C# 在MvvmCross+中选择Bindable Picker的EdItem不在Bindable stackLayout内工作；沙马林型_C#_Asp.net Mvc_Xamarin.forms

C# 在MvvmCross+中选择Bindable Picker的EdItem不在Bindable stackLayout内工作；沙马林型

c# asp.net-mvc xamarin.forms

C# 在MvvmCross+中选择Bindable Picker的EdItem不在Bindable stackLayout内工作；沙马林型,c#,asp.net-mvc,xamarin.forms,C#,Asp.net Mvc,Xamarin.forms,视图模型： List<PictureModel> _pages; public List<PictureModel> Pages { get { return _pages; } set { _pages = value; RaisePropertyChanged(() => Pages);

视图模型：

    List<PictureModel> _pages;
    public List<PictureModel> Pages
    {
        get
        {
            return _pages;
        }
        set
        {
            _pages = value;
            RaisePropertyChanged(() => Pages);
            CurrentPage = Pages.FirstOrDefault();
        }
    }

    private AttributeValue _selectedAttributeValue;

    public AttributeValue SelectedAttributeValue
    {
        get { return _selectedAttributeValue; }
        set
        {
            _selectedAttributeValue = value;
            RaisePropertyChanged(() => SelectedAttributeValue);
            SelectedAttributeCommand.Execute(null);

        }
    }

    public ICommand SelectedAttributeCommand
    {
        get
        {
            //return new MvxCommand(() => ShowViewModel<ReviewsPageViewModel>());
            return new MvxCommand(() =>
            {
                ChangePresentation(new MvxClosePresentationHint(new ProductListPageViewModel()));
            });

        }
    }

<controls:AwesomeWrappanel HorizontalOptions="CenterAndExpand"        Orientation="Horizontal" ItemsSource="{Binding ProductDeatil.ProductAttributes}" Spacing="10">
        <controls:AwesomeWrappanel.ItemTemplate>
                <DataTemplate>
                       <controls:BindablePicker ItemsSource="{Binding Values}" 
                         DisplayProperty="Name" Title="{Binding Name}" 
                         SelectedIndex="0" SelectedItem="{Binding 
                         SelectedAttributeValue, Mode=TwoWay}" />           
               </DataTemplate>
        </controls:AwesomeWrappanel.ItemTemplate>
</controls:AwesomeWrappanel>

public class BindablePicker : Picker
{
    public BindablePicker()
    {
        this.SelectedIndexChanged += OnSelectedIndexChanged;
    }


    public static readonly BindableProperty SelectedItemProperty = BindableProperty.Create("SelectedItem", typeof(object), typeof(BindablePicker), null, BindingMode.TwoWay, null, new BindableProperty.BindingPropertyChangedDelegate(BindablePicker.OnSelectedItemChanged), null, null, null);
    public static readonly BindableProperty ItemsSourceProperty = BindableProperty.Create("ItemsSource", typeof(IEnumerable), typeof(BindablePicker), null, BindingMode.TwoWay, null, new BindableProperty.BindingPropertyChangedDelegate(BindablePicker.OnItemsSourceChanged), null, null, null);
    public static readonly BindableProperty DisplayPropertyProperty = BindableProperty.Create("DisplayProperty", typeof(string), typeof(BindablePicker), null, BindingMode.TwoWay, null, new BindableProperty.BindingPropertyChangedDelegate(BindablePicker.OnDisplayPropertyChanged), null, null, null);

    public IList ItemsSource
    {
        get { return (IList)base.GetValue(BindablePicker.ItemsSourceProperty); }
        set { base.SetValue(BindablePicker.ItemsSourceProperty, value); }
    }

    public object SelectedItem
    {
        get { return base.GetValue(BindablePicker.SelectedItemProperty); }
        set
        {
            base.SetValue(BindablePicker.SelectedItemProperty, value);
            if (ItemsSource.Contains(SelectedItem))
            {
                SelectedIndex = ItemsSource.IndexOf(SelectedItem);
            }
            else
            {
                SelectedIndex = -1;
            }
        }
    }

