ObservableCollection<(Of <(T>)>) Class
[ This article is for Windows Phone 8 developers. If you’re developing for Windows 10, see the latest documentation. ]
Represents a dynamic data collection that provides notifications when items get added, removed, or when the entire list is refreshed.
Inheritance Hierarchy
System..::.Object
System.Collections.ObjectModel..::.Collection<(Of <(T>)>)
System.Collections.ObjectModel..::.ObservableCollection<(Of <(T>)>)
Microsoft.Phone.Maps.Controls..::.GeoCoordinateCollection
Microsoft.Phone.Maps.Controls..::.MapLayer
Namespace: System.Collections.ObjectModel
Assembly: System (in System.dll)
Syntax
Public Class ObservableCollection(Of T) _
Inherits Collection(Of T) _
Implements INotifyCollectionChanged, INotifyPropertyChanged
public class ObservableCollection<T> : Collection<T>,
INotifyCollectionChanged, INotifyPropertyChanged
Type Parameters
- T
The type of items in the collection.
The ObservableCollection<(Of <(T>)>) type exposes the following members.
Constructors
| Name | Description | |
|---|---|---|
.gif "Public method") |
ObservableCollection<(Of <(T>)>)()()() | Initializes a new, empty instance of the ObservableCollection<(Of <(T>)>) class. |
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ObservableCollection<(Of <(T>)>)(IEnumerable<(Of <(T>)>)) | Initializes a new instance of the ObservableCollection<(Of <(T>)>) class and populates it with items copied from the specified collection. |
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ObservableCollection<(Of <(T>)>)(List<(Of <(T>)>)) | Initializes a new instance of the ObservableCollection<(Of <(T>)>) class and populates it with items copied from the specified list. |
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Properties
| Name | Description | |
|---|---|---|
.gif "Public property") |
Count | Gets the number of elements actually contained in the Collection<(Of <(T>)>). (Inherited from Collection<(Of <(T>)>).) |
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Item | Gets or sets the element at the specified index. (Inherited from Collection<(Of <(T>)>).) |
.gif "Protected property") |
Items | Gets a IList<(Of <(T>)>) wrapper around the Collection<(Of <(T>)>). (Inherited from Collection<(Of <(T>)>).) |
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Methods
| Name | Description | |
|---|---|---|
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Add | Adds an object to the end of the Collection<(Of <(T>)>). (Inherited from Collection<(Of <(T>)>).) |
.gif "Protected method") |
BlockReentrancy | Disallows reentrant attempts to change this collection. |
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CheckReentrancy | Checks for reentrant attempts to change this collection. |
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Clear | Removes all elements from the Collection<(Of <(T>)>). (Inherited from Collection<(Of <(T>)>).) |
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ClearItems | Removes all items from the collection. (Overrides Collection<(Of <(T>)>)..::.ClearItems()()().) |
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Contains | Determines whether an element is in the Collection<(Of <(T>)>). (Inherited from Collection<(Of <(T>)>).) |
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CopyTo | Copies the entire Collection<(Of <(T>)>) to a compatible one-dimensional Array, starting at the specified index of the target array. (Inherited from Collection<(Of <(T>)>).) |
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Equals(Object) | Determines whether the specified Object is equal to the current Object. (Inherited from Object.) |
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Finalize | Allows an object to try to free resources and perform other cleanup operations before the Object is reclaimed by garbage collection. (Inherited from Object.) |
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GetEnumerator | Returns an enumerator that iterates through the Collection<(Of <(T>)>). (Inherited from Collection<(Of <(T>)>).) |
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GetHashCode | Serves as a hash function for a particular type. (Inherited from Object.) |
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GetType | Gets the Type of the current instance. (Inherited from Object.) |
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IndexOf | Searches for the specified object and returns the zero-based index of the first occurrence within the entire Collection<(Of <(T>)>). (Inherited from Collection<(Of <(T>)>).) |
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Insert | Inserts an element into the Collection<(Of <(T>)>) at the specified index. (Inherited from Collection<(Of <(T>)>).) |
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InsertItem | Inserts an item into the collection at the specified index. (Overrides Collection<(Of <(T>)>)..::.InsertItem(Int32, T).) |
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MemberwiseClone | Creates a shallow copy of the current Object. (Inherited from Object.) |
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Move | Moves the item at the specified index to a new location in the collection. |
