AutoCompleteEdit.TextChanged Event

Fires when the edit box text is changed.

Namespace: DevExpress.XamarinForms.Editors

Assembly: DevExpress.XamarinForms.Editors.dll

NuGet Package: DevExpress.XamarinForms.Editors

Declaration

public event EventHandler<AutoCompleteEditTextChangedEventArgs> TextChanged

Event Data

The TextChanged event's data class is AutoCompleteEditTextChangedEventArgs. The following properties provide information specific to this event:

Property	Description
Reason	Gets a value that specifies how the text in an AutoCompleteEdit was changed.

Remarks

The TextChanged event fires when the Text property value changes. Use the Reason event argument to determine how the text was changed and respond to the change:

• UserInput — a user changed the text.
• SuggestionChosen — a user selected a suggestion in the drop-down list.
• ProgrammaticChange — the text was changed in code.

Example

The code below handles the TextChanged event to supply suggestions.

XAML

<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             xmlns:dxe="http://schemas.devexpress.com/xamarin/2014/forms/editors"
             xmlns:local="clr-namespace:DemoCenter.Forms.Views"
             x:Class="DemoCenter.Forms.Views.AutoCompleteEditView">
    <ContentPage.BindingContext>
        <local:AutoCompleteEditViewModel/>
    </ContentPage.BindingContext>
    <ContentPage.Content>
        <dxe:AutoCompleteEdit TextChanged="AutoCompleteEdit_TextChanged" 
                              ItemsSource="{Binding ItemsSource}"
                              LoadingProgressMode="Manual"/>
    </ContentPage.Content>
</ContentPage>

C#

using System;
using System.ComponentModel;
using System.Linq;
using System.Threading.Tasks;
using DevExpress.XamarinForms.Editors;

namespace DemoCenter.Forms.Views {
    // View
    public partial class AutoCompleteEditView : ContentPage {
        private void AutoCompleteEdit_TextChanged(object sender, DevExpress.XamarinForms.Editors.AutoCompleteEditTextChangedEventArgs e) {
            AutoCompleteEdit edit = sender as AutoCompleteEdit;
            AutoCompleteEditViewModel viewModel = edit.BindingContext as AutoCompleteEditViewModel;
            if (e.Reason == DevExpress.XamarinForms.Editors.AutoCompleteEditTextChangeReason.UserInput) {
                edit.IsLoadingInProgress = true;
                Task.Factory.StartNew(new Action(() => {
                    Thread.Sleep(3000);
                    Dispatcher.BeginInvokeOnMainThread(new Action(() => {
                        viewModel.ItemsSource = Model.Queries.Where(i => i.Contains(edit.Text)).ToList<string>();
                        edit.IsLoadingInProgress = false;
                    }));
                }));
            }
        }
    }
    // View Model
    public class AutoCompleteEditViewModel : INotifyPropertyChanged {
        List<string> itemsSource = new List<string>();
        public List<string> ItemsSource { get { return itemsSource; } set { itemsSource = value; OnPropertyChanged(nameof(ItemsSource)); } }

        public event PropertyChangedEventHandler PropertyChanged;
        protected void OnPropertyChanged(string propertyName) {
            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
        }
    }
    // Model
    class Model {
        public static List<string> Queries = new List<string>();
        static Model() {
            Queries.Add("California");
            Queries.Add("Colorado");
            Queries.Add("Connecticut");
        }
    }
}