Hi Jens,

In my search for an elegant way to implement scrolling I came across
your question. It seems like mouse wheel message is not routed to any
kind of control or layout that has the UserControl as base class.
Hovever the mouse wheel messages is routed to controls and layouts
having the Form as base class. Therefore you can get around your
problem by inserting a mouse wheel event handler in your form, on which
your control is placed. Create a mouse handler function in your user
control and call it manually from your form mouse wheel event handler.

Add an event handler in the form-class constructor:
this.MouseWheel += new MouseEventHandler(YourForm_MouseWheel);

Insert an event handler method in the form class:
void YourForm_MouseWheel(object sender, MouseEventArgs e)
{
  this.yourUserControl.ParentForm_MouseWheel(sender, e);
}

Create a method for control the scroll bar in your user control:
public void ParentForm_MouseWheel(object sender, MouseEventArgs e)
{
  int scrollPosition = this.flowLayoutPanel.VerticalScroll.Value;
  int scrollChange = e.Delta * -1;

  scrollPosition += scrollChange;

  if (scrollPosition < this.flowLayoutPanel.VerticalScroll.Minimum)
     scrollPosition = this.flowLayoutPanel.VerticalScroll.Minimum;
  else if (scrollPosition >
this.flowLayoutPanel.VerticalScroll.Maximum)
     scrollPosition = this.flowLayoutPanel.VerticalScroll.Maximum;

  this.flowLayoutPanel.VerticalScroll.Value = scrollPosition;
}

I have a feeling there is a better way of doing it, but haven't found
it yet. However this is how I have implemented for now it and it works

described anywhere.

Best Regards
Steen

jens.ro skrev: