Work around Ms Access continuous form? - sql

Question

The problem
In the following form i want to accomplish two things
When Post check box is ticked i.e. when post= true a query should run targeting the current record only and subtracting the amount with balance field in the customer table.
UPDATE Customer INNER JOIN [Loan Payment] ON Customer.CUSID = [Loan Payment].CUSID SET Customer.CUSBalance = [Customer]![CUSBalance]-[Forms]![Loan Payment]![Amount]
WHERE (((Customer.CUSID)=[Forms]![Loan Payment]![CUSID]));
BUT INSTEAD THE WHEN THE QUERY IS EXECUTED FOR EXAMPLE ON LP6 INSTEAD OF [BALANCE]-20 IT DOES BALANCE-110 i.e. THE QUERY IS RUNNING ON ALL FIELDS
When the query have ran and post has been changed to true the post check box of the current record should become disabled so that the query may not ran twice or more times
AND I FOUND THAT CONDITIONAL FORMATTING CANNOT BE APPLIED TO TEXT BOXES
Requirement
I would like to know if i can achieve what i want and how?
Any workaround or alternative solution to what i am currently trying to achiee.

Answer 1

Firstly, I was using the wrong SQL.
UPDATE Customer SET Customer.CUSBalance = [Customer]![CUSBalance]-[Forms]![Loan Payment]![Amount]
WHERE (((Customer.CUSID)=[Forms]![Loan Payment]![CUSID]));
Secondly I found that conditional formatting can not be applied to check boxes so I had to find a workaround and I found three.
work around 1
I locked the Post check box and introduced a button which if Post = false would run the query and make Post = True
MY FORM NOW
The Code I used on the post button [on click procedure]
Private Sub Command19_Click()
If Me.Post = False Then
DoCmd.SetWarnings False
DoCmd.OpenQuery "updateCustomerLoan"
DoCmd.SetWarnings True
Me.Post = True
MsgBox ("Record has been Posted")
ElseIf Me.Post = True Then
MsgBox ("Record has already been posted")
End If
End Sub
Work around 2
I applied the following code on post_update() where I wrote two queries one do query (update) and one undo query (update)
Private Sub Post_AfterUpdate()
If Me.Post = True Then
DoCmd.SetWarnings False
DoCmd.OpenQuery "payLoanONpost"
DoCmd.SetWarnings True
MsgBox ("The record has been posted")
ElseIf Me.Post = False Then
DoCmd.SetWarnings False
DoCmd.OpenQuery "unpayLoanONunpost"
DoCmd.SetWarnings True
MsgBox ("Record has been unposted")
End If
End Sub
Work around 3 (by far the best and does what I initially set out to do
Here I only used one update query
Private Sub Post_AfterUpdate()
If Me.Post = True Then
DoCmd.SetWarnings False
DoCmd.OpenQuery "payLoanONpost"
DoCmd.SetWarnings True
MsgBox ("The record has been posted")
ElseIf Me.Post = False Then
MsgBox ("The record cannot unposted")
Me.Post = True
End If
End Sub