EdgeEffectCompat

Kotlin |Java

class EdgeEffectCompat

kotlin.Any
↳	androidx.core.widget.EdgeEffectCompat

Helper for accessing android.widget.EdgeEffect. This class is used to access android.widget.EdgeEffect on platform versions that support it. When running on older platforms it will result in no-ops. It should be used by views that wish to use the standard Android visual effects at the edges of scrolling containers.

Summary

Public constructors
`<init>(context: Context!)` Construct a new EdgeEffect themed using the given context.

Public methods
Boolean	`draw(canvas: Canvas!)` Draw into the provided canvas.
Unit	`finish()` Immediately finish the current animation.
Boolean	`isFinished()` Reports if this EdgeEffectCompat's animation is finished.
Boolean	`onAbsorb(velocity: Int)` Call when the effect absorbs an impact at the given velocity.
Boolean	`onPull(deltaDistance: Float)` A view should call this when content is pulled away from an edge by the user.
Boolean	`onPull(deltaDistance: Float, displacement: Float)` A view should call this when content is pulled away from an edge by the user.
static Unit	`onPull(@NonNull edgeEffect: EdgeEffect, deltaDistance: Float, displacement: Float)` A view should call this when content is pulled away from an edge by the user.
Boolean	`onRelease()` Call when the object is released after being pulled.
Unit	`setSize(width: Int, height: Int)` Set the size of this edge effect in pixels.

Public constructors

<init>

EdgeEffectCompat(context: Context!)

Deprecated: Use EdgeEffect constructor directly.

Construct a new EdgeEffect themed using the given context.

Note: On platform versions that do not support EdgeEffect, all operations on the newly constructed object will be mocked/no-ops.

Parameters
`context`	Context!: Context to use for theming the effect

Public methods

draw

fun draw(canvas: Canvas!): Boolean

Deprecated: Use EdgeEffect#draw(Canvas) directly.

Draw into the provided canvas. Assumes that the canvas has been rotated accordingly and the size has been set. The effect will be drawn the full width of X=0 to X=width, beginning from Y=0 and extending to some factor < 1.f of height.

Parameters
`canvas`	Canvas!: Canvas to draw into

Return
Boolean: true if drawing should continue beyond this frame to continue the animation

finish

fun finish(): Unit

Deprecated: Use EdgeEffect#finish() directly.

Immediately finish the current animation. After this call isFinished() will return true.

isFinished

fun isFinished(): Boolean

Deprecated: Use EdgeEffect#isFinished() directly.

Reports if this EdgeEffectCompat's animation is finished. If this method returns false after a call to draw(Canvas) the host widget should schedule another drawing pass to continue the animation.

Return
Boolean: true if animation is finished, false if drawing should continue on the next frame.

onAbsorb

fun onAbsorb(velocity: Int): Boolean

Deprecated: Use EdgeEffect#onAbsorb(int) directly.

Call when the effect absorbs an impact at the given velocity. Used when a fling reaches the scroll boundary.

When using a android.widget.Scroller or android.widget.OverScroller, the method getCurrVelocity will provide a reasonable approximation to use here.

Parameters
`velocity`	Int: Velocity at impact in pixels per second.

Return
Boolean: true if the host view should invalidate, false if it should not.

onPull

fun onPull(deltaDistance: Float): Boolean

Deprecated: Use onPull(EdgeEffect, float, float).

A view should call this when content is pulled away from an edge by the user. This will update the state of the current visual effect and its associated animation. The host view should always android.view.View#invalidate() if this method returns true and draw the results accordingly.

Parameters
`deltaDistance`	Float: Change in distance since the last call. Values may be 0 (no change) to 1.f (full length of the view) or negative values to express change back toward the edge reached to initiate the effect.

Return
Boolean: true if the host view should call invalidate, false if it should not.

onPull

fun onPull(
    deltaDistance: Float, 
    displacement: Float
): Boolean

Deprecated: Use EdgeEffect#onPull(float) directly.

Parameters
`deltaDistance`	Float: Change in distance since the last call. Values may be 0 (no change) to 1.f (full length of the view) or negative values to express change back toward the edge reached to initiate the effect.
`displacement`	Float: The displacement from the starting side of the effect of the point initiating the pull. In the case of touch this is the finger position. Values may be from 0-1.

Return
Boolean: true if the host view should call invalidate, false if it should not.

onPull

static fun onPull(
    @NonNull edgeEffect: EdgeEffect, 
    deltaDistance: Float, 
    displacement: Float
): Unit

Parameters
`edgeEffect`	EdgeEffect: The EdgeEffect that is attached to the view that is getting pulled away from an edge by the user.
`deltaDistance`	Float: Change in distance since the last call. Values may be 0 (no change) to 1.f (full length of the view) or negative values to express change back toward the edge reached to initiate the effect.
`displacement`	Float: The displacement from the starting side of the effect of the point initiating the pull. In the case of touch this is the finger position. Values may be from 0-1.

See Also

EdgeEffect#onPull(float, float)

onRelease

fun onRelease(): Boolean

Deprecated: Use EdgeEffect#onRelease() directly.

Call when the object is released after being pulled. This will begin the "decay" phase of the effect. After calling this method the host view should android.view.View#invalidate() if this method returns true and thereby draw the results accordingly.

Return
Boolean: true if the host view should invalidate, false if it should not.

setSize

fun setSize(
    width: Int, 
    height: Int
): Unit

Deprecated: Use EdgeEffect#setSize(int, int) directly.

Set the size of this edge effect in pixels.

Parameters
`width`	Int: Effect width in pixels
`height`	Int: Effect height in pixels