path: root/docs/Xamarin.Forms.Core/Xamarin.Forms/Picker.xml

<Type Name="Picker" FullName="Xamarin.Forms.Picker">
  <TypeSignature Language="C#" Value="public class Picker : Xamarin.Forms.View" />
  <TypeSignature Language="ILAsm" Value=".class public auto ansi beforefieldinit Picker extends Xamarin.Forms.View" />
  <AssemblyInfo>
    <AssemblyName>Xamarin.Forms.Core</AssemblyName>
    <AssemblyVersion>1.0.0.0</AssemblyVersion>
    <AssemblyVersion>1.1.0.0</AssemblyVersion>
    <AssemblyVersion>1.2.0.0</AssemblyVersion>
    <AssemblyVersion>1.3.0.0</AssemblyVersion>
    <AssemblyVersion>1.4.0.0</AssemblyVersion>
    <AssemblyVersion>1.5.0.0</AssemblyVersion>
    <AssemblyVersion>2.0.0.0</AssemblyVersion>
  </AssemblyInfo>
  <Base>
    <BaseTypeName>Xamarin.Forms.View</BaseTypeName>
  </Base>
  <Interfaces />
  <Attributes>
    <Attribute>
      <AttributeName>Xamarin.Forms.RenderWith(typeof(Xamarin.Forms.Platform._PickerRenderer))</AttributeName>
    </Attribute>
  </Attributes>
  <Docs>
    <summary>A <see cref="T:Xamarin.Forms.View" /> control for picking an element in a list.</summary>
    <remarks>
      <para>The visual representation of a Picker is similar to a <see cref="T:Xamarin.Forms.Entry" />, but a picker control appears in place of a keyboard.</para>
      <para>The following example shows the creation of a Picker.</para>
      <example>
        <code lang="C#"><![CDATA[using System;
using System.Collections.Generic;
using Xamarin.Forms;

namespace FormsGallery
{
    class PickerDemoPage : ContentPage
    {
        // Dictionary to get Color from color name.
        Dictionary<string, Color> nameToColor = new Dictionary<string, Color>
        {
            { "Aqua", Color.Aqua }, { "Black", Color.Black },
            { "Blue", Color.Blue }, { "Fuschia", Color.Fuschia },
            { "Gray", Color.Gray }, { "Green", Color.Green },
            { "Lime", Color.Lime }, { "Maroon", Color.Maroon },
            { "Navy", Color.Navy }, { "Olive", Color.Olive },
            { "Purple", Color.Purple }, { "Red", Color.Red },
            { "Silver", Color.Silver }, { "Teal", Color.Teal },
            { "White", Color.White }, { "Yellow", Color.Yellow }
        };

        public PickerDemoPage()
        {
            Label header = new Label
            {
                Text = "Picker",
                FontSize = Device.GetNamedSize (NamedSize.Large, typeof(Label)),
                HorizontalOptions = LayoutOptions.Center
            };

            Picker picker = new Picker
            {
                Title = "Color",
                VerticalOptions = LayoutOptions.CenterAndExpand
            };

            foreach (string colorName in nameToColor.Keys)
            {
                picker.Items.Add(colorName);
            }

            // Create BoxView for displaying picked Color
            BoxView boxView = new BoxView
            {
                WidthRequest = 150,
                HeightRequest = 150,
                HorizontalOptions = LayoutOptions.Center,
                VerticalOptions = LayoutOptions.CenterAndExpand
            };

            picker.SelectedIndexChanged += (sender, args) =>
                {
                    if (picker.SelectedIndex == -1)
                    {
                        boxView.Color = Color.Default;
                    }
                    else
                    {
                        string colorName = picker.Items[picker.SelectedIndex];
                        boxView.Color = nameToColor[colorName];
                    }
                };

            // Accomodate iPhone status bar.
            this.Padding = new Thickness(10, Device.OnPlatform(20, 0, 0), 10, 5);

            // Build the page.
            this.Content = new StackLayout
            {
                Children =
                {
                    header,
                    picker,
                    boxView
                }
            };

