MotionLayout

public class MotionLayout
extends ConstraintLayout implements NestedScrollingParent3

java.lang.Object
   ↳ android.view.View
     ↳ android.view.ViewGroup
       ↳ androidx.constraintlayout.widget.ConstraintLayout
         ↳ androidx.constraintlayout.motion.widget.MotionLayout


A subclass of ConstraintLayout that supports animating between various states Added in 2.0

A MotionLayout is a subclass of ConstraintLayout which supports transitions between between various states (ConstraintSet) defined in MotionScenes.

Note: MotionLayout is available as a support library that you can use on Android systems starting with API level 14 (ICS).

MotionLayout links to and requires a MotionScene file. The file contains one top level tag "MotionScene"

LayoutDescription

TagsDescription
<StateSet> Describes states supported by the system (optional)
<ConstraintSet> Describes a constraint set
<Transition> Describes a transition between two states or ConstraintSets
<ViewTransition> Describes a transition of a View within a states or ConstraintSets

Transition

AttributesDescription
android:id The id of the Transition
constraintSetStart ConstraintSet to be used as the start constraints or a layout file to get the constraint from
constraintSetEnd ConstraintSet to be used as the end constraints or a layout file to get the constraint from
motionInterpolator The ability to set an overall interpolation (easeInOut, linear, etc.)
duration Length of time to take to perform the transition
staggered Overrides the Manhattan distance from the top most view in the list of views.
  • For any view of stagger value S(Vi)
  • With the transition stagger value of TS (from 0.0 - 1.0)
  • The duration of the animation is duration
  • The views animation duration DS = duration * (1 -TS)
  • Call the stagger fraction SFi = (S(Vi) - S(V0)) / (S(Vn) - S(V0))
  • The view starts animating at: (duration-DS) * SFi
pathMotionArc The path will move in arc (quarter ellipses) key words {startVertical | startHorizontal | flip | none }
autoTransition automatically transition from one state to another. key words {none, jumpToStart, jumpToEnd, animateToStart, animateToEnd}
transitionFlags flags that adjust the behaviour of Transitions. supports {none, beginOnFirstDraw} begin on first draw forces the transition's clock to start when it is first displayed not when the begin is called
layoutDuringTransition Configures MotionLayout on how to react to requestLayout calls during transitions. Allowed values are {ignoreRequest, honorRequest}
<OnSwipe> Adds support for touch handling (optional)
<OnClick> Adds support for triggering transition (optional)
<KeyFrameSet> Describes a set of Key object which modify the animation between constraint sets.
  • A transition is typically defined by specifying its start and end ConstraintSets. You also have the possibility to not specify them, in which case such transition will become a Default transition. That Default transition will be applied between any state change that isn't explicitly covered by a transition.
  • The starting state of the MotionLayout is defined to be the constraintSetStart of the first transition.
  • If no transition is specified (or only a default Transition) the MotionLayout tag must contain a app:currentState to define the starting state of the MotionLayout

ViewTransition

AttributesDescription
android:id The id of the ViewTransition
viewTransitionMode currentState, allStates, noState transition affect the state of the view in the current constraintSet or all ConstraintSets or non if noState the ViewTransitions are run asynchronous
onStateTransition actionDown or actionUp run transition if on touch down or up if view matches motionTarget
motionInterpolator The ability to set an overall interpolation key words {easeInOut, linear, etc.}
duration Length of time to take to perform the ViewTransition
pathMotionArc The path will move in arc (quarter ellipses) key words {startVertical | startHorizontal | flip | none }
motionTarget Apply ViewTransition matching this string or id.
setsTag set this tag at end of transition
clearsTag clears this tag at end of transition
ifTagSet run transition if this tag is set on view
ifTagNotSet run transition if this tag is not set on view/td>
<OnSwipe> Adds support for touch handling (optional)
<OnClick> Adds support for triggering transition (optional)
<KeyFrameSet> Describes a set of Key object which modify the animation between constraint sets.
  • A Transition is typically defined by specifying its start and end ConstraintSets. You also have the possibility to not specify them, in which case such transition will become a Default transition. That Default transition will be applied between any state change that isn't explicitly covered by a transition.
  • The starting state of the MotionLayout is defined to be the constraintSetStart of the first transition.
  • If no transition is specified (or only a default Transition) the MotionLayout tag must contain a app:currentState to define the starting state of the MotionLayout

OnSwipe (optional)

AttributesDescription
touchAnchorId Have the drag act as if it is moving the "touchAnchorSide" of this object
touchRegionId Limits the region that the touch can be start in to the bounds of this view (even if the view is invisible)
touchAnchorSide The side of the object to move with {top|left|right|bottom}
maxVelocity limit the maximum velocity (in progress/sec) of the animation will on touch up. Default 4
dragDirection which side to swipe from {dragUp|dragDown|dragLeft|dragRight}
maxAcceleration how quickly the animation will accelerate (progress/sec/sec) and decelerate on touch up. Default 1.2
dragScale scale factor to adjust the swipe by. (e.g. 0.5 would require you to move 2x as much)
dragThreshold How much to drag before swipe gesture runs. Important for mult-direction swipe. Default is 10. 1 is very sensitive.
moveWhenScrollAtTop If the swipe is scrolling and View (such as RecyclerView or NestedScrollView) do scroll and transition happen at the same time
onTouchUp Support for various swipe modes autoComplete,autoCompleteToStart,autoCompleteToEnd,stop,decelerate,decelerateAndComplete

