Question

I’m working on a project in Lightswitch and I’m trying to handle the keyup event on specific screen

I couldn’t find it, where can I find those events (such us KeyUp KeyDown LostFocus ext. )

and if they are not supported what should I do to handle a situation like that?

Answer 1

I guess you are referring to controls and not the actual screen. So, for example, to handle keyboard events on a textbox, one way of achieving it is like in this example, where I have an “Address1” textbox and I want to change its text whenever the user types a certain letter:
1 – On the Activated event of the screen, you can get to the required textbox:

partial void CustomersListDetail_Activated()
{
    this.FindControl("Address1").ControlAvailable += AddressTextBoxAvailable;
}

2 – On the Available event handler, you can connect with the required event (you can have KeyUp, KeyDown, LostFocus and others):

private void AddressTextBoxAvailable(object sender, ControlAvailableEventArgs e)
{
    ((System.Windows.Controls.TextBox) e.Control).KeyUp += AddressTextBoxKeyUp;
}

3 – On the KeyUp event handler, you can do your manipulation:

private void AddressTextBoxKeyUp(object sender, KeyEventArgs e)
{
    if (e.Key == Key.A)
    {
        ((System.Windows.Controls.TextBox) sender).Text = "You typed A";
    }
}