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using System;
using System.ComponentModel;
using System.Drawing;
#if __UNIFIED__
using UIKit;
#else
using MonoTouch.UIKit;
#endif
#if __UNIFIED__
using RectangleF = CoreGraphics.CGRect;
using SizeF = CoreGraphics.CGSize;
using PointF = CoreGraphics.CGPoint;
#else
using nfloat=System.Single;
using nint=System.Int32;
using nuint=System.UInt32;
#endif
namespace Xamarin.Forms.Platform.iOS
{
public class PickerRenderer : ViewRenderer<Picker, UITextField>
{
UIPickerView _picker;
UIColor _defaultTextColor;
IElementController ElementController => Element as IElementController;
protected override void OnElementChanged(ElementChangedEventArgs<Picker> e)
{
if (e.OldElement != null)
((ObservableList<string>)e.OldElement.Items).CollectionChanged -= RowsCollectionChanged;
if (e.NewElement != null)
{
if (Control == null)
{
var entry = new NoCaretField { BorderStyle = UITextBorderStyle.RoundedRect };
entry.Started += OnStarted;
entry.Ended += OnEnded;
_picker = new UIPickerView();
var width = UIScreen.MainScreen.Bounds.Width;
var toolbar = new UIToolbar(new RectangleF(0, 0, width, 44)) { BarStyle = UIBarStyle.Default, Translucent = true };
var spacer = new UIBarButtonItem(UIBarButtonSystemItem.FlexibleSpace);
var doneButton = new UIBarButtonItem(UIBarButtonSystemItem.Done, (o, a) =>
{
var s = (PickerSource)_picker.Model;
if (s.SelectedIndex == -1 && Element.Items != null && Element.Items.Count > 0)
UpdatePickerSelectedIndex(0);
UpdatePickerFromModel(s);
entry.ResignFirstResponder();
});
toolbar.SetItems(new[] { spacer, doneButton }, false);
entry.InputView = _picker;
entry.InputAccessoryView = toolbar;
_defaultTextColor = entry.TextColor;
SetNativeControl(entry);
}
_picker.Model = new PickerSource(this);
UpdatePicker();
UpdateTextColor();
((ObservableList<string>)e.NewElement.Items).CollectionChanged += RowsCollectionChanged;
}
base.OnElementChanged(e);
}
protected override void OnElementPropertyChanged(object sender, PropertyChangedEventArgs e)
{
base.OnElementPropertyChanged(sender, e);
if (e.PropertyName == Picker.TitleProperty.PropertyName)
UpdatePicker();
if (e.PropertyName == Picker.SelectedIndexProperty.PropertyName)
UpdatePicker();
if (e.PropertyName == Picker.TextColorProperty.PropertyName || e.PropertyName == VisualElement.IsEnabledProperty.PropertyName)
UpdateTextColor();
}
void OnEnded(object sender, EventArgs eventArgs)
{
ElementController.SetValueFromRenderer(VisualElement.IsFocusedPropertyKey, false);
}
void OnStarted(object sender, EventArgs eventArgs)
{
ElementController.SetValueFromRenderer(VisualElement.IsFocusedPropertyKey, true);
}
void RowsCollectionChanged(object sender, EventArgs e)
{
UpdatePicker();
}
void UpdatePicker()
{
var selectedIndex = Element.SelectedIndex;
var items = Element.Items;
Control.Placeholder = Element.Title;
var oldText = Control.Text;
Control.Text = selectedIndex == -1 || items == null ? "" : items[selectedIndex];
UpdatePickerNativeSize(oldText);
_picker.ReloadAllComponents();
if (items == null || items.Count == 0)
return;
UpdatePickerSelectedIndex(selectedIndex);
}
void UpdatePickerFromModel(PickerSource s)
{
if (Element != null)
{
var oldText = Control.Text;
ElementController.SetValueFromRenderer(Picker.SelectedIndexProperty, s.SelectedIndex);
Control.Text = s.SelectedItem;
UpdatePickerNativeSize(oldText);
}
}
void UpdatePickerNativeSize(string oldText)
{
if (oldText != Control.Text)
((IVisualElementController)Element).NativeSizeChanged();
}
void UpdatePickerSelectedIndex(int formsIndex)
{
var source = (PickerSource)_picker.Model;
source.SelectedIndex = formsIndex;
source.SelectedItem = formsIndex >= 0 ? Element.Items[formsIndex] : null;
_picker.Select(Math.Max(formsIndex, 0), 0, true);
}
void UpdateTextColor()
{
var textColor = Element.TextColor;
if (textColor.IsDefault || !Element.IsEnabled)
Control.TextColor = _defaultTextColor;
else
Control.TextColor = textColor.ToUIColor();
}
class PickerSource : UIPickerViewModel
{
readonly PickerRenderer _renderer;
public PickerSource(PickerRenderer model)
{
_renderer = model;
}
public int SelectedIndex { get; internal set; }
public string SelectedItem { get; internal set; }
public override nint GetComponentCount(UIPickerView picker)
{
return 1;
}
public override nint GetRowsInComponent(UIPickerView pickerView, nint component)
{
return _renderer.Element.Items != null ? _renderer.Element.Items.Count : 0;
}
public override string GetTitle(UIPickerView picker, nint row, nint component)
{
return _renderer.Element.Items[(int)row];
}
public override void Selected(UIPickerView picker, nint row, nint component)
{
if (_renderer.Element.Items.Count == 0)
{
SelectedItem = null;
SelectedIndex = -1;
}
else
{
SelectedItem = _renderer.Element.Items[(int)row];
SelectedIndex = (int)row;
}
_renderer.UpdatePickerFromModel(this);
}
}
}
}
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