Xamarin.Forms Autocomplete CrossPlatform

Question

I am a newbie to Xamarin.Forms Platform. I hope you can help me in moving ahead. I want to have a control like autocomplete in xamarin.forms like below

Can

Answer 1

I have implemented an AutocompleteView in my project. You can refer it.

public class AutoCompleteView : ContentView
{
    public static readonly BindableProperty SuggestionsProperty = BindableProperty.Create(nameof(Suggestions), typeof(IEnumerable), typeof(AutoCompleteView), null, BindingMode.OneWay, null, OnSuggestionsChanged);
    public static readonly BindableProperty SearchTextProperty = BindableProperty.Create(nameof(SearchText), typeof(string), typeof(AutoCompleteView), null, BindingMode.TwoWay, null, OnSearchTextChanged);
    public static readonly BindableProperty PlaceholderProperty = BindableProperty.Create(nameof(Placeholder), typeof(string), typeof(AutoCompleteView), null, BindingMode.OneWay, null, OnPlaceholderChanged);
    public static readonly BindableProperty MaximumVisibleSuggestionItemsProperty = BindableProperty.Create(nameof(MaximumVisibleSuggestionItems), typeof(int), typeof(AutoCompleteView), 4);
    public static readonly BindableProperty SuggestionItemTemplateProperty = BindableProperty.Create(nameof(SuggestionItemTemplate), typeof(DataTemplate), typeof(AutoCompleteView), null, BindingMode.OneWay, null, OnSuggestionItemTemplateChanged);
    public static readonly BindableProperty DisplayPropertyNameProperty = BindableProperty.Create(nameof(DisplayPropertyName), typeof(string), typeof(AutoCompleteView));

    public IEnumerable Suggestions
    {
        get { return (IEnumerable)GetValue(SuggestionsProperty); }
        set { SetValue(SuggestionsProperty, value); }
    }

    public string SearchText
    {
        get { return (string)GetValue(SearchTextProperty); }
        set { SetValue(SearchTextProperty, value); }
    }

    public string Placeholder
    {
        get { return (string)GetValue(PlaceholderProperty); }
        set { SetValue(PlaceholderProperty, value); }
    }

    public int MaximumVisibleSuggestionItems
    {
        get { return (int)GetValue(MaximumVisibleSuggestionItemsProperty); }
        set { SetValue(MaximumVisibleSuggestionItemsProperty, value); }
    }

    public DataTemplate SuggestionItemTemplate
    {
        get { return (DataTemplate)GetValue(SuggestionItemTemplateProperty); }
        set { SetValue(SuggestionItemTemplateProperty, value); }
    }

    public string DisplayPropertyName
    {
        get { return (string)GetValue(DisplayPropertyNameProperty); }
        set { SetValue(DisplayPropertyNameProperty, value); }
    }

    public ItemsStack SuggestionsListView { get; private set; }
    public Entry SearchEntry { get; private set; }
    public IEnumerable OriginSuggestions { get; private set; }
    public NestedScrollView SuggestionWrapper { get; private set; }
    public Grid Container { get; private set; }

    public bool IsSelected { get; private set; }
    public int TotalNumberOfTypings { get; private set; }

    private static void OnSuggestionsChanged(object bindable, object oldValue, object newValue)
    {
        var autoCompleteView = bindable as AutoCompleteView;

        var suggestions = (IEnumerable)newValue;
        autoCompleteView.OriginSuggestions = suggestions;

        suggestions = autoCompleteView.FilterSuggestions(suggestions, autoCompleteView.SearchText);
        autoCompleteView.SuggestionsListView.ItemsSource = suggestions;
    }

    private static void OnSearchTextChanged(object bindable, object oldValue, object newValue)
    {
        var autoCompleteView = bindable as AutoCompleteView;

        var suggestions = autoCompleteView.OriginSuggestions;
        if (newValue != null)
        {
            suggestions = autoCompleteView.FilterSuggestions(suggestions, autoCompleteView.SearchText);
            // assign when initializing with data
            if (autoCompleteView.SearchEntry.Text != autoCompleteView.SearchText)
            {
                autoCompleteView.SearchEntry.Text = autoCompleteView.SearchText;
            }
        }
        autoCompleteView.SuggestionsListView.ItemsSource = suggestions;

        if (Device.OS == TargetPlatform.Android)
        {
            // update the layout -> only do this when user is typing instead of selection an item from suggestions list 
            // -> prevent duplicated update layout
            if (!autoCompleteView.IsSelected)
            {
                autoCompleteView.UpdateLayout();
            }
            else
            {
                autoCompleteView.IsSelected = false;
            }
        }
    }

    private static void OnSuggestionItemTemplateChanged(object bindable, object oldValue, object newValue)
    {
        var autoCompleteView = bindable as AutoCompleteView;

        if (autoCompleteView.SuggestionsListView != null)
        {
            autoCompleteView.SuggestionsListView.ItemTemplate = autoCompleteView.SuggestionItemTemplate;
        }
    }

    public IEnumerable FilterSuggestions(IEnumerable suggestions, string keyword)
    {
        if (string.IsNullOrEmpty(keyword) || suggestions == null) return suggestions;

        var searchWords = keyword.ConvertToNonMark().ToLower().Split(new string[] { " " }, StringSplitOptions.RemoveEmptyEntries);
        var result = suggestions.Cast