void UpdateItems()
{
// supress notification of non-user generated events (e.g. adding\syncing list values)
_isChanging = true;
FormsListPicker picker = _listPicker;
// add/remove slots from control to match element
while (picker.Items.Count < Element.Items.Count + 1)
{
picker.Items.Add(new ItemViewModel(string.Empty));
}
while (picker.Items.Count > Element.Items.Count + 1)
{
picker.Items.RemoveAt(picker.Items.Count - 1);
}
// update all control values to match element values
for (var i = 0; i < Element.Items.Count; i++)
{
var item = (ItemViewModel)picker.Items[i + 1];
if (item.Data == Element.Items[i])
{
continue;
}
item.Data = Element.Items[i];
}
picker.SelectedIndex = Element.SelectedIndex + 1;
_isChanging = false;
}
protected override void OnElementChanged(ElementChangedEventArgs <Picker> e)
{
_listPicker = new FormsListPicker();
UpdateAlignment();
UpdateIsEnabled();
base.OnElementChanged(e);
if (e.OldElement != null)
{
((ObservableList <string>)Element.Items).CollectionChanged -= ItemsCollectionChanged;
}
((ObservableList <string>)Element.Items).CollectionChanged += ItemsCollectionChanged;
_listPicker.ItemTemplate = (System.Windows.DataTemplate)System.Windows.Application.Current.Resources["PickerItemTemplate"];
_listPicker.FullModeItemTemplate = (System.Windows.DataTemplate)System.Windows.Application.Current.Resources["PickerFullItemTemplate"];
//_listPicker.ExpansionMode = ExpansionMode.FullScreenOnly;
_listPicker.Items.Add(new ItemViewModel(" ")
{
MaxHeight = 0
});
_listPicker.ListPickerModeChanged += ListPickerModeChanged;
_listPicker.Loaded += (sender, args) => {
// The defaults from the control template won't be available
// right away; we have to wait until after the template has been applied
_defaultBrush = _listPicker.Foreground;
UpdateTextColor();
};
var grid = new System.Windows.Controls.Grid {
Children = { _listPicker }, MaxWidth = Device.Info.PixelScreenSize.Width
};
SetNativeControl(grid);
UpdatePicker();
_listPicker.SelectionChanged += PickerSelectionChanged;
}
