Ndef Class

Reference

Definition

Namespace:: Android.Nfc.Tech

Assembly:: Mono.Android.dll

Important

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Provides access to NDEF content and operations on a Tag.

[Android.Runtime.Register("android/nfc/tech/Ndef", DoNotGenerateAcw=true)]
public sealed class Ndef : Android.Nfc.Tech.BasicTagTechnology, IDisposable, Java.Interop.IJavaPeerable

[<Android.Runtime.Register("android/nfc/tech/Ndef", DoNotGenerateAcw=true)>]
type Ndef = class
    inherit BasicTagTechnology
    interface ITagTechnology
    interface ICloseable
    interface IJavaObject
    interface IDisposable
    interface IJavaPeerable

Inheritance: Object

Object

BasicTagTechnology
Ndef

Attributes: RegisterAttribute

Implements: ITagTechnology IJavaObject IJavaPeerable ICloseable IDisposable

Remarks

Provides access to NDEF content and operations on a Tag.

Acquire a Ndef object using #get.

NDEF is an NFC Forum data format. The data formats are implemented in android.nfc.NdefMessage and android.nfc.NdefRecord. This class provides methods to retrieve and modify the android.nfc.NdefMessage on a tag.

There are currently four NFC Forum standardized tag types that can be formatted to contain NDEF data. <ul> <li>NFC Forum Type 1 Tag (#NFC_FORUM_TYPE_1), such as the Innovision Topaz <li>NFC Forum Type 2 Tag (#NFC_FORUM_TYPE_2), such as the NXP MIFARE Ultralight <li>NFC Forum Type 3 Tag (#NFC_FORUM_TYPE_3), such as Sony Felica <li>NFC Forum Type 4 Tag (#NFC_FORUM_TYPE_4), such as NXP MIFARE Desfire </ul> It is mandatory for all Android devices with NFC to correctly enumerate Ndef on NFC Forum Tag Types 1-4, and implement all NDEF operations as defined in this class.

Some vendors have their own well defined specifications for storing NDEF data on tags that do not fall into the above categories. Android devices with NFC should enumerate and implement Ndef under these vendor specifications where possible, but it is not mandatory. #getType returns a String describing this specification, for example #MIFARE_CLASSIC is com.nxp.ndef.mifareclassic.

Android devices that support MIFARE Classic must also correctly implement Ndef on MIFARE Classic tags formatted to NDEF.

For guaranteed compatibility across all Android devices with NFC, it is recommended to use NFC Forum Types 1-4 in new deployments of NFC tags with NDEF payload. Vendor NDEF formats will not work on all Android devices.

<p class="note"><strong>Note:</strong> Methods that perform I/O operations require the android.Manifest.permission#NFC permission.

Java documentation for android.nfc.tech.Ndef.

Portions of this page are modifications based on work created and shared by the Android Open Source Project and used according to terms described in the Creative Commons 2.5 Attribution License.

Fields

MifareClassic	NDEF on MIFARE Classic
NfcForumType1	NFC Forum Tag Type 1
NfcForumType2	NFC Forum Tag Type 2
NfcForumType3	NFC Forum Tag Type 3
NfcForumType4	NFC Forum Tag Type 4

Properties

CachedNdefMessage	Get the `NdefMessage` that was read from the tag at discovery time.
Class	Returns the runtime class of this `Object`. (Inherited from Object)
Handle	The handle to the underlying Android instance. (Inherited from Object)
IsConnected	Helper to indicate if I/O operations should be possible.
IsWritable	Determine if the tag is writable.
JniIdentityHashCode	(Inherited from Object)
JniPeerMembers
MaxSize	Get the maximum NDEF message size in bytes.
NdefMessage	Read the current `android.nfc.NdefMessage` on this tag.
PeerReference	(Inherited from Object)
Tag	Get the Tag object backing this ITagTechnology object.
ThresholdClass	(Inherited from BasicTagTechnology)
ThresholdType	(Inherited from BasicTagTechnology)
Type	Get the NDEF tag type.

Methods

CanMakeReadOnly()	Indicates whether a tag can be made read-only with `#makeReadOnly()`.
Clone()	Creates and returns a copy of this object. (Inherited from Object)
Close()	Disable I/O operations to the tag from this ITagTechnology object, and release resources.
Connect()	Enable I/O operations to the tag from this ITagTechnology object.
Dispose()	(Inherited from Object)
Dispose(Boolean)	(Inherited from Object)
Equals(Object)	Indicates whether some other object is "equal to" this one. (Inherited from Object)
Get(Tag)	Get an instance of `Ndef` for the given tag.
GetHashCode()	Returns a hash code value for the object. (Inherited from Object)
JavaFinalize()	Called by the garbage collector on an object when garbage collection determines that there are no more references to the object. (Inherited from Object)
MakeReadOnly()	Make a tag read-only.
MakeReadOnlyAsync()
Notify()	Wakes up a single thread that is waiting on this object's monitor. (Inherited from Object)
NotifyAll()	Wakes up all threads that are waiting on this object's monitor. (Inherited from Object)
SetHandle(IntPtr, JniHandleOwnership)	Sets the Handle property. (Inherited from Object)
ToArray<T>()	(Inherited from Object)
ToString()	Returns a string representation of the object. (Inherited from Object)
UnregisterFromRuntime()	(Inherited from Object)
Wait()	Causes the current thread to wait until it is awakened, typically by being <em>notified</em> or <em>interrupted</em>. (Inherited from Object)
Wait(Int64, Int32)	Causes the current thread to wait until it is awakened, typically by being <em>notified</em> or <em>interrupted</em>, or until a certain amount of real time has elapsed. (Inherited from Object)
Wait(Int64)	Causes the current thread to wait until it is awakened, typically by being <em>notified</em> or <em>interrupted</em>, or until a certain amount of real time has elapsed. (Inherited from Object)
WriteNdefMessage(NdefMessage)	Overwrite the `NdefMessage` on this tag.
WriteNdefMessageAsync(NdefMessage)

Explicit Interface Implementations

IJavaPeerable.Disposed()	(Inherited from Object)
IJavaPeerable.DisposeUnlessReferenced()	(Inherited from Object)
IJavaPeerable.Finalized()	(Inherited from Object)
IJavaPeerable.JniManagedPeerState	(Inherited from Object)
IJavaPeerable.SetJniIdentityHashCode(Int32)	(Inherited from Object)
IJavaPeerable.SetJniManagedPeerState(JniManagedPeerStates)	(Inherited from Object)
IJavaPeerable.SetPeerReference(JniObjectReference)	(Inherited from Object)

Extension Methods

ConnectAsync(ITagTechnology)
JavaCast<TResult>(IJavaObject)	Performs an Android runtime-checked type conversion.
JavaCast<TResult>(IJavaObject)
GetJniTypeName(IJavaPeerable)

Applies to

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