VelocityTracker Class
Definition
Important
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Helper for tracking the velocity of motion events, for implementing flinging and other such gestures.
[Android.Runtime.Register("android/view/VelocityTracker", DoNotGenerateAcw=true)]
public sealed class VelocityTracker : Java.Lang.Object[<Android.Runtime.Register("android/view/VelocityTracker", DoNotGenerateAcw=true)>]
type VelocityTracker = class
inherit Object- Inheritance
- Attributes
Remarks
Helper for tracking the velocity of motion events, for implementing flinging and other such gestures.
Use #obtain to retrieve a new instance of the class when you are going to begin tracking. Put the motion events you receive into it with #addMovement(MotionEvent). When you want to determine the velocity, call #computeCurrentVelocity(int) and then call the velocity-getter methods like #getXVelocity(int), #getYVelocity(int), or #getAxisVelocity(int, int) to retrieve velocity for different axes and/or pointer IDs.
Java documentation for android.view.VelocityTracker.
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.
Properties
| Name | Description |
|---|---|
| Class |
Returns the runtime class of this |
| Handle |
The handle to the underlying Android instance. (Inherited from Object) |
| JniIdentityHashCode |
Gets the identity hash code assigned to this Java peer by the interop runtime. (Inherited from Object) |
| JniManagedPeerState |
Gets the state flags last assigned by the runtime. (Inherited from JavaObject) |
| JniPeerMembers |
Gets the JNI peer metadata used by the .NET for Android binding runtime. |
| PeerReference |
Gets the JNI object reference for this Java peer. (Inherited from Object) |
| ThresholdClass |
This API supports the Mono for Android infrastructure and is not intended to be used directly from your code. (Inherited from Object) |
| ThresholdType |
This API supports the Mono for Android infrastructure and is not intended to be used directly from your code. (Inherited from Object) |
| XVelocity |
Retrieve the last computed X velocity. |
| YVelocity |
Retrieve the last computed Y velocity. |
Methods
| Name | Description |
|---|---|
| AddMovement(MotionEvent) |
Add a user's movement to the tracker. |
| Clear() |
Reset the velocity tracker back to its initial state. |
| Clone() |
Creates and returns a copy of this object. (Inherited from Object) |
| ComputeCurrentVelocity(Int32, Single) |
Compute the current velocity based on the points that have been collected. |
| ComputeCurrentVelocity(Int32) |
Equivalent to invoking |
| Construct(JniObjectReference, JniObjectReferenceOptions) |
Delegates construction of this peer to the runtime's value manager. (Inherited from JavaObject) |
| Dispose() |
Releases the resources held by this Java peer. (Inherited from Object) |
| Dispose(Boolean) |
Releases the resources held by this Java peer. (Inherited from Object) |
| DisposeUnlessReferenced() |
Asks the value manager to dispose this peer unless its mapping retains this same managed instance. (Inherited from JavaObject) |
| Equals(Object) |
Tests whether another managed peer refers to the same Java object. (Inherited from JavaObject) |
| Equals(Object) |
Indicates whether some other object is "equal to" this one. (Inherited from Object) |
| GetAxisVelocity(Axis, Int32) |
Retrieve the last computed velocity for a given motion axis. |
| GetAxisVelocity(Axis) |
Equivalent to calling |
| GetHashCode() |
Returns a hash code value for the object. (Inherited from Object) |
| GetXVelocity(Int32) |
Retrieve the last computed X velocity. |
| GetYVelocity(Int32) |
Retrieve the last computed Y velocity. |
| IsAxisSupported(Axis) |
Checks whether a given velocity-trackable |
| JavaFinalize() |
Obsolete.
Called by the garbage collector on an object when garbage collection determines that there are no more references to the object. (Inherited from Object) |
| 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) |
| Obtain() |
Retrieve a new VelocityTracker object to watch the velocity of a motion. |
| Recycle() |
Return a VelocityTracker object back to be re-used by others. |
| SetHandle(IntPtr, JniHandleOwnership) |
Sets the Handle property. (Inherited from Object) |
| SetPeerReference(JniObjectReference, JniObjectReferenceOptions) |
Stores a reference value in the control block without creating a JNI reference copy. (Inherited from JavaObject) |
| ToArray<T>() |
Creates a managed array from this Java array wrapper. (Inherited from Object) |
| ToString() |
Returns a string representation of the object. (Inherited from Object) |
| UnregisterFromRuntime() |
Unregisters this Java peer from the interop runtime. (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) |
Explicit Interface Implementations
| Name | Description |
|---|---|
| IJavaPeerable.Disposed() |
Marks this peer as disposed and calls |
| IJavaPeerable.Finalized() |
Marks this peer as disposed and calls |
| IJavaPeerable.JniObjectReferenceControlBlock |
Gets the native control-block pointer used by this peer. (Inherited from JavaObject) |
| IJavaPeerable.SetJniIdentityHashCode(Int32) |
Stores the identity hash code supplied by the runtime. (Inherited from JavaObject) |
| IJavaPeerable.SetJniManagedPeerState(JniManagedPeerStates) |
Replaces the stored managed peer state flags. (Inherited from JavaObject) |
| IJavaPeerable.SetPeerReference(JniObjectReference) |
Updates the peer reference and releases a disposed peer's control block when the reference is invalid. (Inherited from JavaObject) |
Extension Methods
| Name | Description |
|---|---|
| GetJniTypeName(IJavaPeerable) |
Gets the JNI name of the type of the instance |
| JavaAs<TResult>(IJavaPeerable) |
Try to coerce |
| JavaCast<TResult>(IJavaObject) |
Performs an Android runtime-checked type conversion. |
| JavaCast<TResult>(IJavaObject) |
Reuses a compatible managed peer or obtains a wrapper of the requested type. |
| TryJavaCast<TResult>(IJavaPeerable, TResult) |
Try to coerce |