prs/prs.mobile.new/PRS.Mobile/Components/DigitalForms/Editor/CustomUserControls/CustomPickeriOS.xaml.cs

using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Collections.Specialized;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Xamarin.Essentials;
using Xamarin.Forms;
using Xamarin.Forms.Xaml;

namespace PRS.Mobile
{
    public delegate void CustomPickeriOSValueChanged();

    [XamlCompilation(XamlCompilationOptions.Compile)]
    public partial class CustomPickeriOS : ContentView
    {
        public event CustomPickeriOSValueChanged CustomPickeriOSValueChanged;
        public string Title { get; set; }
        public List<string> StringList { get; set; }
        public int SelectedIndex { get; set; }
        public string SelectedItem { get; set; }
        List<PickerOption> Options = new List<PickerOption>();
        double fixedHeight = 0;
        //public JobDocFilterType Type { get; set; }
        public CustomPickeriOS()
        {
            InitializeComponent();
            Title = "";
            SelectedItem = "";
            StringList = new List<string>();
            SelectedIndex = -1;
            var mainDisplayInfo = DeviceDisplay.MainDisplayInfo;
            fixedHeight = (mainDisplayInfo.Height / 4) * 3;
        }

        public void SetDefault(string s)
        {
            selectBtn.Text = s;
        }

        public void SetBackGroundColor(Color color)
        {
            selectBtn.BackgroundColor = color;
        }

        public void AddItems(List<string> items, string defaultText = "")
        {
            foreach (string s in items)
            {
                StringList.Add(s);
                PickerOption option = new PickerOption { OptionString = s };
                Options.Add(option);
            }
            listView.ItemsSource = Options;

            if (!string.IsNullOrWhiteSpace(defaultText))
            {
                selectBtn.Text = defaultText;
                SelectedItem = defaultText;
            }
        }

        void SelectBtn_Clicked(object sender, EventArgs e)
        {
            Device.BeginInvokeOnMainThread(() =>
            {
                double dynamicHeight = 30 + StringList.Count * 20;
                if (dynamicHeight > fixedHeight)
                    ((this.Parent) as View).HeightRequest = fixedHeight;
                else
                    ((this.Parent) as View).HeightRequest = dynamicHeight;
                listViewRow.Height = new GridLength(1, GridUnitType.Auto);
                buttonRow.Height = new GridLength(0, GridUnitType.Absolute);
                listView.IsVisible = true;
                selectBtn.IsVisible = false;
            });
        }

        void Cell_Tapped(object sender, EventArgs e)
        {
            PickerOption option = listView.SelectedItem as PickerOption;
            SelectedIndex = StringList.IndexOf(option.OptionString);
            selectBtn.Text = option.OptionString;
            listView.IsVisible = false;
            listViewRow.Height = new GridLength(0, GridUnitType.Absolute);
            selectBtn.IsVisible = true;
            SelectedItem = option.OptionString;
            buttonRow.Height = new GridLength(50, GridUnitType.Absolute);
            ((this.Parent) as View).HeightRequest = 50;
            CustomPickeriOSValueChanged?.Invoke();
        }

    }
    public class PickerOption
    {
        public string OptionString { get; set; }
        public PickerOption()
        {
            OptionString = "";
        }
    }
}