    public string DisplayProperty
    {
        get { return (string)base.GetValue(BindablePicker.DisplayPropertyProperty); }
        set { base.SetValue(BindablePicker.DisplayPropertyProperty, value); }
    }

    private void OnSelectedIndexChanged(object sender, EventArgs e)
    {
        this.SelectedItem = ItemsSource[SelectedIndex];
    }


    private static void OnSelectedItemChanged(BindableObject bindable, object oldValue, object newValue)
    {
        BindablePicker picker = (BindablePicker)bindable;
        picker.SelectedItem = newValue;
        if (picker.ItemsSource != null && picker.SelectedItem != null)
        {
            int count = 0;
            foreach (object obj in picker.ItemsSource)
            {
                if (obj == picker.SelectedItem)
                {
                    picker.SelectedIndex = count;
                    break;
                }
                count++;
            }
        }
    }

    private static void OnDisplayPropertyChanged(BindableObject bindable, object oldValue, object newValue)
    {
        BindablePicker picker = (BindablePicker)bindable;
        picker.DisplayProperty = (string)newValue;
        loadItemsAndSetSelected(bindable);

    }
    private static void OnItemsSourceChanged(BindableObject bindable, object oldValue, object newValue)
    {
        var picker = (BindablePicker)bindable;
        picker.ItemsSource = (IList)newValue;

        var oc = newValue as INotifyCollectionChanged;

        if (oc != null && !PickerLookup.ContainsKey(oc))
        {
            oc.CollectionChanged += Oc_CollectionChanged;
            PickerLookup.Add(oc, new WeakReference(picker));
        }

        loadItemsAndSetSelected(bindable);
    }

    private static readonly Dictionary<INotifyCollectionChanged, WeakReference> PickerLookup = new Dictionary<INotifyCollectionChanged, WeakReference>();

    private static void Oc_CollectionChanged(object sender, NotifyCollectionChangedEventArgs e)
    {
        var oc = (INotifyCollectionChanged)sender;

        if (e.Action == NotifyCollectionChangedAction.Add)
        {
            var picker = (BindablePicker)PickerLookup[oc].Target;

            foreach (var newItem in e.NewItems)
            {
                var value = string.Empty;
                if (picker.DisplayProperty != null)
                {
                    var prop = newItem.GetType().GetRuntimeProperties().FirstOrDefault(p => string.Equals(p.Name, picker.DisplayProperty, StringComparison.OrdinalIgnoreCase));

                    if (prop != null)
                        value = prop.GetValue(newItem).ToString();
                }
                else
                {
                    value = newItem.ToString();
                }

                picker.Items.Add(value);
            }
        }
        else if (e.Action == NotifyCollectionChangedAction.Remove)
        {
            var picker = (BindablePicker)PickerLookup[oc].Target;

            foreach (var newItem in e.OldItems)
            {
                var value = string.Empty;
                if (picker.DisplayProperty != null)
                {
                    var prop = newItem.GetType().GetRuntimeProperties().FirstOrDefault(p => string.Equals(p.Name, picker.DisplayProperty, StringComparison.OrdinalIgnoreCase));

                    if (prop != null)
                        value = prop.GetValue(newItem).ToString();
                }
                else
                {
                    value = newItem.ToString();
                }

                picker.Items.Remove(value);
            }
        }
    }

    static void loadItemsAndSetSelected(BindableObject bindable)
    {

        BindablePicker picker = (BindablePicker)bindable;
        if (picker.ItemsSource as IEnumerable != null)
        {
            int count = 0;
            foreach (object obj in (IEnumerable)picker.ItemsSource)
            {
                string value = string.Empty;
                if (picker.DisplayProperty != null)
                {
                    var prop = obj.GetType().GetRuntimeProperties().FirstOrDefault(p => string.Equals(p.Name, picker.DisplayProperty, StringComparison.OrdinalIgnoreCase));
                    if (prop != null)
                    {
                        value = prop.GetValue(obj).ToString();
                    }
                }
                else
                {
                    value = obj.ToString();
                }
                picker.Items.Add(value);
                if (picker.SelectedItem != null)
                {
                    if (picker.SelectedItem == obj)
                    {
                        picker.SelectedIndex = count;
                    }
                }
                count++;
            }
        }
    }
}

