Package androidx.constraintlayout.core.motion

Class Motion

  • All Implemented Interfaces:
    TypedValues
    public class Motion
extends java.lang.Object
implements TypedValues
    This contains the picture of a view through the a transition and is used to interpolate it During an transition every view has a MotionController which drives its position.

    All parameter which affect a views motion are added to MotionController and then setup() builds out the splines that control the view.

    • Method Detail

      • getTransformPivotTarget

        public int getTransformPivotTarget()
        Get the view to pivot around
        Returns:
        id of view or UNSET if not set

      • setTransformPivotTarget

        public void setTransformPivotTarget​(int transformPivotTarget)
        Set a view to pivot around
        Parameters:
        transformPivotTarget - id of view

      • getKeyFrame

        public MotionPaths getKeyFrame​(int i)
        provides access to MotionPath objects

      • getStartX

        public float getStartX()
        get the left most position of the widget at the start of the movement.
        Returns:
        the left most position

      • getStartY

        public float getStartY()
        get the top most position of the widget at the start of the movement. Positive is down.
        Returns:
        the top most position

      • getFinalX

        public float getFinalX()
        get the left most position of the widget at the end of the movement.
        Returns:
        the left most position

      • getFinalY

        public float getFinalY()
        get the top most position of the widget at the end of the movement. Positive is down.
        Returns:
        the top most position

      • getStartWidth

        public float getStartWidth()
        get the width of the widget at the start of the movement.
        Returns:
        the width at the start

      • getStartHeight

        public float getStartHeight()
        get the width of the widget at the start of the movement.
        Returns:
        the height at the start

      • getFinalWidth

        public float getFinalWidth()
        get the width of the widget at the end of the movement.
        Returns:
        the width at the end

      • getFinalHeight

        public float getFinalHeight()
        get the width of the widget at the end of the movement.
        Returns:
        the height at the end

      • getAnimateRelativeTo

        public int getAnimateRelativeTo()
        Will return the id of the view to move relative to The position at the start and then end will be viewed relative to this view -1 is the return value if NOT in polar mode
        Returns:
        the view id of the view this is in polar mode to or -1 if not in polar

      • setupRelative

        public void setupRelative​(Motion motionController)

      • getCenterX

        public float getCenterX()

      • getCenterY

        public float getCenterY()

      • getCenter

        public void getCenter​(double p,
                      float[] pos,
                      float[] vel)

      • buildPath

        public void buildPath​(float[] points,
                      int pointCount)
        fill the array point with the center coordinates point[0] is filled with the x coordinate of "time" 0.0 mPoints[point.length-1] is filled with the y coordinate of "time" 1.0
        Parameters:
        points - array to fill (should be 2x the number of mPoints

      • buildKeyFrames

        public int buildKeyFrames​(float[] keyFrames,
                          int[] mode,
                          int[] pos)

      • buildRect

        public void buildRect​(float p,
                      float[] path,
                      int offset)

      • addKey

        public void addKey​(MotionKey key)

      • setPathMotionArc

        public void setPathMotionArc​(int arc)

      • setup

        public void setup​(int parentWidth,
                  int parentHeight,
                  float transitionDuration,
                  long currentTime)
        Called after all TimePoints & Cycles have been added; Spines are evaluated

      • toString

        public java.lang.String toString()
        Debug string
        Overrides:
        toString in class java.lang.Object

      • setStartState

        public void setStartState​(ViewState rect,
                          MotionWidget v,
                          int rotation,
                          int preWidth,
                          int preHeight)

      • interpolate

        public boolean interpolate​(MotionWidget child,
                           float globalPosition,
                           long time,
                           KeyCache keyCache)
        The main driver of interpolation
        Returns:
        do you need to keep animating

      • getDpDt

        public void getDpDt​(float position,
                    float locationX,
                    float locationY,
                    float[] mAnchorDpDt)
        This returns the differential with respect to the animation layout position (Progress) of a point on the view (post layout effects are not computed)
        Parameters:
        position - position in time
        locationX - the x location on the view (0 = left edge, 1 = right edge)
        locationY - the y location on the view (0 = top, 1 = bottom)
        mAnchorDpDt - returns the differential of the motion with respect to the position

      • getDrawPath

        public int getDrawPath()

      • setDrawPath

        public void setDrawPath​(int debugMode)

      • getKeyFramePositions

        public int getKeyFramePositions​(int[] type,
                                float[] pos)
        Get the keyFrames for the view controlled by this MotionController
        Parameters:
        type - is position(0-100) + 1000 * mType(1=Attributes, 2=Position, 3=TimeCycle 4=Cycle 5=Trigger
        pos - the x&y position of the keyFrame along the path
        Returns:
        Number of keyFrames found

      • getKeyFrameInfo

        public int getKeyFrameInfo​(int type,
                           int[] info)
        Get the keyFrames for the view controlled by this MotionController the info data structure is of the form 0 length if your are at index i the [i+len+1] is the next entry 1 type 1=Attributes, 2=Position, 3=TimeCycle 4=Cycle 5=Trigger 2 position 3 x location 4 y location 5 ... length
        Parameters:
        info - is a data structure array of int that holds info on each keyframe
        Returns:
        Number of keyFrames found

      • setValue

        public boolean setValue​(int id,
                        int value)
        Description copied from interface: TypedValues
        Used to set integer values
        Specified by:
        setValue in interface TypedValues
        Returns:
        true if it accepted the value

      • setValue

        public boolean setValue​(int id,
                        float value)
        Description copied from interface: TypedValues
        Used to set float values
        Specified by:
        setValue in interface TypedValues
        Returns:
        true if it accepted the value

      • setValue

        public boolean setValue​(int id,
                        java.lang.String value)
        Description copied from interface: TypedValues
        Used to set String values
        Specified by:
        setValue in interface TypedValues
        Returns:
        true if it accepted the value

      • setValue

        public boolean setValue​(int id,
                        boolean value)
        Description copied from interface: TypedValues
        Used to set boolean values
        Specified by:
        setValue in interface TypedValues
        Returns:
        true if it accepted the value

      • getId

        public int getId​(java.lang.String name)
        Specified by:
        getId in interface TypedValues

      • setStaggerScale

        public void setStaggerScale​(float staggerScale)
        Set stagger scale

      • setStaggerOffset

        public void setStaggerOffset​(float staggerOffset)
        set the offset used in calculating stagger launches
        Parameters:
        staggerOffset - fraction of progress before this controller runs

      • getMotionStagger

        public float getMotionStagger()
        The values set in motion: { stagger: '2' }
        Returns:
        value from motion: { stagger: ? } or NaN if not set