OnClick (optional)

AttributesDescription
motionTarget What view triggers Transition.
clickAction Direction for buttons to move the animation. Or (|) combination of: toggle, transitionToEnd, transitionToStart, jumpToEnd, jumpToStart

StateSet

defaultState The constraint set or layout to use
<State> The side of the object to move

State

android:id Id of the State
constraints Id of the ConstraintSet or the Layout file
<Variant> a different constraintSet/layout to choose if the with or height matches

Variant

region_widthLessThan Match if width less than
region_widthMoreThan Match if width more than
region_heightLessThan Match if height less than
region_heightMoreThan Match if height more than
constraints Id of the ConstraintSet or layout

ConstraintSet

android:id The id of the ConstraintSet
deriveConstraintsFrom The id of another constraintSet which defines the constraints not define in this set. If not specified the layout defines the undefined constraints.
<Constraint> A ConstraintLayout Constraints + other attributes associated with a view

Constraint

Constraint supports two forms:

1: All of ConstraintLayout + the ones listed below + <CustomAttribute> .

Or

2: Combination of tags: <Layout> <PropertySet> <Transform> <Motion> <CustomAttribute> . The advantage of using these is that if not present the attributes are taken from the base layout file. This saves from replicating all the layout tags if only a Motion tag is needed. If is used then all layout attributes in the base are ignored.

android:id Id of the View
[ConstraintLayout attributes] Any attribute that is part of ConstraintLayout layout is allowed
[Standard View attributes] A collection of view attributes supported by the system (see below)
transitionEasing define an easing curve to be used when animating from this point (e.g. curve(1.0,0,0,1.0)) or key words {standard | accelerate | decelerate | linear}
pathMotionArc the path will move in arc (quarter ellipses) or key words {startVertical | startHorizontal | none }
transitionPathRotate (float) rotate object relative to path taken
drawPath draw the path the layout will animate animate
progress call method setProgress(float) on this view (used to talk to nested ConstraintLayouts etc.)
<CustomAttribute> call a set"name" method via reflection
<Layout> Attributes for the ConstraintLayout e.g. layout_constraintTop_toTopOf
<PropertySet> currently only visibility, alpha, motionProgress,layout_constraintTag.
<Transform> All the view transform API such as android:rotation.
<Motion> Motion Layout control commands such as transitionEasing and pathMotionArc

Layout

[ConstraintLayout attributes] see for attributes

PropertySet

visibility set the Visibility of the view. One of Visible, invisible or gone
alpha setAlpha value
motionProgress using reflection call setProgress
layout_constraintTag a tagging string to identify the type of object

Transform

android:elevation base z depth of the view.
android:rotation rotation of the view, in degrees.
android:rotationX rotation of the view around the x axis, in degrees.
android:rotationY rotation of the view around the y axis, in degrees.
android:scaleX scale of the view in the x direction
android:scaleY scale of the view in the y direction.
android:translationX translation in x of the view. This value is added post-layout to the left property of the view, which is set by its layout.
android:translationY translation in y of the view. This value is added post-layout to th e top property of the view, which is set by its layout
android:translationZ translation in z of the view. This value is added to its elevation.

Motion

transitionEasing Defines an acceleration curve.
pathMotionArc Says the object should move in a quarter ellipse unless the motion is vertical or horizontal
motionPathRotate set the rotation to the path of the object + this angle.
drawPath Debugging utility to draw the motion of the path

CustomAttribute

attributeName The name of the attribute. Case sensitive. ( MyAttr will look for method setMyAttr(...)
customColorValue The value is a color looking setMyAttr(int )
customIntegerValue The value is an integer looking setMyAttr(int )
customFloatValue The value is a float looking setMyAttr(float )
customStringValue The value is a String looking setMyAttr(String )
customDimension The value is a dimension looking setMyAttr(float )
customBoolean The value is true or false looking setMyAttr(boolean )

KeyFrameSet

This is the container for a collection of Key objects (such as KeyPosition) which provide information about how the views should move

<KeyPosition> Controls the layout position during animation
<KeyAttribute> Controls the post layout properties during animation
<KeyCycle> Controls oscillations with respect to position of post layout properties during animation
<KeyTimeCycle> Controls oscillations with respect to time of post layout properties during animation
<KeyTrigger> trigger callbacks into code at fixed point during the animation