        }
    }
}
]]></code>
      </example>
      <para>XAML for Xamarin.Forms supports the following properties for the <see cref="T:Xamarin.Forms.Picker" /> class:</para>
      <list type="table">
        <listheader>
          <term>Property</term>
          <description>Value</description>
        </listheader>
        <item>
          <term>Items</term>
          <description>
            <para>A local file specification that identifies an image.</para>
          </description>
        </item>
        <item>
          <term>SelectedIndex</term>
          <description>
            <para>An integer, from 0 to 1 less than the count of items that are listed in <c>Items</c>. Currently, this element must be specified in a tag that appears lexically below <c>Items</c>.</para>
          </description>
        </item>
        <item>
          <term>Title</term>
          <description>
            <para>Text that represents the title of the picker.</para>
          </description>
        </item>
      </list>
      <para>
        <img href="Picker.TripleScreenShot.png" />
      </para>
    </remarks>
  </Docs>
  <Members>
    <Member MemberName=".ctor">
      <MemberSignature Language="C#" Value="public Picker ();" />
      <MemberSignature Language="ILAsm" Value=".method public hidebysig specialname rtspecialname instance void .ctor() cil managed" />
      <MemberType>Constructor</MemberType>
      <AssemblyInfo>
        <AssemblyVersion>1.0.0.0</AssemblyVersion>
        <AssemblyVersion>1.1.0.0</AssemblyVersion>
        <AssemblyVersion>1.2.0.0</AssemblyVersion>
        <AssemblyVersion>1.3.0.0</AssemblyVersion>
        <AssemblyVersion>1.4.0.0</AssemblyVersion>
        <AssemblyVersion>1.5.0.0</AssemblyVersion>
        <AssemblyVersion>2.0.0.0</AssemblyVersion>
      </AssemblyInfo>
      <Parameters />
      <Docs>
        <summary>Initializes a new instance of the Picker class.</summary>
        <remarks>
        </remarks>
      </Docs>
    </Member>
    <Member MemberName="Items">
      <MemberSignature Language="C#" Value="public System.Collections.Generic.IList&lt;string&gt; Items { get; }" />
      <MemberSignature Language="ILAsm" Value=".property instance class System.Collections.Generic.IList`1&lt;string&gt; Items" />
      <MemberType>Property</MemberType>
      <AssemblyInfo>
        <AssemblyVersion>1.0.0.0</AssemblyVersion>
        <AssemblyVersion>1.1.0.0</AssemblyVersion>
        <AssemblyVersion>1.2.0.0</AssemblyVersion>
        <AssemblyVersion>1.3.0.0</AssemblyVersion>
        <AssemblyVersion>1.4.0.0</AssemblyVersion>
        <AssemblyVersion>1.5.0.0</AssemblyVersion>
        <AssemblyVersion>2.0.0.0</AssemblyVersion>
      </AssemblyInfo>
      <ReturnValue>
        <ReturnType>System.Collections.Generic.IList&lt;System.String&gt;</ReturnType>
      </ReturnValue>
      <Docs>
        <summary>Gets the list of choices.</summary>
        <value>An IList&lt;string&gt; representing the Picker choices.</value>
        <remarks>This property is read-only, but exposes the IList&lt;&gt; interface, so items can be added using Add().</remarks>
      </Docs>
    </Member>
    <Member MemberName="SelectedIndex">
      <MemberSignature Language="C#" Value="public int SelectedIndex { get; set; }" />
      <MemberSignature Language="ILAsm" Value=".property instance int32 SelectedIndex" />
      <MemberType>Property</MemberType>
      <AssemblyInfo>
        <AssemblyVersion>1.0.0.0</AssemblyVersion>
        <AssemblyVersion>1.1.0.0</AssemblyVersion>
        <AssemblyVersion>1.2.0.0</AssemblyVersion>
        <AssemblyVersion>1.3.0.0</AssemblyVersion>
        <AssemblyVersion>1.4.0.0</AssemblyVersion>
        <AssemblyVersion>1.5.0.0</AssemblyVersion>
        <AssemblyVersion>2.0.0.0</AssemblyVersion>
      </AssemblyInfo>
      <ReturnValue>
        <ReturnType>System.Int32</ReturnType>
      </ReturnValue>
      <Docs>
        <summary>Gets or sets the index of the slected item of the picker. This is a bindable property.</summary>
        <value>An 0-based index representing the selected item in the list. Default is -1.</value>
