsgr oups" wrote:

Looks like it should work, when you step through the code where
does the exception occur? If the error occurs in somewhere other
than this sub please post that code too. Also what does "soumavez"
mean?
>
Thanks,
>
Seth Rowe
>
vitorjol wrote:
>
>Here is the code:
>>
>' the code in form2
>Private Sub DataGridView1_R owHeaderMouseCl ick(ByVal sender As
>Object, ByVal
>e As System.Windows. Forms.DataGridV iewCellMouseEve ntArgs) Handles
>DataGridVi ew1.RowHeaderMo useClick
>dim exitvar as Integer
>exitvar = DataGridView1.R ows(e.RowIndex) .Cells(0).Value
>Dim ff As New Form1
>ff.BringTo Front()
>ff.soumave z(exitvar) ' this is the call to the sub in Form1
>End Sub
>"rowe_news groups" wrote:
>>
>>Please post the code that calls the sub.
>>>
>>Thanks,
>>>
>>Seth Rowe
>>>
>>vitorjo l wrote:
>>>
>>>Hello.
>>>>
>>>I have 2 forms (Form1 and Form2). When i call the Sub placed in
>>>form1 from
>>>form2, i get the error "object reference not set to an instance
>>>of an object"
>>>!
>>>What can i do to solve the problem?
>>>Thanks
>>>>

[Daniel Bloch]

What I see is that you do not show the form BringToFront does not make
a control a top-level control, and it does not raise the Paint event.

So with the knowledge of the last post, try following

- Check, if you can run the sub from form2 alone. Implement a button to
show what you want and make a test like this.
- If this does not work, first correct the sub until you are able to
let it run.
- After that, first show the new form and then let sub run from
form1...

Daniel