在ListView中访问ProgressBar

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,则可以将其从Controls集合中删除以进行更新.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项的方法ProgressBar.

假设您ListView是Details视图,只需在末尾添加一个子项,而不是相关的ColumnHeader.数据不会显示,但仍与项目相关.使用与ProgressBar名称相同的文本,很容易找到.

我ListView有3列:{Item, Name, Completion},但代码将添加第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);