List\u页面；
公共列表页
{
得到
{
返回页面；
}
设置
{
_页数=价值；
RaisePropertyChanged（（）=>页）；
CurrentPage=Pages.FirstOrDefault（）；
}
}
私有属性值_选择属性值；
公共属性值已选择属性值
{
获取{return\u selectedAttributeValue；}
设置
{
_selectedAttributeValue=值；
RaisePropertyChanged（（）=>SelectedAttributeValue）；
SelectedAttributeCommand.Execute（空）；
}
}
公用ICommand，然后选择AttributeCommand
{
得到
{
//返回新的MvxCommand（（）=>ShowViewModel（））；
返回新的MvxCommand（（）=>
{
ChangePresentation（新的MvxClosePresentationHint（新的ProductListPageViewModel（））；
});
}
}

我的XAML文件：

    List<PictureModel> _pages;
    public List<PictureModel> Pages
    {
        get
        {
            return _pages;
        }
        set
        {
            _pages = value;
            RaisePropertyChanged(() => Pages);
            CurrentPage = Pages.FirstOrDefault();
        }
    }

    private AttributeValue _selectedAttributeValue;

    public AttributeValue SelectedAttributeValue
    {
        get { return _selectedAttributeValue; }
        set
        {
            _selectedAttributeValue = value;
            RaisePropertyChanged(() => SelectedAttributeValue);
            SelectedAttributeCommand.Execute(null);

        }
    }

    public ICommand SelectedAttributeCommand
    {
        get
        {
            //return new MvxCommand(() => ShowViewModel<ReviewsPageViewModel>());
            return new MvxCommand(() =>
            {
                ChangePresentation(new MvxClosePresentationHint(new ProductListPageViewModel()));
            });

        }
    }

<controls:AwesomeWrappanel HorizontalOptions="CenterAndExpand"        Orientation="Horizontal" ItemsSource="{Binding ProductDeatil.ProductAttributes}" Spacing="10">
        <controls:AwesomeWrappanel.ItemTemplate>
                <DataTemplate>
                       <controls:BindablePicker ItemsSource="{Binding Values}" 
                         DisplayProperty="Name" Title="{Binding Name}" 
                         SelectedIndex="0" SelectedItem="{Binding 
                         SelectedAttributeValue, Mode=TwoWay}" />           
               </DataTemplate>
        </controls:AwesomeWrappanel.ItemTemplate>
</controls:AwesomeWrappanel>

public class BindablePicker : Picker
{
    public BindablePicker()
    {
        this.SelectedIndexChanged += OnSelectedIndexChanged;
    }


    public static readonly BindableProperty SelectedItemProperty = BindableProperty.Create("SelectedItem", typeof(object), typeof(BindablePicker), null, BindingMode.TwoWay, null, new BindableProperty.BindingPropertyChangedDelegate(BindablePicker.OnSelectedItemChanged), null, null, null);
    public static readonly BindableProperty ItemsSourceProperty = BindableProperty.Create("ItemsSource", typeof(IEnumerable), typeof(BindablePicker), null, BindingMode.TwoWay, null, new BindableProperty.BindingPropertyChangedDelegate(BindablePicker.OnItemsSourceChanged), null, null, null);
    public static readonly BindableProperty DisplayPropertyProperty = BindableProperty.Create("DisplayProperty", typeof(string), typeof(BindablePicker), null, BindingMode.TwoWay, null, new BindableProperty.BindingPropertyChangedDelegate(BindablePicker.OnDisplayPropertyChanged), null, null, null);

    public IList ItemsSource
    {
        get { return (IList)base.GetValue(BindablePicker.ItemsSourceProperty); }
        set { base.SetValue(BindablePicker.ItemsSourceProperty, value); }
    }

    public object SelectedItem
    {
        get { return base.GetValue(BindablePicker.SelectedItemProperty); }
        set
        {
            base.SetValue(BindablePicker.SelectedItemProperty, value);
            if (ItemsSource.Contains(SelectedItem))
            {
                SelectedIndex = ItemsSource.IndexOf(SelectedItem);
            }
            else
            {
                SelectedIndex = -1;
            }
        }
    }

