ListViewAutoScrollHelper

Added in 1.1.0

Kotlin |Java

public class ListViewAutoScrollHelper extends AutoScrollHelper

java.lang.Object
↳	androidx.core.widget.AutoScrollHelper
	↳	androidx.core.widget.ListViewAutoScrollHelper

An implementation of AutoScrollHelper that knows how to scroll through a ListView.

Summary

Public constructors
`ListViewAutoScrollHelper(@NonNull ListView target)`

Public methods
`boolean`	`canTargetScrollHorizontally(int direction)` Override this method to return whether the target view can be scrolled horizontally in a certain direction.
`boolean`	`canTargetScrollVertically(int direction)` Override this method to return whether the target view can be scrolled vertically in a certain direction.
`void`	`scrollTargetBy(int deltaX, int deltaY)` Override this method to scroll the target view by the specified number of pixels.

Inherited Constants

From androidx.core.widget.AutoScrollHelper

`static final int`	`EDGE_TYPE_INSIDE = 0` Edge type that specifies an activation area starting at the view bounds and extending inward.
`static final int`	`EDGE_TYPE_INSIDE_EXTEND = 1` Edge type that specifies an activation area starting at the view bounds and extending inward.
`static final int`	`EDGE_TYPE_OUTSIDE = 2` Edge type that specifies an activation area starting at the view bounds and extending outward.
`static final float`	`NO_MAX = 3.4028235E38f` Constant passed to `setMaximumEdges`, `setMaximumVelocity`, or `setMinimumVelocity`.
`static final float`	`NO_MIN = 0.0f` Constant passed to `setMaximumEdges`, or `setMaximumVelocity`, or `setMinimumVelocity`.
`static final float`	`RELATIVE_UNSPECIFIED = 0.0f` Constant passed to `setRelativeEdges` or `setRelativeVelocity`.

Inherited methods

From androidx.core.widget.AutoScrollHelper

`boolean`	`isEnabled()`
`boolean`	`isExclusive()` Indicates whether the scroll helper handles touch events exclusively during scrolling.
`boolean`	`onTouch(View v, MotionEvent event)` Handles touch events by activating automatic scrolling, adjusting scroll velocity, or stopping.
`@NonNull AutoScrollHelper`	`setActivationDelay(int delayMillis)` Sets the delay after entering an activation edge before activation of auto-scrolling.
`@NonNull AutoScrollHelper`	`setEdgeType(int type)` Sets the activation edge type, one of:
`AutoScrollHelper`	`setEnabled(boolean enabled)` Sets whether the scroll helper is enabled and should respond to touch events.
`AutoScrollHelper`	`setExclusive(boolean exclusive)` Enables or disables exclusive handling of touch events during scrolling.
`@NonNull AutoScrollHelper`	`setMaximumEdges(float horizontalMax, float verticalMax)` Sets the absolute maximum edge size.
`@NonNull AutoScrollHelper`	`setMaximumVelocity(float horizontalMax, float verticalMax)` Sets the absolute maximum scrolling velocity.
`@NonNull AutoScrollHelper`	`setMinimumVelocity(float horizontalMin, float verticalMin)` Sets the absolute minimum scrolling velocity.
`@NonNull AutoScrollHelper`	`setRampDownDuration(int durationMillis)` Sets the amount of time after de-activation of auto-scrolling that is takes to slow to a stop.
`@NonNull AutoScrollHelper`	`setRampUpDuration(int durationMillis)` Sets the amount of time after activation of auto-scrolling that is takes to reach target velocity for the current touch position.
`@NonNull AutoScrollHelper`	`setRelativeEdges(float horizontal, float vertical)` Sets the activation edge size relative to the host view's dimensions.
`@NonNull AutoScrollHelper`	`setRelativeVelocity(float horizontal, float vertical)` Sets the target scrolling velocity relative to the host view's dimensions.

From android.view.View.OnTouchListener

abstract boolean

onTouch(View p, MotionEvent p1)

Public constructors

Added in 1.1.0

public ListViewAutoScrollHelper(@NonNull ListView target)

Public methods

canTargetScrollHorizontally

Added in 1.16.0-alpha01

public boolean canTargetScrollHorizontally(int direction)

Override this method to return whether the target view can be scrolled horizontally in a certain direction.

Parameters
`int direction`	Negative to check scrolling left, positive to check scrolling right.

Returns
`boolean`	true if the target view is able to horizontally scroll in the specified direction.

canTargetScrollVertically

Added in 1.16.0-alpha01

public boolean canTargetScrollVertically(int direction)

Override this method to return whether the target view can be scrolled vertically in a certain direction.

Parameters
`int direction`	Negative to check scrolling up, positive to check scrolling down.

Returns
`boolean`	true if the target view is able to vertically scroll in the specified direction.

scrollTargetBy

Added in 1.16.0-alpha01

public void scrollTargetBy(int deltaX, int deltaY)

Override this method to scroll the target view by the specified number of pixels.

Parameters
`int deltaX`	The number of pixels to scroll by horizontally.
`int deltaY`	The number of pixels to scroll by vertically.