Need some list view help.. Please :) -> Resolved

[RudyL]

I am using a list view with several columns in it. I need to be able to sort all the rows based on a user selected column.. Exactly like in Windows Explorer where if you click on "Name" it sorts by name, click on it again and it sorts in the other direction, and the same for all other columns..

[RudyL]

To add some more detail.. I have this example from M$, but it does not work..

http://msdn.microsoft.com/library/de...ortertopic.asp


I tried to berak pont in the sub that handlesthe column click event but it gives me a message that the breakpoint will never be hit..

[RobDog888]

To get your breakpoint to be hit you need to run the project by pressing F5 or Debug > Run. If your
pressing the exclamation point toolbar button or menu item it will bypass breakpoints.

[RudyL]

To get your breakpoint to be hit you need to run the project by pressing F5 or Debug > Run. If your
pressing the exclamation point toolbar button or menu item it will bypass breakpoints.

ahh... Not it, but you got me to see why.. I hat it set to Release still.. oopss.. However, It is still not working right.. It will sort the first time I click on it, but if I click again in the same column it will not sort the other way (asc/desc)..

[zaza]

Hello,

Have you gone through and checked all the little bits, like you've definitely included the class ListViewItemComparer at the bottom, and the Imports System.Collections at the top?

The M$ example works fine for me.

zaza

[RudyL]

Hello,

Have you gone through and checked all the little bits, like you've definitely included the class ListViewItemComparer at the bottom, and the Imports System.Collections at the top?

The M$ example works fine for me.

zaza

I think so.

This is in the form..

Imports System
Imports System.Windows.Forms
Imports System.Drawing
Imports System.Collections
 
.......
 
    Private Sub lvTestYields_ColumnClick(ByVal sender As Object, ByVal e As System.Windows.Forms.ColumnClickEventArgs) Handles lvTestYields.ColumnClick
 
        ' Set the ListViewItemSorter property to a new ListViewItemComparer 
        ' object. Setting this property immediately sorts the 
        ' ListView using the ListViewItemComparer object.
        Me.lvTestYields.ListViewItemSorter = New ListViewItemComparer(e.Column)
 
    End Sub

and I created a class with this in it..

Class ListViewItemComparer
    ' Implements the manual sorting of items by columns.
 
    Implements IComparer
 
    Private col As Integer
 
    Public Sub New()
 
        col = 0
 
    End Sub
    Public Sub New(ByVal column As Integer)
 
        col = column
 
    End Sub
    Public Function Compare(ByVal x As Object, ByVal y As Object) As Integer Implements IComparer.Compare
 
        Return [String].Compare(CType(x, ListViewItem).SubItems(col).Text, CType(y, ListViewItem).SubItems(col).Text)
 
    End Function
End Class

The class stuff wouldn't get put in the form would it?

[zaza]

Hi,

In the columnclick event, after Me.blahblah = New blahblah, put:

lvtestyields.sort()

See if that works.

Fingers Xd

zaza

[RudyL]

Hi,

In the columnclick event, after Me.blahblah = New blahblah, put:

lvtestyields.sort()

See if that works.

Fingers Xd

zaza

Nope.. I just noticed another wierd thing.. I have 5 columns.. If I click on column 0 it sorts by column 0 asc.. If I click on column 1 it sorts by column 0 desc.. The same for columns 2 and 3, but they sort based on column 2..

[zaza]

Hello,

Actually, having gone back to my sorter, it only sorts ascending. I'm sure I had it working before...
Anyway, try selecting some more data to put into your listview - I think it may just be coincidence that it appears to sort like that. I found a similar "phenomenon" until I changed what was going into the listview. The upshot of what I have found with regard to mine is that it more or less sorts in ascending order. Whichever column is clicked, it will sort mostly alphabetically according to that. By "mostly", I mean that the sorting occurs based only on what is in that column (although in the case of multiple items which are teh same, it sorts on the previous column), but it seems to have slightly odd way of choosing what comes first in the order. Square brackets come above curlies, which come above alphanumeric. I don't know why that is, because it doesn't reflect their ascii codes. In all other respects, though, it seems to sort in ascending order by ascii code based firstly on the column that you choose, then on the preceding column.

Thanks for making me look at my code again. As I say, I thought I'd sorted this out (hohoho). Now I'll have to look at it again.

Cheers

zaza

EDIT:
Ah yes, that's what I did. Create a second comparer class, the same as the first but swap the x and y in the "Return [string]" line. Then, use a flag (such as a public variable called "sortorder") to determine one of two courses of action in your columnclick event. If "sortorder" is 1, then use listviewitemcomparer1 and set "sortorder = -1". If "sortorder = -1", then use listviewitemcomparer2 and set "sortorder = 1". This swaps between the two versions of the sort, enabling you to sort ascending or descending each time you click.

HTH

zaza

[kleinma]

you add a new class to your project and you paste in that code.

You then compile your application, and the new ListViewEx should be in your toolbox so you can just drag it to your form.

[d2005]

Thank you kleinma..


Wouldnt know how to force that to a certain column.. on like the load... ??

I tried raising an colum click but that just ran into my listview column click event - (no code in it) and never hit the class.

Basically on my list view column 2 is like a date field and and i want to sort this as soon as default

[kleinma]

Basically on my list view column 2 is like a date field and and i want to sort this as soon as default

Where does the data come from? Likely it is in some sort of array or collection or database table already right? So sort it by date when you load the data, then load the listview with the already sorted data.