    public string DisplayProperty
    {
        get { return (string)base.GetValue(BindablePicker.DisplayPropertyProperty); }
        set { base.SetValue(BindablePicker.DisplayPropertyProperty, value); }
    }

    private void OnSelectedIndexChanged(object sender, EventArgs e)
    {
        this.SelectedItem = ItemsSource[SelectedIndex];
    }


    private static void OnSelectedItemChanged(BindableObject bindable, object oldValue, object newValue)
    {
        BindablePicker picker = (BindablePicker)bindable;
        picker.SelectedItem = newValue;
        if (picker.ItemsSource != null && picker.SelectedItem != null)
        {
            int count = 0;
            foreach (object obj in picker.ItemsSource)
            {
                if (obj == picker.SelectedItem)
                {
                    picker.SelectedIndex = count;
                    break;
                }
                count++;
            }
        }
    }

    private static void OnDisplayPropertyChanged(BindableObject bindable, object oldValue, object newValue)
    {
        BindablePicker picker = (BindablePicker)bindable;
        picker.DisplayProperty = (string)newValue;
        loadItemsAndSetSelected(bindable);

    }
    private static void OnItemsSourceChanged(BindableObject bindable, object oldValue, object newValue)
    {
        var picker = (BindablePicker)bindable;
        picker.ItemsSource = (IList)newValue;

        var oc = newValue as INotifyCollectionChanged;

        if (oc != null && !PickerLookup.ContainsKey(oc))
        {
            oc.CollectionChanged += Oc_CollectionChanged;
            PickerLookup.Add(oc, new WeakReference(picker));
        }

        loadItemsAndSetSelected(bindable);
    }

    private static readonly Dictionary<INotifyCollectionChanged, WeakReference> PickerLookup = new Dictionary<INotifyCollectionChanged, WeakReference>();

    private static void Oc_CollectionChanged(object sender, NotifyCollectionChangedEventArgs e)
    {
        var oc = (INotifyCollectionChanged)sender;

        if (e.Action == NotifyCollectionChangedAction.Add)
        {
            var picker = (BindablePicker)PickerLookup[oc].Target;

            foreach (var newItem in e.NewItems)
            {
                var value = string.Empty;
                if (picker.DisplayProperty != null)
                {
                    var prop = newItem.GetType().GetRuntimeProperties().FirstOrDefault(p => string.Equals(p.Name, picker.DisplayProperty, StringComparison.OrdinalIgnoreCase));

                    if (prop != null)
                        value = prop.GetValue(newItem).ToString();
                }
                else
                {
                    value = newItem.ToString();
                }

                picker.Items.Add(value);
            }
        }
        else if (e.Action == NotifyCollectionChangedAction.Remove)
        {
            var picker = (BindablePicker)PickerLookup[oc].Target;

            foreach (var newItem in e.OldItems)
            {
                var value = string.Empty;
                if (picker.DisplayProperty != null)
                {
                    var prop = newItem.GetType().GetRuntimeProperties().FirstOrDefault(p => string.Equals(p.Name, picker.DisplayProperty, StringComparison.OrdinalIgnoreCase));

                    if (prop != null)
                        value = prop.GetValue(newItem).ToString();
                }
                else
                {
                    value = newItem.ToString();
                }

                picker.Items.Remove(value);
            }
        }
    }

    static void loadItemsAndSetSelected(BindableObject bindable)
    {

        BindablePicker picker = (BindablePicker)bindable;
        if (picker.ItemsSource as IEnumerable != null)
        {
            int count = 0;
            foreach (object obj in (IEnumerable)picker.ItemsSource)
            {
                string value = string.Empty;
                if (picker.DisplayProperty != null)
                {
                    var prop = obj.GetType().GetRuntimeProperties().FirstOrDefault(p => string.Equals(p.Name, picker.DisplayProperty, StringComparison.OrdinalIgnoreCase));
                    if (prop != null)
                    {
                        value = prop.GetValue(obj).ToString();
                    }
                }
                else
                {
                    value = obj.ToString();
                }
                picker.Items.Add(value);
                if (picker.SelectedItem != null)
                {
                    if (picker.SelectedItem == obj)
                    {
                        picker.SelectedIndex = count;
                    }
                }
                count++;
            }
        }
    }
}

