Compartilhar via


IScrollCaptureCallback Interface

Definition

A ScrollCaptureCallback is responsible for providing rendered snapshots of scrolling content for the scroll capture system.

[Android.Runtime.Register("android/view/ScrollCaptureCallback", "", "Android.Views.IScrollCaptureCallbackInvoker", ApiSince=31)]
public interface IScrollCaptureCallback : Android.Runtime.IJavaObject, IDisposable, Java.Interop.IJavaPeerable
[<Android.Runtime.Register("android/view/ScrollCaptureCallback", "", "Android.Views.IScrollCaptureCallbackInvoker", ApiSince=31)>]
type IScrollCaptureCallback = interface
    interface IJavaObject
    interface IDisposable
    interface IJavaPeerable
Attributes
Implements

Remarks

A ScrollCaptureCallback is responsible for providing rendered snapshots of scrolling content for the scroll capture system. A single callback is responsible for providing support to a single scrolling UI element. At request time, the system will select the best candidate from among all callbacks registered within the window.

A callback is assigned to a View using View#setScrollCaptureCallback, or to the window as Window#registerScrollCaptureCallback. The point where the callback is registered defines the frame of reference for the bounds measurements used.

<b>Terminology</b> <dl> <dt>Containing View</dt> <dd>The view on which this callback is attached, or the root view of the window if the callback is assigned directly to a window.</dd>

<dt>Scroll Bounds</dt> <dd>A rectangle which describes an area within the containing view where scrolling content appears. This may be the entire view or any rectangle within. This defines a frame of reference for requests as well as the width and maximum height of a single request.</dd>

<dt>Scroll Delta</dt> <dd>The distance the scroll position has moved since capture started. Implementations are responsible for tracking changes in vertical scroll position during capture. This is required to map the capture area to the correct location, given the current scroll position.

<dt>Capture Area</dt> <dd>A rectangle which describes the area to capture, relative to scroll bounds. The vertical position remains relative to the starting scroll position and any movement since ("Scroll Delta") should be subtracted to locate the correct local position, and scrolled into view as necessary. </dd> </dl>

Java documentation for android.view.ScrollCaptureCallback.

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

Handle

Gets the JNI value of the underlying Android object.

(Inherited from IJavaObject)
JniIdentityHashCode

Returns the value of java.lang.System.identityHashCode() for the wrapped instance.

(Inherited from IJavaPeerable)
JniManagedPeerState

State of the managed peer.

(Inherited from IJavaPeerable)
JniPeerMembers

Member access and invocation support.

(Inherited from IJavaPeerable)
PeerReference

Returns a JniObjectReference of the wrapped Java object instance.

(Inherited from IJavaPeerable)

Methods

Disposed()

Called when the instance has been disposed.

(Inherited from IJavaPeerable)
DisposeUnlessReferenced()

If there are no outstanding references to this instance, then calls Dispose(); otherwise, does nothing.

(Inherited from IJavaPeerable)
Finalized()

Called when the instance has been finalized.

(Inherited from IJavaPeerable)
OnScrollCaptureEnd(IRunnable)

Signals that capture has ended.

OnScrollCaptureImageRequest(ScrollCaptureSession, CancellationSignal, Rect, IConsumer)

An image capture has been requested from the scrolling content.

OnScrollCaptureSearch(CancellationSignal, IConsumer)

The system is searching for the appropriate scrolling container to capture and would like to know the size and position of scrolling content handled by this callback.

OnScrollCaptureStart(ScrollCaptureSession, CancellationSignal, IRunnable)

Scroll Capture has selected this callback to provide the scrolling image content.

SetJniIdentityHashCode(Int32)

Set the value returned by JniIdentityHashCode.

(Inherited from IJavaPeerable)
SetJniManagedPeerState(JniManagedPeerStates) (Inherited from IJavaPeerable)
SetPeerReference(JniObjectReference)

Set the value returned by PeerReference.

(Inherited from IJavaPeerable)
UnregisterFromRuntime()

Unregister this instance so that the runtime will not return it from future Java.Interop.JniRuntime+JniValueManager.PeekValue invocations.

(Inherited from IJavaPeerable)

Extension Methods

JavaCast<TResult>(IJavaObject)

Performs an Android runtime-checked type conversion.

JavaCast<TResult>(IJavaObject)
GetJniTypeName(IJavaPeerable)

Applies to