KeyPosition

motionTarget Id of the View or a regular expression to match layout_ConstraintTag
framePosition The point along the interpolation 0 = start 100 = end
transitionEasing define an easing curve to be used when animating from this point (e.g. curve(1.0,0,0, 1.0)) or key words {standard | accelerate | decelerate | linear }
pathMotionArc The path will move in arc (quarter ellipses) key words {startVertical | startHorizontal | flip | none }
keyPositionType how this keyframe's deviation for linear path is calculated {deltaRelative | pathRelative|parentRelative}
percentX (float) percent distance from start to end along X axis (deltaRelative) or along the path in pathRelative
percentY (float) Percent distance from start to end along Y axis (deltaRelative) or perpendicular to path in pathRelative
percentWidth (float) Percent of change in the width. Note if the width does not change this has no effect.This overrides sizePercent.
percentHeight (float) Percent of change in the width. Note if the width does not change this has no effect.This overrides sizePercent.
curveFit path is traced
drawPath Draw the path of the objects layout takes useful for debugging
sizePercent If the view changes size this controls how growth of the size. (for fixed size objects use KeyAttributes scaleX/X)
curveFit selects a path based on straight lines or a path based on a monotonic spline {linear|spline}

KeyAttribute

motionTarget Id of the View or a regular expression to match layout_ConstraintTag
framePosition The point along the interpolation 0 = start 100 = end
curveFit selects a path based on straight lines or a path based on a monotonic spline {linear|spline}
transitionEasing Define an easing curve to be used when animating from this point (e.g. curve(1.0,0,0, 1.0)) or key words {standard | accelerate | decelerate | linear }
transitionPathRotate (float) rotate object relative to path taken
drawPath draw the path the layout will animate animate
motionProgress call method setProgress(float) on this view (used to talk to nested ConstraintLayouts etc.)
[standard view attributes](except visibility) A collection of post layout view attributes see below
<CustomAttribute> call a set"name" method via reflection

CustomAttribute

attributeName The name of the attribute. Case sensitive. ( MyAttr will look for method setMyAttr(...)
customColorValue The value is a color looking setMyAttr(int )
customIntegerValue The value is an integer looking setMyAttr(int )
customFloatValue The value is a float looking setMyAttr(float )
customStringValue The value is a String looking setMyAttr(String )
customDimension The value is a dimension looking setMyAttr(float )
customBoolean The value is true or false looking setMyAttr(boolean )

KeyCycle

motionTarget Id of the View or a regular expression to match layout_ConstraintTag
framePosition The point along the interpolation 0 = start 100 = end
[Standard View attributes] A collection of view attributes supported by the system (see below)
waveShape The shape of the wave to generate {sin|square|triangle|sawtooth|reverseSawtooth|cos|bounce}
wavePeriod The number of cycles to loop near this region
waveOffset offset value added to the attribute
transitionPathRotate Cycles applied to rotation relative to the path the view is travelling
progress call method setProgress(float) on this view (used to talk to nested ConstraintLayouts etc.)
<CustomAttribute> call a set"name" method via reflection (limited to floats)

CustomAttribute

attributeName The name of the attribute. Case sensitive. ( MyAttr will look for method setMyAttr(...)
customFloatValue The value is a float looking setMyAttr(float )

KeyTimeCycle

motionTarget Id of the View or a regular expression to match layout_ConstraintTag
framePosition The point along the interpolation 0 = start 100 = end
[Standard View attributes] A collection of view attributes supported by the system (see below)
waveShape The shape of the wave to generate {sin|square|triangle|sawtooth|reverseSawtooth|cos|bounce}
wavePeriod The number of cycles per second
waveOffset offset value added to the attribute
transitionPathRotate Cycles applied to rotation relative to the path the view is travelling
progress call method setProgress(float) on this view (used to talk to nested ConstraintLayouts etc.)
<CustomAttribute> call a set"name" method via reflection (limited to floats)

CustomAttribute

attributeName The name of the attribute. Case sensitive. ( MyAttr will look for method setMyAttr(...)
customFloatValue The value is a float looking setMyAttr(float )

KeyTrigger

motionTarget Id of the View or a regular expression to match layout_ConstraintTag
framePosition The point along the interpolation 0 = start 100 = end
onCross (method name) on crossing this position call this methods on the t arget
onPositiveCross (method name) on forward crossing of the framePosition call this methods on the target
onNegativeCross/td> (method name) backward crossing of the framePosition call this methods on the target
viewTransitionOnCross (ViewTransition Id) start a NoState view transition on crossing or hitting t arget
viewTransitionOnPositiveCross (ViewTransition Id) start a NoState view transition forward crossing of the framePosition or entering target
viewTransitionOnNegativeCross/td> (ViewTransition Id) start a NoState view transition backward crossing of the framePosition or leaving target
triggerSlack (float) do not call trigger again if the framePosition has not moved this fraction away from the trigger point
triggerId (id) call the TransitionListener with this trigger id
motion_postLayoutCollision Define motion pre or post layout. Post layout is more expensive but captures KeyAttributes or KeyCycle motions.
motion_triggerOnCollision (id) Trigger if the motionTarget collides with the other motionTarget

Standard attributes

android:visibility Android view attribute that
android:alpha Android view attribute that
android:elevation base z depth of the view.
android:rotation rotation of the view, in degrees.
android:rotationX rotation of the view around the x axis, in degrees.
android:rotationY rotation of the view around the y axis, in degrees.
android:scaleX scale of the view in the x direction.
android:scaleY scale of the view in the y direction.
android:translationX translation in x of the view.
android:translationY translation in y of the view.
android:translationZ translation in z of the view.

