using System;
using System.Collections;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.ComponentModel;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Xamarin.Forms;
namespace CascadingPicker
{
public partial class MainPage : ContentPage
{
string CurrentItem;
public MainPage()
{
InitializeComponent();
}
private void picker_SelectionChanged(object sender, Syncfusion.SfPicker.XForms.SelectionChangedEventArgs e)
{
if (picker.ItemsSource != null && e.NewValue is IList && (picker.ItemsSource as IList).Count > 1 && CurrentItem != (e.NewValue as IList)[0].ToString())
{
//Updated the second column collection based on first column selected value.
(picker.ItemsSource as ObservableCollection<object>).RemoveAt(1);
(picker.ItemsSource as ObservableCollection<object>).Add(GetCountry((e.NewValue as IList)[0].ToString()));
}
}
public ObservableCollection<object> GetCountry(string CountryName)
{
CurrentItem = CountryName;
ObservableCollection<object> selectedCountries = new ObservableCollection<object>();
if (CountryName == "UK")
{
selectedCountries.Add("London");
selectedCountries.Add("Manchester");
selectedCountries.Add("Cambridge");
selectedCountries.Add("Edinburgh");
selectedCountries.Add("Glasgow");
selectedCountries.Add("Birmingham");
}
else if (CountryName == "USA")
{
selectedCountries.Add("New York");
selectedCountries.Add("Seattle");
selectedCountries.Add("Wasington");
selectedCountries.Add("Chicago");
selectedCountries.Add("Boston");
selectedCountries.Add("Los Angles");
}
else if (CountryName == "UAE")
{
selectedCountries.Add("Dubai");
selectedCountries.Add("Abu Dhabi");
selectedCountries.Add("Fujairah");
selectedCountries.Add("Sharjah");
selectedCountries.Add("Ajman");
selectedCountries.Add("AL Ain");
}
else if (CountryName == "India")
{
selectedCountries.Add("Mumbai");
selectedCountries.Add("Bengaluru");
selectedCountries.Add("Chennai");
selectedCountries.Add("Pune");
selectedCountries.Add("Jaipur");
selectedCountries.Add("Delhi");
}
else
{
selectedCountries.Add("Berlin");
selectedCountries.Add("Munich");
selectedCountries.Add("Frankfurt");
selectedCountries.Add("Hamburg");
selectedCountries.Add("Cologne");
selectedCountries.Add("Bonn");
}
return selectedCountries;
}
private void Button_Clicked(object sender, EventArgs e)
{
picker.IsOpen = true;
}
}
public class PickerCascading : INotifyPropertyChanged
{
#region Public Properties
/// <summary>
/// Area is the acutal DataSource for SfPicker control which will holds the collection of Country and State
/// </summary>
/// <value>The area.</value>
public ObservableCollection<object> Area { get; set; }
//Country is the collection of country names
private ObservableCollection<object> Country { get; set; }
//State is the collection of state names
private ObservableCollection<object> State { get; set; }
/// <summary>
/// Headers api is holds the column name for every column in cascading picker
/// </summary>
/// <value>The Headers.</value>
public ObservableCollection<string> Header { get; set; }
private object _selectedarea;
public event PropertyChangedEventHandler PropertyChanged;
#endregion
//Identify the selected area using property changed method
public object SelectedArea
{
get { return _selectedarea; }
set { _selectedarea = value; RaisePropertyChanged("SelectedArea"); }
}
public PickerCascading()
{
Area = new ObservableCollection<object>();
Header = new ObservableCollection<string>();
Country = new ObservableCollection<object>();
State = new ObservableCollection<object>();
//populate Countries
Country.Add("UK");
Country.Add("USA");
Country.Add("India");
Country.Add("UAE");
Country.Add("Germany");
//populate states
State.Add("London");
State.Add("Manchester");
State.Add("Cambridge");
State.Add("Edinburgh");
State.Add("Glasgow");
State.Add("Birmingham");
Area.Add(Country);
Area.Add(State);
Header.Add("Country");
Header.Add("State");
SelectedArea = new ObservableCollection<object>() { "UK", "London" };
}
//Hooked when changes occured
public void RaisePropertyChanged(string name)
{
if (PropertyChanged != null)
PropertyChanged(this, new PropertyChangedEventArgs(name));
}
}
}
