NestedScrollingChild3
public
interface
NestedScrollingChild3
implements
NestedScrollingChild2
| androidx.core.view.NestedScrollingChild3 |
This interface should be implemented by View subclasses that wish
to support dispatching nested scrolling operations to a cooperating parent
ViewGroup.
Classes implementing this interface should create a final instance of a
NestedScrollingChildHelper as a field and delegate any View methods to the
NestedScrollingChildHelper methods of the same signature.
Views invoking nested scrolling functionality should always do so from the relevant
ViewCompat, ViewGroupCompat or ViewParentCompat compatibility
shim static methods. This ensures interoperability with nested scrolling views on all versions
of Android.
Summary
Public methods | |
|---|---|
abstract
void
|
dispatchNestedScroll(int dxConsumed, int dyConsumed, int dxUnconsumed, int dyUnconsumed, int[] offsetInWindow, int type, int[] consumed)
Dispatch one step of a nested scroll in progress. |
Inherited methods | |
|---|---|
Public methods
dispatchNestedScroll
public abstract void dispatchNestedScroll (int dxConsumed,
int dyConsumed,
int dxUnconsumed,
int dyUnconsumed,
int[] offsetInWindow,
int type,
int[] consumed)
Dispatch one step of a nested scroll in progress.
Implementations of views that support nested scrolling should call this to report
info about a scroll in progress to the current nested scrolling parent. If a nested scroll
is not currently in progress or nested scrolling is not
enabled for this view this method does nothing.
Compatible View implementations should also call
dispatchNestedPreScroll before
consuming a component of the scroll event themselves.
The original nested scrolling child (where the input events were received to start the
scroll) must provide a non-null consumed parameter with values {0, 0}.
| Parameters | |
|---|---|
dxConsumed |
int: Horizontal distance in pixels consumed by this view during this scroll step |
dyConsumed |
int: Vertical distance in pixels consumed by this view during this scroll step |
dxUnconsumed |
int: Horizontal scroll distance in pixels not consumed by this view |
dyUnconsumed |
int: Horizontal scroll distance in pixels not consumed by this view |
offsetInWindow |
int: Optional. If not null, on return this will contain the offset
in local view coordinates of this view from before this operation
to after it completes. View implementations may use this to adjust
expected input coordinate tracking. |
type |
int: the type of input which cause this scroll event |
consumed |
int: Output. Upon this method returning, will contain the original values plus any
scroll distances consumed by all of this view's nested scrolling parents up
the view hierarchy. Index 0 for the x dimension, and index 1 for the y
dimension |