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MoveItem | Moves the item at the specified index to a new location in the collection. |
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OnCollectionChanged | Raises the CollectionChanged event with the provided event data. |
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OnPropertyChanged | Raises the PropertyChanged event with the provided arguments. |
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Remove | Removes the first occurrence of a specific object from the Collection<(Of <(T>)>). (Inherited from Collection<(Of <(T>)>).) |
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RemoveAt | Removes the element at the specified index of the Collection<(Of <(T>)>). (Inherited from Collection<(Of <(T>)>).) |
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RemoveItem | Removes the item at the specified index from the collection. (Overrides Collection<(Of <(T>)>)..::.RemoveItem(Int32).) |
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SetItem | Replaces the item at the specified index. (Overrides Collection<(Of <(T>)>)..::.SetItem(Int32, T).) |
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ToString | Returns a string that represents the current object. (Inherited from Object.) |
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Events
| Name | Description | |
|---|---|---|
.gif "Public event") |
CollectionChanged | Occurs when an item in the collection changes, or the entire collection changes. |
.gif "Protected event") |
PropertyChanged | Occurs when a property on an individual item in the collection changes. |
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Explicit Interface Implementations
| Name | Description | |
|---|---|---|
.gif "Explicit interface implemetation") .gif "Private method") |
ICollection..::.CopyTo | Copies the elements of the ICollection to an Array, starting at a particular Array index. (Inherited from Collection<(Of <(T>)>).) |
.gif "Private property") |
ICollection<(Of <(T>)>)..::.IsReadOnly | Gets a value indicating whether the ICollection<(Of <(T>)>) is read-only. (Inherited from Collection<(Of <(T>)>).) |
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ICollection..::.IsSynchronized | Gets a value indicating whether access to the ICollection is synchronized (thread safe). (Inherited from Collection<(Of <(T>)>).) |
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ICollection..::.SyncRoot | Gets an object that can be used to synchronize access to the ICollection. (Inherited from Collection<(Of <(T>)>).) |
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IEnumerable..::.GetEnumerator | Returns an enumerator that iterates through a collection. (Inherited from Collection<(Of <(T>)>).) |
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IList..::.Add | Adds an item to the IList. (Inherited from Collection<(Of <(T>)>).) |
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IList..::.Contains | Determines whether the IList contains a specific value. (Inherited from Collection<(Of <(T>)>).) |
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IList..::.IndexOf | Determines the index of a specific item in the IList. (Inherited from Collection<(Of <(T>)>).) |
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IList..::.Insert | Inserts an item into the IList at the specified index. (Inherited from Collection<(Of <(T>)>).) |
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IList..::.IsFixedSize | Gets a value indicating whether the IList has a fixed size. (Inherited from Collection<(Of <(T>)>).) |
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IList..::.IsReadOnly | Gets a value indicating whether the IList is read-only. (Inherited from Collection<(Of <(T>)>).) |
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IList..::.Item | Gets or sets the element at the specified index. (Inherited from Collection<(Of <(T>)>).) |
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IList..::.Remove | Removes the first occurrence of a specific object from the IList. (Inherited from Collection<(Of <(T>)>).) |
.gif "Private event") |
INotifyPropertyChanged..::.PropertyChanged | Occurs when a property value changes. |
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Remarks
You can enumerate over any collection that implements the IEnumerable interface, and this is sufficient for one-time data binding in XAML. However, to set up dynamic bindings so that insertions or deletions in the collection can update the UI automatically, the collection must implement the INotifyCollectionChanged interface. This interface exposes the CollectionChanged event, an event that should be raised whenever the underlying collection changes.
XAML provides the ObservableCollection<(Of <(T>)>) class, which is a base class data collection that implements the INotifyCollectionChanged interface, as well as the INotifyPropertyChanged interface. It also has the expected collection support, defined by deriving from the Collection<(Of <(T>)>) class.
Version Information
Windows Phone OS
Supported in: 8.1, 8.0, 7.1, 7.0
Platforms
Windows Phone
Thread Safety
Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.