Creating columns in listView and add items

Question

I'm learning how to use the listView in a windowsForm and I have some problems that I hope to solve here. The first thing is when I'm creating the columns with the code below:

private void initListView()
    {
        // Add columns
        lvRegAnimals.Columns.Add("Id", -3,HorizontalAlignment.Left);
        lvRegAnimals.Columns.Add("Name", -3, HorizontalAlignment.Left);
        lvRegAnimals.Columns.Add("Age", -3, HorizontalAlignment.Left);
    }

When I run the program, the name of the columns are not visible, they are all at the left corner, and I have to "drag" them to be able to read the text. What have I done wrong?

And finally I wonder how I add items to the columns. Do I first create a object like

ListViewItem item1 = new ListViewItem(???);
item1.SubItems.Add("text");

Is each listViewItem objects a column or a row? How do I add rows of info? Preciate some help! Thanks!

Answer 1

Your first problem is that you are passing -3 to the 2nd parameter of Columns.Add. It needs to be -2 for it to auto-size the column. Source: http://msdn.microsoft.com/en-us/library/system.windows.forms.listview.columns.aspx (look at the comments on the code example at the bottom)

private void initListView()
{
    // Add columns
    lvRegAnimals.Columns.Add("Id", -2,HorizontalAlignment.Left);
    lvRegAnimals.Columns.Add("Name", -2, HorizontalAlignment.Left);
    lvRegAnimals.Columns.Add("Age", -2, HorizontalAlignment.Left);
}

You can also use the other overload, Add(string). E.g:

lvRegAnimals.Columns.Add("Id");
lvRegAnimals.Columns.Add("Name");
lvRegAnimals.Columns.Add("Age");

Reference for more overloads: http://msdn.microsoft.com/en-us/library/system.windows.forms.listview.columnheadercollection.aspx

Second, to add items to the ListView, you need to create instances of ListViewItem and add them to the listView's Items collection. You will need to use the string[] constructor.

var item1 = new ListViewItem(new[] {"id123", "Tom", "24"});
var item2 = new ListViewItem(new[] {person.Id, person.Name, person.Age});
lvRegAnimals.Items.Add(item1);
lvRegAnimals.Items.Add(item2);

You can also store objects in the item's Tag property.

item2.Tag = person;

And then you can extract it

var person = item2.Tag as Person;

Let me know if you have any questions and I hope this helps!