ScrollerCompat

Added in 1.1.0
Deprecated in 1.1.0

public final class ScrollerCompat

Provides access to new Scroller APIs when available.

This class provides a platform version-independent mechanism for obeying the current device's preferred scroll physics and fling behavior. It offers a subset of the APIs from Scroller or OverScroller.

Summary

Public methods
void

This method is deprecated.

Use abortAnimation directly.
boolean

This method is deprecated.

Use computeScrollOffset directly.
static ScrollerCompat
create(Context context)

This method is deprecated.

Use OverScroller constructor directly.
static ScrollerCompat
create(Context context, Interpolator interpolator)

This method is deprecated.

Use OverScroller constructor directly.
void
fling(
    int startX,
    int startY,
    int velocityX,
    int velocityY,
    int minX,
    int maxX,
    int minY,
    int maxY
)

This method is deprecated.

Use fling directly.
void
fling(
    int startX,
    int startY,
    int velocityX,
    int velocityY,
    int minX,
    int maxX,
    int minY,
    int maxY,
    int overX,
    int overY
)

This method is deprecated.

Use fling directly.
float

This method is deprecated.

Use getCurrVelocity directly.
int

This method is deprecated.

Use getCurrX directly.
int

This method is deprecated.

Use getCurrY directly.
int

This method is deprecated.

Use getFinalX directly.
int

This method is deprecated.

Use getFinalY directly.
boolean

This method is deprecated.

Use isFinished directly.
boolean

This method is deprecated.

Use isOverScrolled directly.
void
notifyHorizontalEdgeReached(int startX, int finalX, int overX)

This method is deprecated.

Use notifyHorizontalEdgeReached directly.
void
notifyVerticalEdgeReached(int startY, int finalY, int overY)

This method is deprecated.

Use notifyVerticalEdgeReached directly.
boolean
springBack(int startX, int startY, int minX, int maxX, int minY, int maxY)

This method is deprecated.

Use springBack directly.
void
startScroll(int startX, int startY, int dx, int dy)

This method is deprecated.

Use getCurrX directly.
void
startScroll(int startX, int startY, int dx, int dy, int duration)

This method is deprecated.

Use startScroll directly.

Public methods

abortAnimation

Added in 1.1.0
Deprecated in 1.1.0
public void abortAnimation()

Stops the animation. Aborting the animation causes the scroller to move to the final x and y position.

computeScrollOffset

Added in 1.1.0
Deprecated in 1.1.0
public boolean computeScrollOffset()

Call this when you want to know the new location. If it returns true, the animation is not yet finished. loc will be altered to provide the new location.

create

Added in 1.1.0
Deprecated in 1.1.0
public static ScrollerCompat create(Context context)

create

Added in 1.1.0
Deprecated in 1.1.0
public static ScrollerCompat create(Context context, Interpolator interpolator)

fling

Added in 1.1.0
Deprecated in 1.1.0
public void fling(
    int startX,
    int startY,
    int velocityX,
    int velocityY,
    int minX,
    int maxX,
    int minY,
    int maxY
)

Start scrolling based on a fling gesture. The distance travelled will depend on the initial velocity of the fling.

Parameters
int startX

Starting point of the scroll (X)
int startY

Starting point of the scroll (Y)
int velocityX

Initial velocity of the fling (X) measured in pixels per second.
int velocityY

Initial velocity of the fling (Y) measured in pixels per second
int minX

Minimum X value. The scroller will not scroll past this point.
int maxX

Maximum X value. The scroller will not scroll past this point.
int minY

Minimum Y value. The scroller will not scroll past this point.
int maxY

Maximum Y value. The scroller will not scroll past this point.

fling

Added in 1.1.0
Deprecated in 1.1.0
public void fling(
    int startX,
    int startY,
    int velocityX,
    int velocityY,
    int minX,
    int maxX,
    int minY,
    int maxY,
    int overX,
    int overY
)

Start scrolling based on a fling gesture. The distance travelled will depend on the initial velocity of the fling.

Parameters
int startX

Starting point of the scroll (X)
int startY

Starting point of the scroll (Y)
int velocityX

Initial velocity of the fling (X) measured in pixels per second.
int velocityY

Initial velocity of the fling (Y) measured in pixels per second
int minX

Minimum X value. The scroller will not scroll past this point.
int maxX

Maximum X value. The scroller will not scroll past this point.
int minY

Minimum Y value. The scroller will not scroll past this point.
int maxY

Maximum Y value. The scroller will not scroll past this point.
int overX

Overfling range. If >0, horizontal overfling in either direction will be possible.
int overY

Overfling range. If >0, vertical overfling in either direction will be possible.

getCurrVelocity

Added in 1.1.0
Deprecated in 1.1.0
public float getCurrVelocity()

Returns the current velocity on platform versions that support it.