BindablePicker:

    List<PictureModel> _pages;
    public List<PictureModel> Pages
    {
        get
        {
            return _pages;
        }
        set
        {
            _pages = value;
            RaisePropertyChanged(() => Pages);
            CurrentPage = Pages.FirstOrDefault();
        }
    }

    private AttributeValue _selectedAttributeValue;

    public AttributeValue SelectedAttributeValue
    {
        get { return _selectedAttributeValue; }
        set
        {
            _selectedAttributeValue = value;
            RaisePropertyChanged(() => SelectedAttributeValue);
            SelectedAttributeCommand.Execute(null);

        }
    }

    public ICommand SelectedAttributeCommand
    {
        get
        {
            //return new MvxCommand(() => ShowViewModel<ReviewsPageViewModel>());
            return new MvxCommand(() =>
            {
                ChangePresentation(new MvxClosePresentationHint(new ProductListPageViewModel()));
            });

        }
    }

<controls:AwesomeWrappanel HorizontalOptions="CenterAndExpand"        Orientation="Horizontal" ItemsSource="{Binding ProductDeatil.ProductAttributes}" Spacing="10">
        <controls:AwesomeWrappanel.ItemTemplate>
                <DataTemplate>
                       <controls:BindablePicker ItemsSource="{Binding Values}" 
                         DisplayProperty="Name" Title="{Binding Name}" 
                         SelectedIndex="0" SelectedItem="{Binding 
                         SelectedAttributeValue, Mode=TwoWay}" />           
               </DataTemplate>
        </controls:AwesomeWrappanel.ItemTemplate>
</controls:AwesomeWrappanel>

public class BindablePicker : Picker
{
    public BindablePicker()
    {
        this.SelectedIndexChanged += OnSelectedIndexChanged;
    }


    public static readonly BindableProperty SelectedItemProperty = BindableProperty.Create("SelectedItem", typeof(object), typeof(BindablePicker), null, BindingMode.TwoWay, null, new BindableProperty.BindingPropertyChangedDelegate(BindablePicker.OnSelectedItemChanged), null, null, null);
    public static readonly BindableProperty ItemsSourceProperty = BindableProperty.Create("ItemsSource", typeof(IEnumerable), typeof(BindablePicker), null, BindingMode.TwoWay, null, new BindableProperty.BindingPropertyChangedDelegate(BindablePicker.OnItemsSourceChanged), null, null, null);
    public static readonly BindableProperty DisplayPropertyProperty = BindableProperty.Create("DisplayProperty", typeof(string), typeof(BindablePicker), null, BindingMode.TwoWay, null, new BindableProperty.BindingPropertyChangedDelegate(BindablePicker.OnDisplayPropertyChanged), null, null, null);

    public IList ItemsSource
    {
        get { return (IList)base.GetValue(BindablePicker.ItemsSourceProperty); }
        set { base.SetValue(BindablePicker.ItemsSourceProperty, value); }
    }

    public object SelectedItem
    {
        get { return base.GetValue(BindablePicker.SelectedItemProperty); }
        set
        {
            base.SetValue(BindablePicker.SelectedItemProperty, value);
            if (ItemsSource.Contains(SelectedItem))
            {
                SelectedIndex = ItemsSource.IndexOf(SelectedItem);
            }
            else
            {
                SelectedIndex = -1;
            }
        }
    }

    public string DisplayProperty
    {
        get { return (string)base.GetValue(BindablePicker.DisplayPropertyProperty); }
        set { base.SetValue(BindablePicker.DisplayPropertyProperty, value); }
    }

    private void OnSelectedIndexChanged(object sender, EventArgs e)
    {
        this.SelectedItem = ItemsSource[SelectedIndex];
    }


