Need a suggestion on a control

[Pickle]

I have a monitoring program that needs to display serial data (messages) in a list. Im not sure on the best form control to use.

Each message has different parts that I want to break up into multiple columns.

So the number of columns will be fixed, the rows could be on the order of 1000's. The rows need to be added on a realtime basis, but no faster than a rate of 3 ms. Not all data has to be seen, so a vertical scroll bar is needed.

 

Some controls Ive some across are flexgrid, or the .net datagrid (heard it was slow though). Right now im leaning on the flexgrid.

 

Any other ideas?

[Nate Bross]

If you use

 

DataGrid.DataSoruce = MyArrayList/StronglyTypedCollection

 

the .NET Datagrid will not be slow; looping through each column and adding them manually

 

for x as integer = 0 to 100
  dg.columns("First").Add(x)
  dg.columns("Last").Add(x)
  dg.columns("custID").Add(x)
  dg.columns("phone").Add(x)
next x

 

it will be very slow.

 

The way I would do it is make a class or structure for the messages and populate an arraylist (good) or a strongly typed collection (better) and set the dg.datasoruce = to it.

 

Like this

 

Public Class Message
   Public Number as Integer
   Public Title as String
   Public Description as String
'you would want to do this better and use properties, etc
End Class

 

Then you would do something like this inside the loop you have to gather the message data

 

Dim AL as ArrayList

Do While...
   Dim myMessage as Message
   myMessage.Number = A number from your source
   myMessage.Title = Title from your source
   'etc with the other properties
   al.Items.Add(myMessage)
Loop

 

and then everytime you want to update the Datagrid do this

 

MyDataGrid.DataSource = Nothing
MyDataGrid.DataSource = AL

 

Hope This Helps

[Pickle]

Great, i already have the class object with properties for the messages, although I did a list( of T) to group them? Will it make a difference using a arraylist instead?

[Pickle]

Never mind, I did it with the array list and it looks good, the data is being populated.

 

What would be different with a strongly typed collection? I have not used one before.

 

Also is there any way to improve the refresh? Right now it has a flash from the entire control being redrawn. Is there a way to only draw the newest items?

Edited March 2, 2006 by Pickle

[rfazendeiro]

What would be different with a strongly typed collection? I have not used one before.

here's a link that talks a little of strongly typed collections

link

 

Also is there any way to improve the refresh? Right now it has a flash from the entire control being redrawn. Is there a way to only draw the newest items?

well i'm no expert but have you tried beginupdate and EndUpdate methods?

[Pickle]

There are no beginupdate/endupdate methods for this control

[Nate Bross]

I am not sure; possible these work in the same or similar way?

 

       DataGridView1.BeginEdit() 'Requires True/False Param
       DataGridView1.EndEdit()

[Pickle]

Those appear to only apply to one row object

 

Im refreshing the gridview like you said with

MyDataGrid.DataSource = Nothing
MyDataGrid.DataSource = AL 

   Sub Record_Class2Message(ByVal strDir As String, ByVal intData() As Integer)
       Dim Received_Message As New Class2_Message
       Dim totalbytes As Integer = intData(0) And &HF

       Received_Message.Type = strDir
       Received_Message.Header = Hex(intData(1)).PadLeft(2, "0"c) & " " & _
                                 Hex(intData(2)).PadLeft(2, "0"c) & " " & _
                                 Hex(intData(3)).PadLeft(2, "0"c)
       For index As Integer = 4 To totalbytes - 1
           Received_Message.Data &= Hex(intData(index)).PadLeft(2, "0"c) & " "
       Next
       Received_Message.Timestamp = Str((intData(totalbytes + 1) << 8) + intData(totalbytes + 2))

       Class2_Messages.Add(Received_Message)

       SetDataGridSource(Nothing) 'needed for mulithread
       SetDataGridSource(Class2_Messages) 'needed for mulithread
   End Sub

   ' This delegate enables asynchronous calls for setting
   ' the text property on a TextBox control.
   Delegate Sub SetDataGridSource_Callback(ByVal [data] As ArrayList)

   ' This method demonstrates a pattern for making thread-safe
   ' calls on a Windows Forms control. 
   '
   ' If the calling thread is different from the thread that
   ' created the TextBox control, this method creates a
   ' SetTextCallback and calls itself asynchronously using the
   ' Invoke method.
   '
   ' If the calling thread is the same as the thread that created
   ' the TextBox control, the Text property is set directly. 

   Private Sub SetDataGridSource(ByVal [data] As ArrayList)

       ' InvokeRequired required compares the thread ID of the
       ' calling thread to the thread ID of the creating thread.
       ' If these threads are different, it returns true.
       If Me.Class2DataGrid.InvokeRequired Then
           Dim d As New SetDataGridSource_Callback(AddressOf SetDataGridSource)
           Me.Invoke(d, New Object() {[data]})
       Else
           Me.Class2DataGrid.DataSource = [data]
           If Not [data] Is Nothing Then
               If Not [data].Count = 0 Then
                   Me.Class2DataGrid.CurrentRowIndex = [data].Count - 1
               End If
           End If
       End If
   End Sub

Edited March 2, 2006 by Pickle

[Pickle]

I just have to say that the data grid is totally useless as a control for adding data at a realtime speed. The redraw is too slow, I will probally have to use a listview and format the lines to appear to have columns.

[Cags]

What do you mean by 'format the lines to appear to have columns'? The ListView control supports columns.

[mskeel]

Yes, cags is correct. You have to change the view property of the listview to details. You can also add columns from the designer if you wanted (but they will only be visible if the view is details or tile.

[Pickle]

Yes' date=' cags is correct. You have to change the view property of the listview to details. You can also add columns from the designer if you wanted (but they will only be visible if the view is details or tile.

 

Actually I meant Listbox, but maybe you gave me a new solution. I will try it.

Is there a similar way to assign data like the gridview.datasource?

Edited March 7, 2006 by Pickle

[Cags]

The ListView control has a DataSource property the same as the DataGrid I believe.

[Pickle]

The ListView control has a DataSource property the same as the DataGrid I believe.

 

hmmm, I didnt see it in MSDN. I have seen a example using add range with a array of listviewitems.

[Cags]

Your correct, I was thinking of a ListBox. As you say it can be done using the AddRange() method.