See also:

Summary

Nested classes

interface MotionLayout.MotionTracker

Subclasses can override to build test frameworks 

interface MotionLayout.TransitionListener

Listener for monitoring events about TransitionLayout. 

Constants

int DEBUG_SHOW_NONE

int DEBUG_SHOW_PATH

int DEBUG_SHOW_PROGRESS

int TOUCH_UP_COMPLETE

int TOUCH_UP_COMPLETE_TO_END

int TOUCH_UP_COMPLETE_TO_START

int TOUCH_UP_DECELERATE

int TOUCH_UP_DECELERATE_AND_COMPLETE

int TOUCH_UP_NEVER_TO_END

int TOUCH_UP_NEVER_TO_START

int TOUCH_UP_STOP

int VELOCITY_LAYOUT

int VELOCITY_POST_LAYOUT

int VELOCITY_STATIC_LAYOUT

int VELOCITY_STATIC_POST_LAYOUT

Inherited constants

Fields

public static boolean IS_IN_EDIT_MODE

protected boolean mMeasureDuringTransition

Inherited fields

Public constructors

MotionLayout(Context context)
MotionLayout(Context context, AttributeSet attrs)
MotionLayout(Context context, AttributeSet attrs, int defStyleAttr)

Public methods

void addTransitionListener(MotionLayout.TransitionListener listener)

adds a listener to be notified of drawer events.

boolean applyViewTransition(int viewTransitionId, MotionController motionController)

Apply the view transitions keyFrames to the MotionController.

ConstraintSet cloneConstraintSet(int id)

Creates a ConstraintSet based on an existing constraintSet.

void enableTransition(int transitionID, boolean enable)
void enableViewTransition(int viewTransitionId, boolean enable)

Enable a ViewTransition ID.

void fireTrigger(int triggerId, boolean positive, float progress)

This causes the callback onTransitionTrigger to be called

ConstraintSet getConstraintSet(int id)

Get the ConstraintSet associated with an id This returns a link to the constraintset But in most cases can be used.

int[] getConstraintSetIds()

Get the id's of all constraintSets used by MotionLayout

int getCurrentState()

Return the current state id

ArrayList<MotionScene.Transition> getDefinedTransitions()

Get all Transitions known to the system.

int getEndState()

Gets the state you are currently transition to.

float getProgress()

Get current position during an animation.

int getStartState()

Gets the state you are currently transitioning from.

float getTargetPosition()

Gets the position you are animating to typically 0 or 1.

MotionScene.Transition getTransition(int id)

This returns the internal Transition Structure

Bundle getTransitionState()
long getTransitionTimeMs()

Gets the time of the currently set animation.

float getVelocity()

Returns the last velocity used in the transition

void getViewVelocity(View view, float posOnViewX, float posOnViewY, float[] returnVelocity, int type)

Returns the last layout velocity used in the transition

boolean isAttachedToWindow()

Returns true if the provided view is currently attached to a window.

boolean isInRotation()
boolean isInteractionEnabled()

Determines whether MotionLayout's touch & click handling are enabled.

boolean isViewTransitionEnabled(int viewTransitionId)

Is transition id enabled or disabled

void jumpToState(int id)

This jumps to a state It will be at that state after one repaint cycle If the current transition contains that state.

void loadLayoutDescription(int motionScene)

This overrides ConstraintLayout and only accepts a MotionScene.

boolean onInterceptTouchEvent(MotionEvent event)

Intercepts the touch event to correctly handle touch region id handover

boolean onNestedFling(View target, float velocityX, float velocityY, boolean consumed)
boolean onNestedPreFling(View target, float velocityX, float velocityY)
void onNestedPreScroll(View target, int dx, int dy, int[] consumed, int type)
void onNestedScroll(View target, int dxConsumed, int dyConsumed, int dxUnconsumed, int dyUnconsumed, int type)
void onNestedScroll(View target, int dxConsumed, int dyConsumed, int dxUnconsumed, int dyUnconsumed, int type, int[] consumed)
void onNestedScrollAccepted(View child, View target, int axes, int type)
void onRtlPropertiesChanged(int layoutDirection)
boolean onStartNestedScroll(View child, View target, int axes, int type)
void onStopNestedScroll(View target, int type)
boolean onTouchEvent(MotionEvent event)
void rebuildMotion()

This method is deprecated. Please call rebuildScene() instead.