    private static void OnSelectedItemChanged(BindableObject bindable, object oldValue, object newValue)
    {
        BindablePicker picker = (BindablePicker)bindable;
        picker.SelectedItem = newValue;
        if (picker.ItemsSource != null && picker.SelectedItem != null)
        {
            int count = 0;
            foreach (object obj in picker.ItemsSource)
            {
                if (obj == picker.SelectedItem)
                {
                    picker.SelectedIndex = count;
                    break;
                }
                count++;
            }
        }
    }

    private static void OnDisplayPropertyChanged(BindableObject bindable, object oldValue, object newValue)
    {
        BindablePicker picker = (BindablePicker)bindable;
        picker.DisplayProperty = (string)newValue;
        loadItemsAndSetSelected(bindable);

    }
    private static void OnItemsSourceChanged(BindableObject bindable, object oldValue, object newValue)
    {
        var picker = (BindablePicker)bindable;
        picker.ItemsSource = (IList)newValue;

        var oc = newValue as INotifyCollectionChanged;

        if (oc != null && !PickerLookup.ContainsKey(oc))
        {
            oc.CollectionChanged += Oc_CollectionChanged;
            PickerLookup.Add(oc, new WeakReference(picker));
        }

        loadItemsAndSetSelected(bindable);
    }

    private static readonly Dictionary<INotifyCollectionChanged, WeakReference> PickerLookup = new Dictionary<INotifyCollectionChanged, WeakReference>();

    private static void Oc_CollectionChanged(object sender, NotifyCollectionChangedEventArgs e)
    {
        var oc = (INotifyCollectionChanged)sender;

        if (e.Action == NotifyCollectionChangedAction.Add)
        {
            var picker = (BindablePicker)PickerLookup[oc].Target;

            foreach (var newItem in e.NewItems)
            {
                var value = string.Empty;
                if (picker.DisplayProperty != null)
                {
                    var prop = newItem.GetType().GetRuntimeProperties().FirstOrDefault(p => string.Equals(p.Name, picker.DisplayProperty, StringComparison.OrdinalIgnoreCase));

                    if (prop != null)
                        value = prop.GetValue(newItem).ToString();
                }
                else
                {
                    value = newItem.ToString();
                }

                picker.Items.Add(value);
            }
        }
        else if (e.Action == NotifyCollectionChangedAction.Remove)
        {
            var picker = (BindablePicker)PickerLookup[oc].Target;

            foreach (var newItem in e.OldItems)
            {
                var value = string.Empty;
                if (picker.DisplayProperty != null)
                {
                    var prop = newItem.GetType().GetRuntimeProperties().FirstOrDefault(p => string.Equals(p.Name, picker.DisplayProperty, StringComparison.OrdinalIgnoreCase));

                    if (prop != null)
                        value = prop.GetValue(newItem).ToString();
                }
                else
                {
                    value = newItem.ToString();
                }

                picker.Items.Remove(value);
            }
        }
    }

    static void loadItemsAndSetSelected(BindableObject bindable)
    {

        BindablePicker picker = (BindablePicker)bindable;
        if (picker.ItemsSource as IEnumerable != null)
        {
            int count = 0;
            foreach (object obj in (IEnumerable)picker.ItemsSource)
            {
                string value = string.Empty;
                if (picker.DisplayProperty != null)
                {
                    var prop = obj.GetType().GetRuntimeProperties().FirstOrDefault(p => string.Equals(p.Name, picker.DisplayProperty, StringComparison.OrdinalIgnoreCase));
                    if (prop != null)
                    {
                        value = prop.GetValue(obj).ToString();
                    }
                }
                else
                {
                    value = obj.ToString();
                }
                picker.Items.Add(value);
                if (picker.SelectedItem != null)
                {
                    if (picker.SelectedItem == obj)
                    {
                        picker.SelectedIndex = count;
                    }
                }
                count++;
            }
        }
    }
}

