IEditableCollectionViewAddNewItem.AddNewItem(Object) Method

Definition

Namespace:

System.ComponentModel

Assembly:

WindowsBase.dll

Adds the specified object to the collection.

public:
 System::Object ^ AddNewItem(System::Object ^ newItem);

public object AddNewItem (object newItem);

abstract member AddNewItem : obj -> obj

Public Function AddNewItem (newItem As Object) As Object

Parameters

newItem

Object

The object to add to the collection.

Returns

Object

The object that is added to the collection.

Examples

The following example calls the AddNewItem method to add an object to a collection. For the complete example, see the IEditableCollectionViewAddNewItem class.

using System;
using System.ComponentModel;
using System.Windows;

namespace IEditableCollectionViewAddItemExample
{
    public partial class Window1 : Window
    {
        public Window1()
        {
            InitializeComponent();
        }

        private void Button_Click(object sender, RoutedEventArgs e)
        {
            IEditableCollectionViewAddNewItem viewToAddDisparateItems =
                catalogList.Items as IEditableCollectionViewAddNewItem;

            if (!viewToAddDisparateItems.CanAddNewItem)
            {
                MessageBox.Show("You cannot add items to the list.");
                return;
            }

            // Create a window that prompts the user to enter a new
            // item to sell.
            AddItemWindow win = new AddItemWindow();

            // Create an item, depending on which RadioButton is selected.
            // Radio buttons correspond to book, cd, dvd, or other.
            LibraryItem newItem;

            if ((bool)book.IsChecked)
            {
                newItem = new Book("Enter the book title", "Enter an Author", "Enter a Genre",
                    "Enter a call number", DateTime.Now + new TimeSpan(21, 0, 0, 0));
            }
            else if ((bool)cd.IsChecked)
            {
                newItem = new MusicCD("Enter the Album", "Enter the artist", 0, "CD.******",
                    DateTime.Now + new TimeSpan(14, 0, 0, 0));
            }

            else if ((bool)dvd.IsChecked)
            {
                newItem = new MovieDVD("Enter the movie title", "Enter the director",
                    "Enter the genre", new TimeSpan(), "DVD.******",
                    DateTime.Now + new TimeSpan(7, 0, 0, 0));
            }
            else
            {
                newItem = new LibraryItem("Enter the title", "Enter the call number",
                        DateTime.Now + new TimeSpan(14, 0, 0, 0));
            }

            // Add the new item to the collection by calling
            // IEditableCollectionViewAddNewItem.AddNewItem.
            // Set the DataContext of the AddItemWindow to the
            // returned item.
            win.DataContext = viewToAddDisparateItems.AddNewItem(newItem);

            // If the user submits the new item, commit the new
            // object to the collection.  If the user cancels 
            // adding the new item, discard the new item.
            if ((bool)win.ShowDialog())
            {
                viewToAddDisparateItems.CommitNew();
            }
            else
            {
                viewToAddDisparateItems.CancelNew();
            }
        }
    }
}

Imports System.ComponentModel
Imports System.Windows

Partial Class Window1
    Public Sub New()
        InitializeComponent()
    End Sub

    Private Sub Button_Click(ByVal sender As Object, ByVal e As RoutedEventArgs)

        Dim viewToAddDisparateItems As IEditableCollectionViewAddNewItem =
            TryCast(catalogList.Items, IEditableCollectionViewAddNewItem)

        If Not viewToAddDisparateItems.CanAddNewItem Then
            MessageBox.Show("You cannot add items to the list.")
            Exit Sub
        End If

        ' Create a window that prompts the user to enter a new 
        ' item to sell. 
        Dim win As New AddItemWindow()

        ' Create an item, depending on which RadioButton is selected. 
        ' Radio buttons correspond to book, cd, dvd, or other. 
        Dim newItem As LibraryItem

        If CBool(Book.IsChecked) Then
            newItem = New Book("Enter the book title", "Enter an Author",
                "Enter a Genre", "Enter a call number",
                DateTime.Now + New TimeSpan(21, 0, 0, 0))
        ElseIf CBool(cd.IsChecked) Then
            newItem = New MusicCD("Enter the Album", "Enter the artist",
                0, "CD.******", DateTime.Now + New TimeSpan(14, 0, 0, 0))

        ElseIf CBool(dvd.IsChecked) Then
            newItem = New MovieDVD("Enter the movie title",
                "Enter the director", "Enter the genre", New TimeSpan(),
                "DVD.******", DateTime.Now + New TimeSpan(7, 0, 0, 0))
        Else
            newItem = New LibraryItem("Enter the title",
                "Enter the call number",
                DateTime.Now + New TimeSpan(14, 0, 0, 0))
        End If

        ' Add the new item to the collection by calling 
        ' IEditableCollectionViewAddNewItem.AddNewItem. 
        ' Set the DataContext of the AddItemWindow to the 
        ' returned item. 
        win.DataContext = viewToAddDisparateItems.AddNewItem(newItem)

        ' If the user submits the new item, commit the new 
        ' object to the collection. If the user cancels 
        ' adding the new item, discard the new item. 
        If CBool(win.ShowDialog()) Then
            viewToAddDisparateItems.CommitNew()
        Else
            viewToAddDisparateItems.CancelNew()
        End If
    End Sub
End Class

Remarks

When you calling the AddNewItem method, it begins an add transaction. You should call the CommitNew or CancelNew methods to end the add transaction.

A new item always appears in the collection view. Any filtering, sorting, or grouping that is applied to the view is applied to the new item when CommitNew is called.