private void BtnEdit_Click(object sender, EventArgs e)
{
Activity_DAO activity_dao = new Activity_DAO();
int activityUpId = 0;
for (int i = 0; i < activityListView.Items.Count; i++)
{
if (activityListView.Items[i].Checked)
{
activityUpId = int.Parse(activityListView.Items[i].Text);
}
}
activity_dao.updateActivityById(activityUpId, tboxName.Text, dateTimePickerStart.Value, dateTimePickerEnd.Value);
refreshActivities();
}