Solved

using MDIcontainer

Posted on 2006-10-31
8
176 Views
Last Modified: 2010-04-23
hellow guys.. i got a form named "form_master" which "IsMdiContainer" = True

the following code is the way how i open another form in "form_master"
my question is: How do i prevent duplicated "form_sales" being open?

----------------------------------------------------------------------------------------------------
Public Class form_master

    Dim sales_form As form_sales

    Private Sub button_1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btn_POS.Click

        sales_form = New form_sales()
        sales_form.MdiParent = Me
        sales_form.Show()

    End Sub

End Class
0
Comment
Question by:kengkit
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 4
  • 4
8 Comments
 
LVL 86

Expert Comment

by:Mike Tomlinson
ID: 17845231
Something like...

Public Class form_master

    Private WithEvents sales_form As New form_sales

    Private Sub button_1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btn_POS.Click
        If sales_form Is Nothing Then
            sales_form = New form_sales()
            sales_form.MdiParent = Me
            sales_form.Show()
        End If
        If sales_form.WindowState = FormWindowState.Minimized Then
            sales_form.WindowState = FormWindowState.Normal
        End If
        sales_form.Activate()
    End Sub

    Private Sub sales_form_FormClosed(ByVal sender As Object, ByVal e As System.Windows.Forms.FormClosedEventArgs) Handles sales_form.FormClosed
        sales_form = Nothing
    End Sub

End Class
0
 

Author Comment

by:kengkit
ID: 17847137
To: Idle_Mind

how come i still can open duplicated form althought i used your code exactly?

The application doen't stop even I put the breakpoint at "If sales_form Is Nothing"
why?? (I was using visual studio .net 2005

Private Sub button_1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btn_POS.Click

        If sales_form Is Nothing Then  (breakpoint)
            sales_form = New form_sales()
            sales_form.MdiParent = Me
            sales_form.Show()
        End If

        If sales_form.WindowState = FormWindowState.Minimized Then
            sales_form.WindowState = FormWindowState.Normal
        End If

        sales_form.Activate()

    End Sub
0
 

Author Comment

by:kengkit
ID: 17847159
I found tat my application doesn't recognize my changed code...

For an instance..

Private Sub Button5_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button5.Click

    MsgBox("Hellow")

End Sub

The message box doesn't pop up when i click button5
0
Instantly Create Instructional Tutorials

Contextual Guidance at the moment of need helps your employees adopt to new software or processes instantly. Boost knowledge retention and employee engagement step-by-step with one easy solution.

 
LVL 86

Expert Comment

by:Mike Tomlinson
ID: 17847566
Try deleting the "bin" subfolder in your project and running it again.
0
 

Author Comment

by:kengkit
ID: 17847579
all right.. now the problem is..

sales_form doesn't pop up.... unless i changed the code

from "If sales_form Is Nothing Then" to "If sales_form Is Nothing = False Then"

----------------------------------------------------------------------------------------------

Public Class form_master

    Private WithEvents sales_form As New form_sales

    Private Sub sales_form_FormClosed(ByVal sender As Object, ByVal e As System.Windows.Forms.FormClosedEventArgs) Handles sales_form.FormClosed
        sales_form = Nothing
    End Sub

    Private Sub ToolStripButton1_Click_1(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ToolStripButton1.Click

        If sales_form Is Nothing = False Then
            sales_form = New form_sales()
            sales_form.MdiParent = Me
            sales_form.Show()
        End If

        If sales_form.WindowState = FormWindowState.Minimized Then
            sales_form.WindowState = FormWindowState.Normal
        End If

        sales_form.Activate()
    End Sub

End Class
0
 
LVL 86

Expert Comment

by:Mike Tomlinson
ID: 17847595
You're using VB.Net 2005 right?

Try:

        If IsNothing(sales_form) Then
            sales_form = New form_sales()
            sales_form.MdiParent = Me
            sales_form.Show()
        End If
0
 

Author Comment

by:kengkit
ID: 17847602
Yup.. i'm using VS.net 2005 (VB)

i tried ur code oledi.. but the problem is existed
0
 
LVL 86

Accepted Solution

by:
Mike Tomlinson earned 20 total points
ID: 17847734
Sorry...

Public Class form_master

    Private WithEvents sales_form As form_sales          '<------- removed the "new"

    Private Sub sales_form_FormClosed(ByVal sender As Object, ByVal e As System.Windows.Forms.FormClosedEventArgs) Handles sales_form.FormClosed
        sales_form = Nothing
    End Sub

    Private Sub ToolStripButton1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ToolStripButton1.Click
        If IsNothing(sales_form) Then
            sales_form = New form_sales()
            sales_form.MdiParent = Me
            sales_form.Show()
        ElseIf sales_form.WindowState = FormWindowState.Minimized Then
            sales_form.WindowState = FormWindowState.Normal
        End If
        sales_form.Activate()
    End Sub

End Class
0

Featured Post

PeopleSoft Has Never Been Easier

PeopleSoft Adoption Made Smooth & Simple!

On-The-Job Training Is made Intuitive & Easy With WalkMe's On-Screen Guidance Tool.  Claim Your Free WalkMe Account Now

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

If you're writing a .NET application to connect to an Access .mdb database and use pre-existing queries that require parameters, you've come to the right place! Let's say the pre-existing query(qryCust) in Access takes a Date as a parameter and l…
The ECB site provides FX rates for major currencies since its inception in 1999 in the form of an XML feed. The files have the following format (reducted for brevity) (CODE) There are three files available HERE (http://www.ecb.europa.eu/stats/exch…
In an interesting question (https://www.experts-exchange.com/questions/29008360/) here at Experts Exchange, a member asked how to split a single image into multiple images. The primary usage for this is to place many photographs on a flatbed scanner…
I've attached the XLSM Excel spreadsheet I used in the video and also text files containing the macros used below. https://filedb.experts-exchange.com/incoming/2017/03_w12/1151775/Permutations.txt https://filedb.experts-exchange.com/incoming/201…

733 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question