private static void OnDisplayPropertyChanged(BindableObject bindable, object oldValue, object newValue)
{
ExtendedPicker bindablePicker = (ExtendedPicker)bindable;
bindablePicker.DisplayProperty = (string)newValue;
loadItemsAndSetSelected(bindable);
}
private static void OnItemsSourceChanged(BindableObject bindable, object oldValue, object newValue)
{
ExtendedPicker bindablePicker = (ExtendedPicker)bindable;
bindablePicker.ItemsSource = (IList)newValue;
loadItemsAndSetSelected(bindable);
}
public App()
{
var extenderPicker = new ExtendedPicker ();
extenderPicker.ItemsSource = new List<Color>{ Color.Aqua, Color.Black };
// The root page of your application
MainPage = new ExtendedPickerPage();
}
private static void OnSelectedItemChanged(BindableObject bindable, object oldValue, object newValue)
{
ExtendedPicker bindablePicker = (ExtendedPicker)bindable;
bindablePicker.SelectedItem = newValue;
if (bindablePicker.ItemsSource != null && bindablePicker.SelectedItem != null)
{
int count = 0;
foreach (object obj in bindablePicker.ItemsSource)
{
if (obj == bindablePicker.SelectedItem)
{
bindablePicker.SelectedIndex = count;
break;
}
count++;
}
}
}
public ExtendedPickerPage()
{
InitializeComponent ();
BindingContext = this;
myPicker = new ExtendedPicker (){DisplayProperty = "FirstName"};
myPicker.SetBinding(ExtendedPicker.ItemsSourceProperty,new Binding("MyDataList",BindingMode.TwoWay));
myPicker.SetBinding(ExtendedPicker.SelectedItemProperty,new Binding("TheChosenOne",BindingMode.TwoWay));
myStackLayout.Children.Add (new Label{ Text = "Code Created:" });
myStackLayout.Children.Add (myPicker);
TheChosenOne = new DataClass(){ FirstName = "Jet", LastName = "Li" };
MyDataList = new ObservableCollection<object> () {
new DataClass(){FirstName="Jack",LastName="Doe"},
TheChosenOne,
new DataClass(){FirstName="Matt",LastName="Bar"},
new DataClass(){FirstName="Mic",LastName="Jaggery"},
new DataClass(){FirstName="Michael",LastName="Jackon"}
};
}
static void loadItemsAndSetSelected(BindableObject bindable)
{
ExtendedPicker bindablePicker = (ExtendedPicker)bindable;
if (bindablePicker.ItemsSource as IEnumerable != null)
{
PropertyInfo propertyInfo = null;
int count = 0;
foreach (object obj in (IEnumerable)bindablePicker.ItemsSource)
{
string value = string.Empty;
if (bindablePicker.DisplayProperty != null)
{
if (propertyInfo == null)
{
propertyInfo = obj.GetType().GetRuntimeProperty(bindablePicker.DisplayProperty);
if (propertyInfo == null)
{
throw new Exception(String.Concat(bindablePicker.DisplayProperty, " is not a property of ", obj.GetType().FullName));
}
}
value = propertyInfo.GetValue(obj).ToString();
}
else
{
value = obj.ToString();
}
bindablePicker.Items.Add(value);
if (bindablePicker.SelectedItem != null)
{
if (bindablePicker.SelectedItem == obj)
{
bindablePicker.SelectedIndex = count;
}
}
count++;
}
}
}
private static void OnSelectedItemChanged(BindableObject bindable, object oldValue, object newValue)
{
ExtendedPicker bindablePicker = (ExtendedPicker)bindable;
ExtendedPicker picker = bindable as ExtendedPicker;
if (picker != null)
{
var selectedItem = picker.ItemsSource[picker.SelectedIndex];
if (!string.IsNullOrWhiteSpace(picker.KeyMemberPath))
{
var keyProperty = selectedItem.GetType().GetRuntimeProperty(picker.KeyMemberPath);
if (keyProperty == null)
{
throw new InvalidOperationException(String.Concat(picker.KeyMemberPath, " is not a property of ",
selectedItem.GetType().FullName));
}
picker.SelectedItem = keyProperty.GetValue(selectedItem);
}
else
{
picker.SelectedItem = selectedItem.ToString();
}
}
if (bindablePicker.ItemsSource != null && bindablePicker.SelectedItem != null)
{
int count = 0;
foreach (object obj in bindablePicker.ItemsSource)
{
if (obj == bindablePicker.SelectedItem)
{
bindablePicker.SelectedIndex = count;
break;
}
count++;
}
}
}
private static void OnKeyMemberPathChanged(BindableObject bindable, object oldValue, object newValue)
{
ExtendedPicker picker = bindable as ExtendedPicker;
picker.KeyMemberPath = newValue?.ToString();
}
private static void OnItemsSourceChanged(BindableObject bindable, object oldValue, object newValue)
{
bindablePicker = (ExtendedPicker)bindable;
bindablePicker.ItemsSource = (IList)newValue;
loadItems(bindable);
observable = newValue as INotifyCollectionChanged;
if (observable != null)
{
observable.CollectionChanged += observable_CollectionChanged;
}
}