Get Checked CheckBoxes from a StackPanel in Windows Phone 8.1

I'm trying to get the selected Checkboxes from a Button trigger and it's giving me only null values. What am I doing wrong and how to fix this? This is in Windows Phone 8.1

<ScrollViewer Margin="10,181,10,78">
            <StackPanel x:Name="boxesPanel">
                <CheckBox Content="Colombo"/>
                <CheckBox Content="Galle" />
                <CheckBox Content="Kandy" />
                <CheckBox Content="Polonnaruwa" />
                <CheckBox Content="Sigiriya" />
                <CheckBox Content="Anuradhapura" />
                <CheckBox Content="Jaffna" />
                <CheckBox Content="Haputale" />
                <CheckBox Content="Pottuvil" />
                <CheckBox Content="Bentota" />
                <CheckBox Content="Katharagama" />
                <CheckBox Content="Nuwara Eliya" />
            </StackPanel>
        </ScrollViewer>

private void nextButton_Click(object sender, RoutedEventArgs e)
        {
            List<String> locations = new List<String>();
            for (int x = 0; x < boxesPanel.Children.Count; x++)
            {
                CheckBox temp = (CheckBox) boxesPanel.Children.ElementAt(x);
                if ((bool)temp.IsChecked)
                {
                    //locations.Add(temp.Name);
                    Debug.WriteLine(temp.Name);
                }

            }
            trip.Locations = locations;
            Frame.Navigate(typeof(Duration), trip);
        }

Why is the null values coming? How to get the Names from the check boxes? Thanks in advance! :)