Question

我有以下代码，我想弄清楚，但我完全难过。我将进度条添加到列表视图中，但我真的不知道如何访问每个进度条以更新进度值。

public ProgressBar LvAddProgB(ListView LV, int LVII, int LVColI, string lvName)
{
    Rectangle SizeR = default(Rectangle);
    ProgressBar ProgBar = new ProgressBar();

    SizeR = LV.Items[LVII].Bounds;
    SizeR.Width = LV.Columns[LVColI].Width;
    if (LVColI > 0)
    {
        SizeR.X = SizeR.X + LV.Columns[LVColI - 1].Width;
    }
    ProgBar.Parent = LV;
    ProgBar.Name = lvName;
    ProgBar.SetBounds(SizeR.X, SizeR.Y, SizeR.Width, SizeR.Height);
    ProgBar.Visible = true;
    ProgBar.Maximum = 1000;
    ProgBar.Step = 1;

    return ProgBar;
}

private void button1_Click(object sender, EventArgs e)
{
    for (int x = 0; x < 3; ++x)
    {
        ListViewItem item = new ListViewItem();
        item.Text = "d.Name";
        item.SubItems.Add("                 ");
        listView1.Items.Add(item);
        LvAddProgB(listView1, x, 1, "Lview" + x.ToString());
    }
}

Answer 1

如果您使用某种键，可以将它从Controls集合中取出来进行更新。由于每个都显示为它是ListView的一部分，因此两者之间似乎存在某种联系。密钥还将提供链接项目和相关ProgressBar。

的方法

假设您的ListView是Details视图，只需在最后添加一个子项，不带相关的ColumnHeader。数据不会显示，但仍与项目相关。使用与ProgressBar名称相同的文字，很容易找到。

我的ListView有3列：{Item, Name, Completion}，但代码会添加第4个子项来存储密钥：

private void AddLVItem(string key, string name, int value)
{ 
    ListViewItem lvi = new ListViewItem();
    ProgressBar pb = new ProgressBar();

    lvi.SubItems[0].Text = name;
    lvi.SubItems.Add(value.ToString());
    lvi.SubItems.Add("");
    lvi.SubItems.Add(key);            // LV has 3 cols; this wont show
    lv.Items.Add(lvi);

    Rectangle r = lvi.SubItems[2].Bounds;
    pb.SetBounds(r.X, r.Y, r.Width, r.Height);
    pb.Minimum = 1;
    pb.Maximum = 10;
    pb.Value = value;
    pb.Name = key;                   // use the key as the name
    lv.Controls.Add(pb);
}

然后，更新给定键的值和进度条的方法：

private void UpdateItemValue(string key, int value)
{ 
    ListViewItem lvi;
    ProgressBar pb;

    // find the LVI based on the "key" in 
    lvi = lv.Items.Cast<ListViewItem>().FirstOrDefault(q => q.SubItems[3].Text == key);
    if (lvi != null)
        lvi.SubItems[1].Text = value.ToString();

    pb = lv.Controls.OfType<ProgressBar>().FirstOrDefault(q => q.Name == key);
    if (pb != null)
        pb.Value = value;
}

用法：

// add some data
AddLVItem("A", "Ziggy", 1);
AddLVItem("B", "Zacky", 1);
AddLVItem("C", "Zoey", 1);
AddLVItem("D", "Zeke", 1);

// update the displayed value and progressbar using the key:
UpdateItemValue("A", 6);
UpdateItemValue("B", 5);
UpdateItemValue("C", 8);
UpdateItemValue("D", 2);

Answer 2

    #region Windows Form Designer generated code

    /// <summary>
    /// Required method for Designer support - do not modify
    /// the contents of this method with the code editor.
    /// </summary>
    private void InitializeComponent()
    {
        this.button1 = new System.Windows.Forms.Button();
        this.listView1 = new System.Windows.Forms.ListView();
        this.columnHeader1 = ((System.Windows.Forms.ColumnHeader)(new System.Windows.Forms.ColumnHeader()));
        this.columnHeader2 = ((System.Windows.Forms.ColumnHeader)(new System.Windows.Forms.ColumnHeader()));
        this.columnHeader3 = ((System.Windows.Forms.ColumnHeader)(new System.Windows.Forms.ColumnHeader()));
        this.SuspendLayout();
        // 
        // button1
        // 
        this.button1.Location = new System.Drawing.Point(12, 12);
        this.button1.Name = "button1";
        this.button1.Size = new System.Drawing.Size(75, 23);
        this.button1.TabIndex = 0;
        this.button1.Text = "button1";
        this.button1.UseVisualStyleBackColor = true;
        this.button1.Click += new System.EventHandler(this.button1_Click);
        // 
        // listView1
        // 
        this.listView1.Columns.AddRange(new System.Windows.Forms.ColumnHeader[] {
        this.columnHeader1,
        this.columnHeader2,
        this.columnHeader3});
        this.listView1.GridLines = true;
        this.listView1.Location = new System.Drawing.Point(12, 64);
        this.listView1.Name = "listView1";
        this.listView1.Size = new System.Drawing.Size(504, 164);
        this.listView1.TabIndex = 1;
        this.listView1.UseCompatibleStateImageBehavior = false;
        this.listView1.View = System.Windows.Forms.View.Details;
        // 
        // columnHeader1
        // 
        this.columnHeader1.Width = 99;
        // 
        // columnHeader2
        // 
        this.columnHeader2.Width = 117;
        // 
        // columnHeader3
        // 
        this.columnHeader3.Width = 117;
        // 
        // Form1
        // 
        this.ClientSize = new System.Drawing.Size(528, 261);
        this.Controls.Add(this.listView1);
        this.Controls.Add(this.button1);
        this.Name = "Form1";
        this.ResumeLayout(false);

    }

    #endregion

    private System.Windows.Forms.VScrollBar vScrollBar1;
    private System.Windows.Forms.TextBox textBox1;
    private System.Windows.Forms.TextBox textBox2;
    private System.Windows.Forms.Button button1;
    private System.Windows.Forms.ListView listView1;
    private System.Windows.Forms.ColumnHeader columnHeader1;
    private System.Windows.Forms.ColumnHeader columnHeader2;
    private System.Windows.Forms.ColumnHeader columnHeader3;

    public ProgressBar LvAddProgB(ListView LV, int X, int Y, string lvName)
    {
        ProgressBar ProgBar = new ProgressBar();
        ProgBar.Parent = LV;
        ProgBar.Name = lvName;
        ProgBar.Location = new Point(X, Y);
        ProgBar.Visible = true;
        ProgBar.Maximum = 1000;
        ProgBar.Step = 1;

        return ProgBar;
    }

    private void button1_Click(object sender, EventArgs e)
    {
        for (int x = 0; x < 3; ++x)
        {
            ListViewItem item = new ListViewItem();
            item.Text = "d.Name";
            item.SubItems.Add("                 ");
            listView1.Items.Add(item);
            listView1.Controls.Add(LvAddProgB(listView1, item.Position.X + item.Bounds.Width, item.Position.Y, "Lview" + x.ToString()));
        }
    }

在ListView中访问ProgressBar

2 个答案: