Basically if you have a standard Listview that has multi-selection turned on, the mouse up and down events work fine.
But if you turn off multi-selection and click and hold your mouse button on the Listview, it immediately fires down and then up event while the mouse button is still down.
Is there a way to prevent this? I only want the mouse up event to trigger when I release the mouse button.
ListView mouse event processing in WndProc is a bit complicated. This is what I could do by overriding OnMouseUp and WndProc to stop raisng the unnecessary MouseUp:
using System.Collections.Specialized;
using System.Reflection;
using System.Windows.Forms;
public class MyListView : ListView
{
const int WM_LBUTTONUP = 0x0202, WM_RBUTTONUP = 0x0205, WM_MBUTTONUP = 0x0208;
const int LISTVIEWSTATE_mouseUpFired = 0x00080000;
FieldInfo listViewStateField;
public MyListView()
{
listViewStateField = (typeof(ListView)).GetField("listViewState",
BindingFlags.NonPublic | BindingFlags.Instance);
}
protected override void WndProc(ref Message m)
{
if (m.Msg == WM_LBUTTONUP || m.Msg == WM_MBUTTONUP || m.Msg == WM_RBUTTONUP) {
var value = (BitVector32)listViewStateField.GetValue(this);
value[LISTVIEWSTATE_mouseUpFired] = true;
listViewStateField.SetValue(this, value);
var x = (m.LParam.ToInt32() & 0xffff);
var y = (m.LParam.ToInt32() >> 16) & 0xffff;
var e = new MouseEventArgs(
m.Msg == WM_LBUTTONUP ? MouseButtons.Left :
m.Msg == WM_MBUTTONUP ? MouseButtons.Middle :
MouseButtons.Right, 1, x, y, 0);
OnMouseUp(e);
}
base.WndProc(ref m);
}
protected override void OnMouseUp(MouseEventArgs e)
{
if (Control.MouseButtons == MouseButtons.None)
base.OnMouseUp(e);
}
}