Events

[Anjumnagpal]

I have a windows applications.

Form 2 is child form of Form1 . Basically when button on form2 (child form) is clicked, it raise an events, which writes something in testbox on form1 (parent form). This is my code

parent form form1 code:

Public Class Form1
Public mycount As Integer

Private WithEvents obj As New Form2
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

Dim newdoc As Form2
mycount = mycount + 1

newdoc = New Form2()
newdoc.Text = "Doc" + Str(mycount)

newdoc.MdiParent = Me.Parent
newdoc.Show()

End Sub

Private Sub obj_textfill(ByVal txt As String) Handles obj.textfill
TextBox1.Text = txt

End Sub
End Class

form2 child form code:

Public Class Form2
Public Event textfill(ByVal txt As String)

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
RaiseEvent textfill("hi")

End Sub
End Class



This is the first time I am tring to use events.. I am not sure what's going wrong.. the textfill event is never called from form1. Please help

 

[newguy]

In the form1_Load Event:

Addhandler form2.FillText, AddressOf FillText

Then Make a Sub named FillText

Private Sub FillText(ByVal txt As String)
  If Not txt Is Nothing Then
     Textbox1.Text = txt
  End If
End Sub

So when you raise the event and pass the string thru it - will be handled in form1 with this sub. So delete 'WithEvent obj As Form2 ' and your obj.filltext event.

 

[Anjumnagpal]

Tried the above code, still doesnt work:

Here's the code again after the changes:

form2 (child form):

Public Class Form2
Public Event textfill(ByVal txt As String)

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

RaiseEvent textfill("hi")
End Sub
End Class

and form1 (parent form):

Public Class Form1
Public mycount As Integer

'Private WithEvents obj As New Form2
Public Sub form_load()
AddHandler Form2.textfill, AddressOf Textfill
End Sub


Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

Dim newdoc As Form2
mycount = mycount + 1

newdoc = New Form2()
newdoc.Text = "Doc" + Str(mycount)

newdoc.MdiParent = Me.Parent
newdoc.Show()

End Sub

Private Sub Textfill(ByVal txt As String)
If Not txt Is Nothing Then
TextBox1.Text = txt
End If
End Sub

End Class

please look at the code and tell me where is it doing wrong??

 

[newguy]

Your load sub should look like :

Private Sub Form1_Load(byval sender as object, byval e as system.eventargs) Handles Mybase.Load

 

[Anjumnagpal]

Thanks.. Still the sub textfill is not being called..

Here's the corrected code:

Form 2 (child form)

Public Class Form2
Public Event textfill(ByVal txt As String)

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
RaiseEvent textfill("hi")
End Sub
End Class


Form 1 (Parent Form)

Public Class Form1
Public mycount As Integer

Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles MyBase.Load
AddHandler Form2.textfill, AddressOf Textfill
End Sub


Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

Dim newdoc As Form2
mycount = mycount + 1

newdoc = New Form2()
newdoc.Text = "Doc" + Str(mycount)

newdoc.MdiParent = Me.Parent
newdoc.Show()

End Sub

Private Sub Textfill(ByVal txt As String)
If Not txt Is Nothing Then
TextBox1.Text = txt
End If
End Sub

End Class

 

[newguy]

Sorry since you form instance is newform it will have to add the handler...

WithEvents newForm as New Form2
'load event
Addhandler newForm.filltext, AddressOf filltext

 

[Anjumnagpal]

not working again .. here's the code again
form 2 child code:

Public Class Form2
Public Event textfill(ByVal txt As String)

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
RaiseEvent textfill("hi")
End Sub

End Class

form 1 parent class:

Public Class Form1
Public mycount As Integer

WithEvents newForm As New Form2
Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles MyBase.Load
AddHandler newForm.textfill, AddressOf Textfill
End Sub


Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

Dim newdoc As Form2
mycount = mycount + 1

newdoc = New Form2()
newdoc.Text = "Doc" + Str(mycount)

newdoc.MdiParent = Me.Parent
newdoc.Show()

End Sub

Private Sub Textfill(ByVal txt As String)

If Not txt Is Nothing Then
Me.TextBox1.Text = txt
End If
End Sub

End Class

 

[newguy]

You have two objects as New form2, make them the same! newForm or newDoc which one you want, then you should be good...

 

[Anjumnagpal]

Hey-
It worked!!! THANK YOU so much... Thanks for step by step suggestions. I dont why it never was struck me . Thanks again

 

[newguy]

No problem, when in doubt, check all lines, and 1 line of code out of place will screw up the works. Enjoy...

 

[Haxaro]

Why dont you just do this

 Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Form1.TextBox1.Text = "Hello"
End Sub

Just a much simpler way of getting the same answer...

I think thats what you ment anyway

 

[newguy]

Because he wants to learn how to create events and call them in diff forms.

 

[cjard]

Hey-
It worked!!! THANK YOU so much... Thanks for step by step suggestions. I dont why it never was struck me . Thanks again

Small request.

Read this: Visual Basic .NET Forums - BB Code List

And in future, use CODE tags to post code. Also please name your forms/buttons something more meaningful than Form1, Form2, Button1 etc