I am self-studying C# and trying to build a windows forms app. I don't know what I'm doing wrong here, but I can't see any data when I click the 'List' button in Form1 to see the submitted data from textbox (Form1)
Details about the app:
- 1 main class and 3 inherited classes
- First form (Form1) has three radio buttons, three text boxes, three control buttons (save, clear, and view second form)
- Second form (Form2) has a ListView that shows the user input from the Form1.
--- Form 1 ---
public partial class Form1 : Form
{
    int pos = 0;
    ElectronicDevice[] ElectronicDevices = new ElectronicDevice [10];
    
    public Form1()
    {
        InitializeComponent();
    }
    private void submit_Click(object sender, EventArgs e)
    {
        if (radioButton1.Checked)
        {
            ElectronicDevices[pos] = new ElectronicDevice(textBox1.Text, textBox2.Text, textBox3.Text);
        }
        if (radioButton2.Checked)
        {
            ElectronicDevices[pos] = new ElectronicDevice(textBox1.Text, textBox2.Text, textBox3.Text);
        }
        if (radioButton3.Checked)
        {
            ElectronicDevices[pos] = new ElectronicDevice(textBox1.Text, textBox2.Text, textBox3.Text);
        }
        pos++;
    }
    private void clear_Click(object sender, EventArgs e)
    {
        textBox1.Clear();
        textBox2.Clear();
        textBox3.Clear();
    }
    private void list_Click(object sender, EventArgs e)
    {
        
        Form2 ViewList = new Form2();
         
        for (int i = 0; i < pos; i++)
        {
            // System.NullReferenceException: 'Object reference not set to an instance of an object.' Local2 was null.
                 ViewList.Controls["txtList"].Text +=
                 ElectronicDevices[i].Type() + "\r\n" +
                 ElectronicDevices[i].Brand + " " +
                 ElectronicDevices[i].Model + " " +
                 ElectronicDevices[i].Year + " ";
        }
        ViewList.ShowDialog();
    }
}
--- Main class ---
class ElectronicDevice
{
    public string Brand;
    public string Model;
    public string Year;
    public ElectronicDevice() {
        Brand = "";
        Model = "";
        Year = "";
    }
    public ElectronicDevice(string iBrand, string iModel, string iYear) 
    {
        Brand = iBrand;
        Model = iModel;
        Year = iYear;
    }
    
    public virtual string Type() { return "Device"; }
}
--- One of the inherited classes ---
class SmartPhone : ElectronicDevice
{
    public SmartPhone() : base()
    {
    }
    public SmartPhone(string iBrand, string iModel, string iYear) : base(iBrand, iModel, iYear)
    {
    }
    public override string Type() { return "SmartPhone"; }
}   
Thanks in advance!