公共类BindablePicker:Picker
{
公共BindablePicker（）
{
this.SelectedIndexChanged+=on SelectedIndexChanged；
}
public static readonly BindableProperty SelectedItemProperty=BindableProperty.Create（“SelectedItem”、typeof（object）、typeof（BindablePicker）、null、BindingMode.TwoWay、null、new BindableProperty.BindablePicker.OnSelectedItemChanged）、null、null；
public static readonly BindableProperty ItemsSourceProperty=BindableProperty.Create（“ItemsSource”，typeof（IEnumerable），typeof（BindablePicker），null，BindingMode.TwoWay，null，new BindableProperty.bindingPropertyChangedElegate（BindablePicker.onitemsourcechanged），null，null）；
public static readonly BindableProperty DisplayProperty=BindableProperty.Create（“DisplayProperty”、typeof（string）、typeof（BindablePicker）、null、BindingMode.TwoWay、null、new BindableProperty.bindablepichangedelegate（BindablePicker.OnDisplayPropertyChanged）、null、null；
公共IList项目资源
{
获取{return（IList）base.GetValue（BindablePicker.ItemsSourceProperty）；}
set{base.SetValue（BindablePicker.ItemsSourceProperty，value）；}
}
公共对象SelectedItem
{
获取{return base.GetValue（BindablePicker.SelectedItemProperty）；}
设置
{
base.SetValue（BindablePicker.SelectedItemProperty，值）；
if（ItemsSource.Contains（SelectedItem））
{
SelectedIndex=ItemsSource.IndexOf（SelectedItem）；
}
其他的
{
SelectedIndex=-1；
}
}
}
公共字符串显示属性
{
get{return（string）base.GetValue（BindablePicker.DisplayPropertyProperty）；}
set{base.SetValue（BindablePicker.DisplayPropertyProperty，value）；}
}
SelectedIndexChanged上的私有无效（对象发送方，事件参数e）
{
this.SelectedItem=ItemsSource[SelectedIndex]；
}
SelectedItemChanged上的私有静态无效（BindableObject bindable、object oldValue、object newValue）
{
BindablePicker-picker=（BindablePicker）bindable；
picker.SelectedItem=newValue；
if（picker.ItemsSource！=null&&picker.SelectedItem！=null）
{
整数计数=0；
foreach（picker.ItemsSource中的对象obj）
{
if（obj==picker.SelectedItem）
{
picker.SelectedIndex=计数；
打破
}
计数++；
}
}
}
私有静态void OnDisplayPropertyChanged（BindableObject bindable、object oldValue、object newValue）
{
BindablePicker-picker=（BindablePicker）bindable；
picker.DisplayProperty=（字符串）newValue；
LoadItems和SetSelected（可绑定）；
}
私有静态资源已更改（BindableObject bindable、object oldValue、object newValue）
{
var picker=（BindablePicker）bindable；
picker.ItemsSource=（IList）newValue；
var oc=INotifyCollectionChanged时的新值；
if（oc！=null&&！PickerLookup.ContainsKey（oc））
{
oc.CollectionChanged+=oc_CollectionChanged；
PickerLookup.Add（oc，新WeakReference（picker））；
}
LoadItems和SetSelected（可绑定）；
}
私有静态只读字典PickerLookup=new Dictionary（）；
私有静态无效Oc_CollectionChanged（对象发送方，NotifyCollectionChangedEventArgs e）
{
var oc=（INotifyCollectionChanged）发送方；
if（e.Action==NotifyCollectionChangedAction.Add）
{
var picker=（BindablePicker）PickerLookup[oc].Target；
foreach（e.NewItems中的var newItem）
{
var值=string.Empty；
if（picker.DisplayProperty！=null）
{
var prop=newItem.GetType（）.GetRuntimeProperties（）.FirstOrDefault（p=>string.Equals（p.Name，picker.DisplayProperty，StringComparison.OrdinalIgnoreCase））；
如果（prop！=null）
value=prop.GetValue（newItem）.ToString（）；
}
其他的
{
value=newItem.ToString（）；
}
选择器。项目。添加（值）；
}
}
else if（e.Action==NotifyCollectionChangedAction.Remove）
{
var picker=（BindablePicker）PickerLookup[oc].Target；
foreach（e.OldItems中的var newItem）
{
var值=string.Empty；
if（picker.DisplayProperty！=null）
{