c# - 触发 SelectedIndexChanged 后列表框在视觉上卡住

Question

我有一个结构如下的表单应用程序:

+--------------------------------------------------------------+
|      FormMain                                                |
|+------------------------+-----------------------------------+|
||  Panel ObjectCreation  |         Panel ObjectShow          ||
|+------------------------+-----------------------------------+|
|| Button AddObject()     | listPhones[selectedItem].Id       ||
|| ListBox listBoxPhones  |                                   ||
|+------------------------+-----------------------------------+|
+--------------------------------------------------------------+

两个面板都显示两个单独的窗体，FormObjectCreation 和 FormObjectShow。一旦 ListBox 触发 SelectedIndexChanged 事件，Panel ObjectShow 就会更新。

但是，此后列表框不再在视觉上更新。它仍然有效，仍然触发事件。 The listbox just seems to be frozen visually.

这是按钮调用的 AddObject() 函数:

private void buttonAddObject_Click(object sender, EventArgs e)
{
    PhoneList.Add(new Phone(PhoneList.Count + 1));

    buttonSentTokensToPhone.Visible = true;
    listBoxPhones.DataSource = null;
    listBoxPhones.DataSource = PhoneList;
}

这里是处理引发事件的函数

private void listBoxPhones_SelectedIndexChanged(object sender, EventArgs e)
{
    this.FormMain.ShowCurrentPhone(PhoneList[listBoxPhones.SelectedIndex]);
}

// In FormMain.cs:
public void ShowCurrentPhone(Phone phone)
{
    panelPhone.Controls.Clear();
    FramePhone = new FrmPhone(this, phone) { Dock = DockStyle.Fill, TopLevel = false, TopMost = true };
    FramePhone.Name = "Phone " + phone.Id;
    FramePhone.FormBorderStyle = FormBorderStyle.None;
    panelPhone.Controls.Add(FramePhone);
    panelPhone.BorderStyle = BorderStyle.FixedSingle;
    FramePhone.Show();
}

我试过调试它，但是我没有发现任何异常。我在 .NET 4.7.2 上。有没有人也遇到过这个问题？

更新:正在关注Jimis在下面的评论中，我将 PhoneList 从常规列表更改为 BindingList。代码片段现在看起来像这样:

private BindingList<Phone> PhoneList { get; set; }

private void buttonAddPhone_Click(object sender, EventArgs e)
{
        PhoneList.Add(new Phone(PhoneList.Count + 1));
        buttonSentTokensToPhone.Visible = true;
}

ListBox 现在可以正常工作了。

Answer 1

我用一个表单和一个用户控件(不是表单)做了这个并且它有效:

 public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        public List<Phone> PhoneList { get; private set; }

        private void button1_Click(object sender, EventArgs e)
        {
            PhoneList = new List<Phone>();

            PhoneList.Add(new Phone(PhoneList.Count + 1));

           
            listBox1.DataSource = null;
            listBox1.DataSource = PhoneList;
            listBox1.DisplayMember = "Id";
        }

        private void listBox1_SelectedIndexChanged(object sender, EventArgs e)
        {
            if (listBox1!=null && listBox1.SelectedIndex>=0)
                ShowCurrentPhone(PhoneList[listBox1.SelectedIndex]);
        }
        public void ShowCurrentPhone(Phone phone)
        {
            panel2.Controls.Clear();
            UserControl1 FramePhone = new UserControl1(phone.Id);
            FramePhone.Name = "Phone " + phone.Id;
            panel2.Controls.Add(FramePhone);
            panel2.BorderStyle = BorderStyle.FixedSingle;
        }
    }

public class Phone
    {
        private int id;
        public string PonheNumber;

        public int Id { get => id; set => id = value; }

        public Phone(int id)
        {
            this.id = id;
            this.PonheNumber = "1111";
        }
    }
   

     public partial class UserControl1 : UserControl
    {
        private int id;
        public UserControl1(int id)
        {
            InitializeComponent();
            this.Id = id;
            label1.Text = Id.ToString();
        }

        public int Id { get => id; set => id = value; }
    }