void rebuildScene()

rebuild the motion Layouts

boolean removeTransitionListener(MotionLayout.TransitionListener listener)

adds a listener to be notified of drawer events.

void requestLayout()

void rotateTo(int id, int duration)
void scheduleTransitionTo(int id)

on completing the current transition, transition to this state.

void setInteractionEnabled(boolean enabled)

Enables (or disables) MotionLayout's onClick and onSwipe handling.

void setInterpolatedProgress(float pos)

Set the transition position between 0 an 1

void setOnHide(float progress)
void setOnShow(float progress)
void setProgress(float pos, float velocity)

Set the transition position between 0 an 1

void setProgress(float pos)

Set the transition position between 0 an 1

void setScene(MotionScene scene)

Sets a motion scene to the layout.

void setState(int id, int screenWidth, int screenHeight)

Set the State of the Constraint layout.

void setTransition(int transitionId)

Set a transition explicitly to a Transition that has an ID The transition must have been named with android:id=...

void setTransition(int beginId, int endId)

Set a transition explicitly between two constraint sets

void setTransitionDuration(int milliseconds)

Change the current Transition duration.

void setTransitionListener(MotionLayout.TransitionListener listener)

Set a listener to be notified of drawer events.

void setTransitionState(Bundle bundle)
String toString()
void touchAnimateTo(int touchUpMode, float position, float currentVelocity)
void touchSpringTo(float position, float currentVelocity)

Allows you to use trigger spring motion touch behaviour.

void transitionToEnd(Runnable onComplete)

Animate to the ending position of the current transition.

void transitionToEnd()

Animate to the ending position of the current transition.

void transitionToStart()

Animate to the starting position of the current transition.

void transitionToState(int id)

Animate to the state defined by the id.

void transitionToState(int id, int duration)

Animate to the state defined by the id.

void transitionToState(int id, int screenWidth, int screenHeight)

Animate to the state defined by the id.

void transitionToState(int id, int screenWidth, int screenHeight, int duration)

Animate to the state defined by the id.

void updateState(int stateId, ConstraintSet set)

update a ConstraintSet under the id.

void updateStateAnimate(int stateId, ConstraintSet set, int duration)

Update a ConstraintSet but animate the change.

void viewTransition(int viewTransitionId, View... view)

Execute a ViewTransition.

Protected methods

void dispatchDraw(Canvas canvas)

Used to draw debugging graphics and to do post layout changes

void fireTransitionCompleted()

This causes the callback TransitionCompleted to be called

long getNanoTime()

Subclasses can override to define testClasses

MotionLayout.MotionTracker obtainVelocityTracker()

Subclasses can override to build test frameworks

void onAttachedToWindow()
void onLayout(boolean changed, int left, int top, int right, int bottom)

void onMeasure(int widthMeasureSpec, int heightMeasureSpec)

void parseLayoutDescription(int id)

block ConstraintLayout from handling layout description

void setTransition(MotionScene.Transition transition)

Inherited methods

Constants

DEBUG_SHOW_NONE

public static final int DEBUG_SHOW_NONE

Constant Value: 0 (0x00000000)

DEBUG_SHOW_PATH

public static final int DEBUG_SHOW_PATH

Constant Value: 2 (0x00000002)

DEBUG_SHOW_PROGRESS

public static final int DEBUG_SHOW_PROGRESS

Constant Value: 1 (0x00000001)

TOUCH_UP_COMPLETE

public static final int TOUCH_UP_COMPLETE

Constant Value: 0 (0x00000000)

TOUCH_UP_COMPLETE_TO_END

public static final int TOUCH_UP_COMPLETE_TO_END

Constant Value: 2 (0x00000002)

TOUCH_UP_COMPLETE_TO_START

public static final int TOUCH_UP_COMPLETE_TO_START

Constant Value: 1 (0x00000001)

TOUCH_UP_DECELERATE

public static final int TOUCH_UP_DECELERATE

Constant Value: 4 (0x00000004)

TOUCH_UP_DECELERATE_AND_COMPLETE

public static final int TOUCH_UP_DECELERATE_AND_COMPLETE

Constant Value: 5 (0x00000005)

TOUCH_UP_NEVER_TO_END

public static final int TOUCH_UP_NEVER_TO_END

Constant Value: 7 (0x00000007)

TOUCH_UP_NEVER_TO_START

public static final int TOUCH_UP_NEVER_TO_START

Constant Value: 6 (0x00000006)

TOUCH_UP_STOP

public static final int TOUCH_UP_STOP

Constant Value: 3 (0x00000003)

VELOCITY_LAYOUT

public static final int VELOCITY_LAYOUT

Constant Value: 1 (0x00000001)

VELOCITY_POST_LAYOUT

public static final int VELOCITY_POST_LAYOUT

Constant Value: 0 (0x00000000)

VELOCITY_STATIC_LAYOUT

public static final int VELOCITY_STATIC_LAYOUT

Constant Value: 3 (0x00000003)

VELOCITY_STATIC_POST_LAYOUT

public static final int VELOCITY_STATIC_POST_LAYOUT

Constant Value: 2 (0x00000002)

