Question

When I resize a column, it does not redraw the data with the updated alignment. I’ve tried Invalidating, Refreshing, and a few other things. Nothing has worked. Does anyone know a workaround? I have not tried this in mono for Windows.

To see what I mean, drop this control on a form, and run it in mono for Linux:

using System;
using System.Collections.Generic;
using System.Text;
using System.Windows.Forms;
using System.Drawing;

class MyListView : ListView
{
  private readonly List<ListViewItem> items_ = new List<ListViewItem>();
  public MyListView()
  {
    VirtualMode = true;
    Columns.Add("Col 1");
    Columns.Add("Col 2");
    Columns.Add("Col 3");
    Add(new ListViewItem(new[] { "a", "b", "c" }));
    Add(new ListViewItem(new[] { "a", "b", "c" }));
    Add(new ListViewItem(new[] { "a", "b", "c" }));
    Add(new ListViewItem(new[] { "a", "b", "c" }));
    Add(new ListViewItem(new[] { "a", "b", "c" }));
  }
  protected override void OnRetrieveVirtualItem(RetrieveVirtualItemEventArgs e)
  {
    e.Item = items_[e.ItemIndex];
    base.OnRetrieveVirtualItem(e);
  }
  public void Add(ListViewItem item)
  {
    items_.Add(item);
    VirtualListSize = items_.Count;
  }
  protected override void OnDrawColumnHeader(DrawListViewColumnHeaderEventArgs e)
  {
    e.DrawText();
    base.OnDrawColumnHeader(e);
  }
  protected override void OnDrawSubItem(DrawListViewSubItemEventArgs e)
  {
    var text = ((ListViewItem.ListViewSubItem)e.SubItem).Text;
    using (var brush = new SolidBrush(e.SubItem.ForeColor))
    {
      e.Graphics.DrawString(text, Font, brush, e.Bounds);
    }
    base.OnDrawSubItem(e);
  }
  protected override void OnColumnWidthChanged(ColumnWidthChangedEventArgs e)
  {
    base.OnColumnWidthChanged(e);
    Invalidate(true); // Nope, that didn't work
    Refresh(); // Nope, that didn't work
  }
}

Answer 1

I figured it out. While my method of storing and reusing the ListViewItem instances works fine in Windows, mono prefers that I recreate them in the body of OnRetrieveVirtualItem.