src/wp/ContactPicker.xaml.cs

/*
    Licensed to the Apache Software Foundation (ASF) under one
    or more contributor license agreements.  See the NOTICE file
    distributed with this work for additional information
    regarding copyright ownership.  The ASF licenses this file
    to you under the Apache License, Version 2.0 (the
    "License"); you may not use this file except in compliance
    with the License.  You may obtain a copy of the License at

        http://www.apache.org/licenses/LICENSE-2.0

    Unless required by applicable law or agreed to in writing,
    software distributed under the License is distributed on an
    "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
    KIND, either express or implied.  See the License for the
    specific language governing permissions and limitations
    under the License.
*/

namespace WPCordovaClassLib.Cordova.Commands
{
    using System;
    using System.Linq;
    using System.Windows;
    using System.Windows.Controls;
    using System.Windows.Navigation;
    using Microsoft.Phone.Tasks;
    using Microsoft.Phone.UserData;
    using DeviceContacts = Microsoft.Phone.UserData.Contacts;

    /// <summary>
    /// Custom implemented class for picking single contact
    /// </summary>
    public partial class ContactPicker
    {
        #region Fields

        /// <summary>
        /// Result of ContactPicker call, represent contact returned.
        /// </summary>
        private ContactPickerTask.PickResult result;

        #endregion

        #region Constructors

        /// <summary>
        /// Initializes a new instance of the <see cref="ContactPicker"/> class. 
        /// </summary>
        public ContactPicker()
        {
            InitializeComponent();
            var cons = new DeviceContacts();
            cons.SearchCompleted += this.OnSearchCompleted;
            cons.SearchAsync(string.Empty, FilterKind.None, string.Empty);
        }

        #endregion

        #region Callbacks

        /// <summary>
        /// Occurs when contact is selected or pick operation cancelled.
        /// </summary>
        public event EventHandler<ContactPickerTask.PickResult> Completed;

        #endregion

        /// <summary>
        /// The on navigated from.
        /// </summary>
        /// <param name="e">
        /// The e.
        /// </param>
        protected override void OnNavigatedFrom(NavigationEventArgs e)
        {
            if (this.result == null)
            {
                this.Completed(this, new ContactPickerTask.PickResult(TaskResult.Cancel));
            }

            base.OnNavigatedFrom(e);
        }

        /// <summary>
        /// Called when contacts retrieval completed.
        /// </summary>
        /// <param name="sender">The sender.</param>
        /// <param name="e">The <see cref="ContactsSearchEventArgs"/> instance containing the event data.</param>
        private void OnSearchCompleted(object sender, ContactsSearchEventArgs e)
        {
            if (e.Results.Count() != 0)
            {
                lstContacts.ItemsSource = e.Results.ToList();
                lstContacts.Visibility = Visibility.Visible;
                NoContactsBlock.Visibility = Visibility.Collapsed;
            }
            else
            {
                lstContacts.Visibility = Visibility.Collapsed;
                NoContactsBlock.Visibility = Visibility.Visible;
            }
        }

        /// <summary>
        /// Called when any contact is selected.
        /// </summary>
        /// <param name="sender">
        /// The sender.
        /// </param>
        /// <param name="e">
        /// The e.
        /// </param>
        private void ContactsListSelectionChanged(object sender, SelectionChangedEventArgs e)
        {
            this.result = new ContactPickerTask.PickResult(TaskResult.OK) { Contact = e.AddedItems[0] as Contact };
            this.Completed(this, this.result);

            if (NavigationService.CanGoBack)
            {
                NavigationService.GoBack();
            }
        }
    }
}