Fields

IS_IN_EDIT_MODE

public static boolean IS_IN_EDIT_MODE

mMeasureDuringTransition

protected boolean mMeasureDuringTransition

Public constructors

MotionLayout

public MotionLayout (Context context)

Parameters
context Context

MotionLayout

public MotionLayout (Context context, 
                AttributeSet attrs)

Parameters
context Context

attrs AttributeSet

MotionLayout

public MotionLayout (Context context, 
                AttributeSet attrs, 
                int defStyleAttr)

Parameters
context Context

attrs AttributeSet

defStyleAttr int

Public methods

addTransitionListener

public void addTransitionListener (MotionLayout.TransitionListener listener)

adds a listener to be notified of drawer events.

Parameters
listener MotionLayout.TransitionListener: Listener to notify when drawer events occur

applyViewTransition

public boolean applyViewTransition (int viewTransitionId, 
                MotionController motionController)

Apply the view transitions keyFrames to the MotionController. Note ConstraintOverride is not used

Parameters
viewTransitionId int: the id of the view transition

motionController MotionController: the MotionController to apply the keyframes to

Returns
boolean true if it found and applied the viewTransition false otherwise

cloneConstraintSet

public ConstraintSet cloneConstraintSet (int id)

Creates a ConstraintSet based on an existing constraintSet. This makes a copy of the ConstraintSet.

Parameters
id int: The ide of the ConstraintSet

Returns
ConstraintSet the ConstraintSet

enableTransition

public void enableTransition (int transitionID, 
                boolean enable)

Parameters
transitionID int

enable boolean

enableViewTransition

public void enableViewTransition (int viewTransitionId, 
                boolean enable)

Enable a ViewTransition ID.

Parameters
viewTransitionId int: id of ViewTransition

enable boolean: If false view transition cannot be executed.

fireTrigger

public void fireTrigger (int triggerId, 
                boolean positive, 
                float progress)

This causes the callback onTransitionTrigger to be called

Parameters
triggerId int: The id set set with triggerID

positive boolean: for positive transition edge

progress float: the current progress

getConstraintSet

public ConstraintSet getConstraintSet (int id)

Get the ConstraintSet associated with an id This returns a link to the constraintset But in most cases can be used. createConstraintSet makes a copy which is more expensive.

Returns
ConstraintSet

getConstraintSetIds

public int[] getConstraintSetIds ()

Get the id's of all constraintSets used by MotionLayout

Returns
int[]

getCurrentState

public int getCurrentState ()

Return the current state id

Returns
int current state id

getDefinedTransitions

public ArrayList<MotionScene.Transition> getDefinedTransitions ()

Get all Transitions known to the system.

Returns
ArrayList<MotionScene.Transition>

getEndState

public int getEndState ()

Gets the state you are currently transition to.

Returns
int The State you are transitioning to.

getProgress

public float getProgress ()

Get current position during an animation.

Returns
float current position from 0.0 to 1.0 inclusive

getStartState

public int getStartState ()

Gets the state you are currently transitioning from. If you are transitioning from an unknown state returns -1

Returns
int State you are transitioning from.

getTargetPosition

public float getTargetPosition ()

Gets the position you are animating to typically 0 or 1. This is useful during animation after touch up

Returns
float The target position you are moving to

getTransition

public MotionScene.Transition getTransition (int id)

This returns the internal Transition Structure

Returns
MotionScene.Transition

getTransitionState

public Bundle getTransitionState ()

Returns
Bundle bundle containing start and end state

getTransitionTimeMs

public long getTransitionTimeMs ()

Gets the time of the currently set animation.

Returns
long time in Milliseconds

getVelocity

public float getVelocity ()

Returns the last velocity used in the transition

Returns
float

getViewVelocity

public void getViewVelocity (View view, 
                float posOnViewX, 
                float posOnViewY, 
                float[] returnVelocity, 
                int type)

Returns the last layout velocity used in the transition

Parameters
view View: The view

posOnViewX float: The x position on the view

posOnViewY float: The y position on the view

returnVelocity float: The velocity

type int: The type of velocity you want 0 = post layout, 1 = layout, 2 = static postlayout

isAttachedToWindow

public boolean isAttachedToWindow ()

Returns true if the provided view is currently attached to a window.

Returns
boolean

isInRotation

public boolean isInRotation ()

Returns
boolean

isInteractionEnabled

public boolean isInteractionEnabled ()

Determines whether MotionLayout's touch & click handling are enabled. An interaction enabled MotionLayout can respond to user input and initiate and control. MotionLayout interactions are enabled initially by default. MotionLayout touch & click handling may be enabled or disabled by calling its setInteractionEnabled method.

