如何更改 ObjectListView 行背景色？

Question

I have an objectlistview from BrightIdeasSoftware. Currently I can add and remove to this list however I can't paint my row colors(NOT HEADER) Simply I want to re color half of my list to red and rest to blue as example.

Normally I would do this :

            for (int i = 0; i < index; i++)
            {
                mainForm.MyListView.Items[i].BackColor = Color.LightGray;
            }
            mainForm.MyListView.Items[index].BackColor = Color.DarkGreen;
            for (int i = index; i < mainForm.MyListView.Items.Count; i++)
            {
                mainForm.MyListView.Items[i].BackColor = Color.FromArgb(18, 18, 18);
            }

But this is not working, I have also tried refreshing object after re color them but still not working. I have checked this but I don't want to do it with a condition I just want to give an index and then re color my listview.

Can someone show me how can I achieve this? Thanks a lot

EDIT : I will share my whole method so it will be clearer..

public void PaintToIndex(int index)
        {
            for (int i = 0; i < index; i++)
            {
                mainForm.MyListView.Items[i].BackColor = Color.LightGray;
            }
            mainForm.MyListView.Items[index].BackColor = Color.DarkGreen;
            for (int i = index; i < mainForm.MyListView.Items.Count; i++)
            {
                mainForm.MyListView.Items[i].BackColor = Color.FromArgb(18, 18, 18);
            }

        }

EDIT2: I think I might found something, I have change my method to this but it's updating itself back.

            for (int i = 0; i < index; i++)
            {
                OLVListItem CurItem = mainForm.MyListView.GetItem(i);
                CurItem.BackColor = Color.LightGray;
                //mainForm.MyListView.RefreshItem(CurItem);
            }
            mainForm.MyListView.GetItem(index).BackColor = Color.LightGray;
            for (int i = index; i < mainForm.MyListView.Items.Count; i++)
            {
                OLVListItem CurItem = mainForm.MyListView.GetItem(i);
                CurItem.BackColor = Color.FromArgb(18, 18, 18);
                //mainForm.MyListView.RefreshItem(CurItem);
            }

When I open RefreshItem it update my OLVListItem back to previous color..

EDIT 3: I found the solution. I did Refresh() after set all my colors but now I have another problem, when I hover with my mouse the color is changing back..

Answer 1

The documentation on their site includes a very similar example . You listen for FormatRow or FormatCell event.

To show customers in red when they owe money, you would set up a handler for the FormatRow event in the IDE, and then do something like this:

private void olv1_FormatRow(object sender, FormatRowEventArgs e) {
    Customer customer = (Customer)e.Model;
    if (customer.Credit < 0)
        e.Item.BackColor = Color.Red;
}

To change the formatting of an individual cell, you need to set UseCellFormatEvents to true and then listen for FormatCell events. To show just the credit balance in red, you could do something like this:

private void olv1_FormatCell(object sender, FormatCellEventArgs e) {
    if (e.ColumnIndex == this.creditBalanceColumn.Index) {
        Customer customer = (Customer)e.Model;
        if (customer.Credit < 0)
            e.SubItem.ForeColor = Color.Red;
    }
}

These events play well with UseAlternatingBackColors. Any formatting you do in these events takes precedence over the alternate back colours.

These events know where the row is going to appear in the control, so the DisplayIndex property of the event can be used for more sophisticated alternate background colour schemes. The DisplayIndex is correct even when the list is showing groups and when the listview is virtual.

To improve performance, FormatCell events are only fired when a handler of the FormatRow event sets UseCellFormatEvents to true. If you want to have a FormatCell event fired for every cell, you can set UseCellFormatEvents on the ObjectListView itself.

Answer 2

Okay I found the solution. This is how I did it

            int CurrentIndex = StaticVariables.MyListView.GetPlaylistCurrentIndex();
            int count = StaticVariables.MyListView.GetPlaylistCount();
            for (int i = 0; i < CurrentIndex; i++)
            {
                OLVListItem item = mainForm.MyListView.GetItem(i);
                item.BackColor = Color.FromArgb(35, 35, 35);
            }
            for (int i = CurrentIndex; i < count; i++)
            {
                OLVListItem item = mainForm.MyListView.GetItem(i);
                item.BackColor = Color.FromArgb(18, 18, 18);
            }
            OLVListItem item2 = mainForm.MyListView.GetItem(CurrentIndex);
            item2.BackColor = Color.DarkGreen;
            mainForm.MyListView.Refresh();

I call this method on FormatRow event. There is 1 more thing I want to mention. This was not working until I checked UseHotControls to false. You know this property do some fancy things when you hover your mouse over the cell or row or whatever but I guess it's not working well with back color changes because when it was true(as default) my ObjectListView was not updating it's back color until I move my mouse over OLV or click any item but then when I was hovering and activating HotControl they were changing their color back to original(Transparent). I manage to change HotControl back color but then still I had the issue with not updating itself. After I set UseHotControls to false and call same method everything work perfectly. I'll leave this method and this long paragraph here in case if someone else is going to need it.