This method should only be used as input for nonessential visual effects such as EdgeEffectCompat.

Returns
float

The original velocity less the deceleration. Result may be negative.

getCurrX

Added in 1.1.0
Deprecated in 1.1.0
public int getCurrX()

Returns the current X offset in the scroll.

Returns
int

The new X offset as an absolute distance from the origin.

getCurrY

Added in 1.1.0
Deprecated in 1.1.0
public int getCurrY()

Returns the current Y offset in the scroll.

Returns
int

The new Y offset as an absolute distance from the origin.

getFinalX

Added in 1.1.0
Deprecated in 1.1.0
public int getFinalX()
Returns
int

The final X position for the scroll in progress, if known.

getFinalY

Added in 1.1.0
Deprecated in 1.1.0
public int getFinalY()
Returns
int

The final Y position for the scroll in progress, if known.

isFinished

Added in 1.1.0
Deprecated in 1.1.0
public boolean isFinished()

Returns whether the scroller has finished scrolling.

Returns
boolean

True if the scroller has finished scrolling, false otherwise.

isOverScrolled

Added in 1.1.0
Deprecated in 1.1.0
public boolean isOverScrolled()

Returns whether the current Scroller is currently returning to a valid position. Valid bounds were provided by the fling method. One should check this value before calling startScroll as the interpolation currently in progress to restore a valid position will then be stopped. The caller has to take into account the fact that the started scroll will start from an overscrolled position.

Returns
boolean

true when the current position is overscrolled and in the process of interpolating back to a valid value.

notifyHorizontalEdgeReached

Added in 1.1.0
Deprecated in 1.1.0
public void notifyHorizontalEdgeReached(int startX, int finalX, int overX)

Notify the scroller that we've reached a horizontal boundary. Normally the information to handle this will already be known when the animation is started, such as in a call to one of the fling functions. However there are cases where this cannot be known in advance. This function will transition the current motion and animate from startX to finalX as appropriate.

Parameters
int startX

Starting/current X position
int finalX

Desired final X position
int overX

Magnitude of overscroll allowed. This should be the maximum desired distance from finalX. Absolute value - must be positive.

notifyVerticalEdgeReached

Added in 1.1.0
Deprecated in 1.1.0
public void notifyVerticalEdgeReached(int startY, int finalY, int overY)

Notify the scroller that we've reached a vertical boundary. Normally the information to handle this will already be known when the animation is started, such as in a call to one of the fling functions. However there are cases where this cannot be known in advance. This function will animate a parabolic motion from startY to finalY.

Parameters
int startY

Starting/current Y position
int finalY

Desired final Y position
int overY

Magnitude of overscroll allowed. This should be the maximum desired distance from finalY. Absolute value - must be positive.

springBack

Added in 1.1.0
Deprecated in 1.1.0
public boolean springBack(int startX, int startY, int minX, int maxX, int minY, int maxY)

Call this when you want to 'spring back' into a valid coordinate range.

Parameters
int startX

Starting X coordinate
int startY

Starting Y coordinate
int minX

Minimum valid X value
int maxX

Maximum valid X value
int minY

Minimum valid Y value
int maxY

Maximum valid Y value
Returns
boolean

true if a springback was initiated, false if startX and startY were already within the valid range.

startScroll

Added in 1.1.0
Deprecated in 1.1.0
public void startScroll(int startX, int startY, int dx, int dy)

Start scrolling by providing a starting point and the distance to travel. The scroll will use the default value of 250 milliseconds for the duration.

Parameters
int startX

Starting horizontal scroll offset in pixels. Positive numbers will scroll the content to the left.
int startY

Starting vertical scroll offset in pixels. Positive numbers will scroll the content up.
int dx

Horizontal distance to travel. Positive numbers will scroll the content to the left.
int dy

Vertical distance to travel. Positive numbers will scroll the content up.

startScroll

Added in 1.1.0
Deprecated in 1.1.0
public void startScroll(int startX, int startY, int dx, int dy, int duration)

Start scrolling by providing a starting point and the distance to travel.

Parameters
int startX

Starting horizontal scroll offset in pixels. Positive numbers will scroll the content to the left.
int startY

Starting vertical scroll offset in pixels. Positive numbers will scroll the content up.
int dx

Horizontal distance to travel. Positive numbers will scroll the content to the left.
int dy

Vertical distance to travel. Positive numbers will scroll the content up.
int duration

Duration of the scroll in milliseconds.