Returns
boolean true if MotionLayout's touch & click is enabled, false otherwise

isViewTransitionEnabled

public boolean isViewTransitionEnabled (int viewTransitionId)

Is transition id enabled or disabled

Parameters
viewTransitionId int: the ide of the transition

Returns
boolean true if enabled

jumpToState

public void jumpToState (int id)

This jumps to a state It will be at that state after one repaint cycle If the current transition contains that state. It setsProgress 0 or 1 to that state. If not in the current transition itsl

Parameters
id int: state to set

loadLayoutDescription

public void loadLayoutDescription (int motionScene)

This overrides ConstraintLayout and only accepts a MotionScene.

Parameters
motionScene int: The resource id, or 0 to reset the MotionScene.

onInterceptTouchEvent

public boolean onInterceptTouchEvent (MotionEvent event)

Intercepts the touch event to correctly handle touch region id handover

Returns
boolean

onNestedFling

public boolean onNestedFling (View target, 
                float velocityX, 
                float velocityY, 
                boolean consumed)

Parameters
target View

velocityX float

velocityY float

consumed boolean

Returns
boolean

onNestedPreFling

public boolean onNestedPreFling (View target, 
                float velocityX, 
                float velocityY)

Parameters
target View

velocityX float

velocityY float

Returns
boolean

onNestedPreScroll

public void onNestedPreScroll (View target, 
                int dx, 
                int dy, 
                int[] consumed, 
                int type)

Parameters
target View

dx int

dy int

consumed int

type int

onNestedScroll

public void onNestedScroll (View target, 
                int dxConsumed, 
                int dyConsumed, 
                int dxUnconsumed, 
                int dyUnconsumed, 
                int type)

Parameters
target View

dxConsumed int

dyConsumed int

dxUnconsumed int

dyUnconsumed int

type int

onNestedScroll

public void onNestedScroll (View target, 
                int dxConsumed, 
                int dyConsumed, 
                int dxUnconsumed, 
                int dyUnconsumed, 
                int type, 
                int[] consumed)

Parameters
target View

dxConsumed int

dyConsumed int

dxUnconsumed int

dyUnconsumed int

type int

consumed int

onNestedScrollAccepted

public void onNestedScrollAccepted (View child, 
                View target, 
                int axes, 
                int type)

Parameters
child View

target View

axes int

type int

onRtlPropertiesChanged

public void onRtlPropertiesChanged (int layoutDirection)

Parameters
layoutDirection int

onStartNestedScroll

public boolean onStartNestedScroll (View child, 
                View target, 
                int axes, 
                int type)

Parameters
child View

target View

axes int

type int

Returns
boolean

onStopNestedScroll

public void onStopNestedScroll (View target, 
                int type)

Parameters
target View

type int

onTouchEvent

public boolean onTouchEvent (MotionEvent event)

Parameters
event MotionEvent

Returns
boolean

rebuildMotion

public void rebuildMotion ()

This method is deprecated.
Please call rebuildScene() instead.

rebuild the motion Layouts

rebuildScene

public void rebuildScene ()

rebuild the motion Layouts

removeTransitionListener

public boolean removeTransitionListener (MotionLayout.TransitionListener listener)

adds a listener to be notified of drawer events.

Parameters
listener MotionLayout.TransitionListener: Listener to notify when drawer events occur

Returns
boolean true if it contained the specified listener

requestLayout

public void requestLayout ()

rotateTo

public void rotateTo (int id, 
                int duration)

Parameters
id int

duration int

scheduleTransitionTo

public void scheduleTransitionTo (int id)

on completing the current transition, transition to this state.

setInteractionEnabled

public void setInteractionEnabled (boolean enabled)

Enables (or disables) MotionLayout's onClick and onSwipe handling.

Parameters
enabled boolean: If true, touch & click is enabled; otherwise it is disabled

setInterpolatedProgress

public void setInterpolatedProgress (float pos)

Set the transition position between 0 an 1

setOnHide

public void setOnHide (float progress)

Parameters
progress float

setOnShow

public void setOnShow (float progress)

Parameters
progress float

setProgress

public void setProgress (float pos, 
                float velocity)

Set the transition position between 0 an 1

setProgress

public void setProgress (float pos)

Set the transition position between 0 an 1

Parameters
pos float: the position in the transition from 0...1

setScene

public void setScene (MotionScene scene)

Sets a motion scene to the layout. Subsequent calls to it will override the previous scene.

Parameters
scene MotionScene

setState

public void setState (int id, 
                int screenWidth, 
                int screenHeight)

Set the State of the Constraint layout. Causing it to load a particular ConstraintSet. for states with variants the variant with matching width and height constraintSet will be chosen

Parameters
id int: set the state width and height

setTransition

public void setTransition (int transitionId)

Set a transition explicitly to a Transition that has an ID The transition must have been named with android:id=...

Parameters
transitionId int: the id to set

setTransition

public void setTransition (int beginId, 
                int endId)

Set a transition explicitly between two constraint sets

Parameters
beginId int: the id of the start constraint set

endId int: the id of the end constraint set

setTransitionDuration

public void setTransitionDuration (int milliseconds)

Change the current Transition duration.

