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

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

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

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.