Hi.
I'm currently evaluating the UniToolbox 2, and I think there is a memory leak.
1. Load Form2 by using another (Form1).
2. In the load-event of Form2 load 200 UniTextBoxes.
3. Then unload Form2 and therefore the 200 UniTextboxes.
4. After about 5 Minutes periodical load and unload (using a Timer in Form1) memory durable increases.

Equal if you separately unload the UniTextboxes in the unload-event or queryunload-event.

Mike

Sorry for the delay in replying Mike, we're looking into the issue. Can I ask how much memory you see leaking?

Hi Nico,

i've tested it for 12 passes. Here the list of the memory allocation:
7512; 7544; 7656; 7636; 7668; 7656; 7700; 7716; 7764; 7756; 7764; 7776 (KB)

GDI objects seems ok.

Mike


Enclosed then code, its not very tricky ;-)
Form1 -----------------------------

Option Explicit
Dim blnStop As Boolean

Private Sub Command1_Click()
'Timer1.Interval = 200
'Timer1.Enabled = True
Form2.Show
End Sub

Private Sub Command2_Click()
blnStop = True
End Sub

Private Sub Timer1_Timer()
Static lngLoop As Long
If Not CBool(lngLoop Mod 5) Then
Form2.Show
End If
End Sub

Form2 ----------------------------------------
Option Explicit

Private Sub Form_Load()
Timer1.Interval = 1000
Timer1.Enabled = True
End Sub

Private Sub Form_QueryUnload(Cancel As Integer, UnloadMode As Integer)
Dim lngi As Long
For lngi = 201 To 2 Step -1
Unload UniText2(lngi - 1)
Next lngi
DoEvents
End Sub

Private Sub Timer1_Timer()
Dim lngi As Long
Dim lngK As Long

For lngi = 1 To 200
Load UniText2(lngi)
UniText2(UniText2.Count - 1).Visible = True
UniText2(UniText2.Count - 1).Top = UniText2(UniText2.Count - 1).Top + (lngK)
UniText2(UniText2.Count - 1).BackColor = RGB(Rnd(1) * 255, Rnd(1) * 255, Rnd(1) * 255)
DoEvents
lngK = lngK + 50
Next lngi

Unload Me
End Sub

Hi Nico,

is there a solution for my problem?

Mike

Mike,

We've been looking at the issue and it does appear that there are some memory issues with a large number of controls created in this way. Unfortunately we don't have a simple solution for you at this time other than to just grin and bear it, or to create the controls using the standard method.

Hi Nico,

thanks or reply.
Ouh, you think this is a large number of controls, there are only 200 controls.
We are working on a 24/7 application. Ok, the application is ready for a long time but now we have to translate it in russian.
So, in a industrially used 24/7 application grin and bear is not the right attitude.

What is the standard method to create controls when do not know the number?

Mike

Please see James's response below, he has a better handle on the situation.

I do not believe that the data you have collected implies a memory leak. If fact, because at times the memory usage actually decreases I would be confident in saying there is not a memory leak. Memory either leaks or it does not - it does not happen only sometimes when repeatedly performing the same set of actions.

It is far more that the fluctuations in memory allocation you are seeing are simply caused by the VB Runtime's memory management and garbage collection system as it modifies the memory required by the program.

I have run you code for a short while and concluded that the memory usage stabilises quite quickly before continuing to fluctuate within a small range.

By the way, although you think the Form2 is actually being unloaded, it is not being destroyed until the program has terminated (Try 'MsgBox "Form2_Form_Terminate()"' in the Form_Terminate() event). This is because you are using the Form2 without defining a specific instance variable. VB will create its own variable and manage its lifetime according to its own rules.

You also don't really need to unload the control array explicitly; when the form is unloaded, any controls it contains will also be unloaded.

I hope this helps.

Hi,

we practice this for many years.
If we use the standard VB.Textbox it works fine.

if you create a usercontrol, we have already made this too, you have take care of this:
M$: Q190511

Mike