        <remarks>A value of -1 represents no item selected.</remarks>
      </Docs>
    </Member>
    <Member MemberName="SelectedIndexChanged">
      <MemberSignature Language="C#" Value="public event EventHandler SelectedIndexChanged;" />
      <MemberSignature Language="ILAsm" Value=".event class System.EventHandler SelectedIndexChanged" />
      <MemberType>Event</MemberType>
      <AssemblyInfo>
        <AssemblyVersion>1.0.0.0</AssemblyVersion>
        <AssemblyVersion>1.1.0.0</AssemblyVersion>
        <AssemblyVersion>1.2.0.0</AssemblyVersion>
        <AssemblyVersion>1.3.0.0</AssemblyVersion>
        <AssemblyVersion>1.4.0.0</AssemblyVersion>
        <AssemblyVersion>1.5.0.0</AssemblyVersion>
        <AssemblyVersion>2.0.0.0</AssemblyVersion>
      </AssemblyInfo>
      <ReturnValue>
        <ReturnType>System.EventHandler</ReturnType>
      </ReturnValue>
      <Docs>
        <summary>Raised when the value of the SelectIndex property has changed.</summary>
        <remarks>To be added.</remarks>
      </Docs>
    </Member>
    <Member MemberName="SelectedIndexProperty">
      <MemberSignature Language="C#" Value="public static readonly Xamarin.Forms.BindableProperty SelectedIndexProperty;" />
      <MemberSignature Language="ILAsm" Value=".field public static initonly class Xamarin.Forms.BindableProperty SelectedIndexProperty" />
      <MemberType>Field</MemberType>
      <AssemblyInfo>
        <AssemblyVersion>1.0.0.0</AssemblyVersion>
        <AssemblyVersion>1.1.0.0</AssemblyVersion>
        <AssemblyVersion>1.2.0.0</AssemblyVersion>
        <AssemblyVersion>1.3.0.0</AssemblyVersion>
        <AssemblyVersion>1.4.0.0</AssemblyVersion>
        <AssemblyVersion>1.5.0.0</AssemblyVersion>
        <AssemblyVersion>2.0.0.0</AssemblyVersion>
      </AssemblyInfo>
      <ReturnValue>
        <ReturnType>Xamarin.Forms.BindableProperty</ReturnType>
      </ReturnValue>
      <Docs>
        <summary>Identifies the SelectedIndex bindable property.</summary>
        <remarks>
        </remarks>
      </Docs>
    </Member>
    <Member MemberName="Title">
      <MemberSignature Language="C#" Value="public string Title { get; set; }" />
      <MemberSignature Language="ILAsm" Value=".property instance string Title" />
      <MemberType>Property</MemberType>
      <AssemblyInfo>
        <AssemblyVersion>1.0.0.0</AssemblyVersion>
        <AssemblyVersion>1.1.0.0</AssemblyVersion>
        <AssemblyVersion>1.2.0.0</AssemblyVersion>
        <AssemblyVersion>1.3.0.0</AssemblyVersion>
        <AssemblyVersion>1.4.0.0</AssemblyVersion>
        <AssemblyVersion>1.5.0.0</AssemblyVersion>
        <AssemblyVersion>2.0.0.0</AssemblyVersion>
      </AssemblyInfo>
      <ReturnValue>
        <ReturnType>System.String</ReturnType>
      </ReturnValue>
      <Docs>
        <summary>Gets or sets the title for the Picker. This is a bindable property.</summary>
        <value>A string.</value>
        <remarks>Depending on the platform, the Title is shown as a placeholder, headline, or not showed at all.</remarks>
      </Docs>
    </Member>
    <Member MemberName="TitleProperty">
      <MemberSignature Language="C#" Value="public static readonly Xamarin.Forms.BindableProperty TitleProperty;" />
      <MemberSignature Language="ILAsm" Value=".field public static initonly class Xamarin.Forms.BindableProperty TitleProperty" />
      <MemberType>Field</MemberType>
      <AssemblyInfo>
        <AssemblyVersion>1.0.0.0</AssemblyVersion>
        <AssemblyVersion>1.1.0.0</AssemblyVersion>
        <AssemblyVersion>1.2.0.0</AssemblyVersion>
        <AssemblyVersion>1.3.0.0</AssemblyVersion>
        <AssemblyVersion>1.4.0.0</AssemblyVersion>
        <AssemblyVersion>1.5.0.0</AssemblyVersion>
        <AssemblyVersion>2.0.0.0</AssemblyVersion>
      </AssemblyInfo>
      <ReturnValue>
        <ReturnType>Xamarin.Forms.BindableProperty</ReturnType>
      </ReturnValue>
      <Docs>
        <summary>Identifies the Title bindable property.</summary>
        <remarks>
        </remarks>
      </Docs>
    </Member>
  </Members>
</Type>