Parameters
milliseconds int: duration for transition to complete

setTransitionListener

public void setTransitionListener (MotionLayout.TransitionListener listener)

Set a listener to be notified of drawer events.

Parameters
listener MotionLayout.TransitionListener: Listener to notify when drawer events occur

setTransitionState

public void setTransitionState (Bundle bundle)

Parameters
bundle Bundle

Returns
void bundle containing start and end state

toString

public String toString ()

Returns
String

touchAnimateTo

public void touchAnimateTo (int touchUpMode, 
                float position, 
                float currentVelocity)

Parameters
touchUpMode int: behavior on touch up, can be either:
  • TOUCH_UP_COMPLETE (default) : will complete the transition, picking up automatically a correct velocity to do so
  • TOUCH_UP_STOP : will allow stopping mid-transition
  • TOUCH_UP_DECELERATE : will slowly decay, possibly past the transition (i.e. it will do a hard stop if unmanaged)
  • TOUCH_UP_DECELERATE_AND_COMPLETE : will automatically pick between TOUCH_UP_COMPLETE and TOUCH_UP_DECELERATE
, TOUCH_UP_STOP (will allow stopping

position float: animate to given position

touchSpringTo

public void touchSpringTo (float position, 
                float currentVelocity)

Allows you to use trigger spring motion touch behaviour. You must have configured all the spring parameters in the Transition's OnSwipe

Parameters
position float: the position 0 - 1

currentVelocity float: the current velocity rate of change in position per second

transitionToEnd

public void transitionToEnd (Runnable onComplete)

Animate to the ending position of the current transition. This will not work during on create as there is no transition Transitions are only set up during onAttach

Parameters
onComplete Runnable: callback when task is don

transitionToEnd

public void transitionToEnd ()

Animate to the ending position of the current transition. This will not work during on create as there is no transition Transitions are only set up during onAttach

transitionToStart

public void transitionToStart ()

Animate to the starting position of the current transition. This will not work during on create as there is no transition Transitions are only set up during onAttach

transitionToState

public void transitionToState (int id)

Animate to the state defined by the id. The id is the id of the ConstraintSet or the id of the State.

Parameters
id int: the state to transition to

transitionToState

public void transitionToState (int id, 
                int duration)

Animate to the state defined by the id. The id is the id of the ConstraintSet or the id of the State.

Parameters
id int: the state to transition to

duration int: time in ms. if 0 set by default or transition -1 by current

transitionToState

public void transitionToState (int id, 
                int screenWidth, 
                int screenHeight)

Animate to the state defined by the id. Width and height may be used in the picking of the id using this StateSet.

Parameters
id int: the state to transition

screenWidth int: the with of the motionLayout used to select the variant

screenHeight int: the height of the motionLayout used to select the variant

transitionToState

public void transitionToState (int id, 
                int screenWidth, 
                int screenHeight, 
                int duration)

Animate to the state defined by the id. Width and height may be used in the picking of the id using this StateSet.

Parameters
id int: the state to transition

screenWidth int: the with of the motionLayout used to select the variant

screenHeight int: the height of the motionLayout used to select the variant

duration int: time in ms. if 0 set by default or transition -1 by current

updateState

public void updateState (int stateId, 
                ConstraintSet set)

update a ConstraintSet under the id.

Parameters
stateId int: id of the ConstraintSet

set ConstraintSet: The constraintSet

updateStateAnimate

public void updateStateAnimate (int stateId, 
                ConstraintSet set, 
                int duration)

Update a ConstraintSet but animate the change.

Parameters
stateId int: id of the ConstraintSet

set ConstraintSet: The constraintSet

duration int: The length of time to perform the animation

viewTransition

public void viewTransition (int viewTransitionId, 
                View... view)

Execute a ViewTransition. Transition will execute if its conditions are met and it is enabled

Parameters
view View: The views to apply to

Protected methods

dispatchDraw

protected void dispatchDraw (Canvas canvas)

Used to draw debugging graphics and to do post layout changes

fireTransitionCompleted

protected void fireTransitionCompleted ()

This causes the callback TransitionCompleted to be called

getNanoTime

protected long getNanoTime ()

Subclasses can override to define testClasses

Returns
long

obtainVelocityTracker

protected MotionLayout.MotionTracker obtainVelocityTracker ()

Subclasses can override to build test frameworks

Returns
MotionLayout.MotionTracker

onAttachedToWindow

protected void onAttachedToWindow ()

onLayout

protected void onLayout (boolean changed, 
                int left, 
                int top, 
                int right, 
                int bottom)

Parameters
changed boolean

left int

top int

right int

bottom int

onMeasure

protected void onMeasure (int widthMeasureSpec, 
                int heightMeasureSpec)

Parameters
widthMeasureSpec int

heightMeasureSpec int

parseLayoutDescription

protected void parseLayoutDescription (int id)

block ConstraintLayout from handling layout description

setTransition

protected void setTransition (MotionScene.Transition transition)

Parameters
transition MotionScene.Transition