FileDocCategorySizeDatePackage
SwipeRefreshLayout.javaAPI DocAndroid 5.1 API37115Thu Mar 12 22:22:56 GMT 2015android.support.v4.widget

SwipeRefreshLayout

public class SwipeRefreshLayout extends android.view.ViewGroup
The SwipeRefreshLayout should be used whenever the user can refresh the contents of a view via a vertical swipe gesture. The activity that instantiates this view should add an OnRefreshListener to be notified whenever the swipe to refresh gesture is completed. The SwipeRefreshLayout will notify the listener each and every time the gesture is completed again; the listener is responsible for correctly determining when to actually initiate a refresh of its content. If the listener determines there should not be a refresh, it must call setRefreshing(false) to cancel any visual indication of a refresh. If an activity wishes to show just the progress animation, it should call setRefreshing(true). To disable the gesture and progress animation, call setEnabled(false) on the view.

This layout should be made the parent of the view that will be refreshed as a result of the gesture and can only support one direct child. This view will also be made the target of the gesture and will be forced to match both the width and the height supplied in this layout. The SwipeRefreshLayout does not provide accessibility events; instead, a menu item must be provided to allow refresh of the content wherever this gesture is used.

Fields Summary
public static final int
LARGE
public static final int
DEFAULT
private static final String
LOG_TAG
private static final int
MAX_ALPHA
private static final int
STARTING_PROGRESS_ALPHA
private static final int
CIRCLE_DIAMETER
private static final int
CIRCLE_DIAMETER_LARGE
private static final float
DECELERATE_INTERPOLATION_FACTOR
private static final int
INVALID_POINTER
private static final float
DRAG_RATE
private static final float
MAX_PROGRESS_ANGLE
private static final int
SCALE_DOWN_DURATION
private static final int
ALPHA_ANIMATION_DURATION
private static final int
ANIMATE_TO_TRIGGER_DURATION
private static final int
ANIMATE_TO_START_DURATION
private static final int
CIRCLE_BG_LIGHT
private static final int
DEFAULT_CIRCLE_TARGET
private android.view.View
mTarget
private OnRefreshListener
mListener
private boolean
mRefreshing
private int
mTouchSlop
private float
mTotalDragDistance
private int
mMediumAnimationDuration
private int
mCurrentTargetOffsetTop
private boolean
mOriginalOffsetCalculated
private float
mInitialMotionY
private float
mInitialDownY
private boolean
mIsBeingDragged
private int
mActivePointerId
private boolean
mScale
private boolean
mReturningToStart
private final android.view.animation.DecelerateInterpolator
mDecelerateInterpolator
private static final int[]
LAYOUT_ATTRS
private CircleImageView
mCircleView
private int
mCircleViewIndex
protected int
mFrom
private float
mStartingScale
protected int
mOriginalOffsetTop
private MaterialProgressDrawable
mProgress
private android.view.animation.Animation
mScaleAnimation
private android.view.animation.Animation
mScaleDownAnimation
private android.view.animation.Animation
mAlphaStartAnimation
private android.view.animation.Animation
mAlphaMaxAnimation
private android.view.animation.Animation
mScaleDownToStartAnimation
private float
mSpinnerFinalOffset
private boolean
mNotify
private int
mCircleWidth
private int
mCircleHeight
private boolean
mUsingCustomStart
private android.view.animation.Animation.AnimationListener
mRefreshListener
private final android.view.animation.Animation
mAnimateToCorrectPosition
private final android.view.animation.Animation
mAnimateToStartPosition
Constructors Summary
public SwipeRefreshLayout(android.content.Context context)
Simple constructor to use when creating a SwipeRefreshLayout from code.

param
context

        this(context, null);
public SwipeRefreshLayout(android.content.Context context, android.util.AttributeSet attrs)
Constructor that is called when inflating SwipeRefreshLayout from XML.

param
context
param
attrs

        super(context, attrs);

        mTouchSlop = ViewConfiguration.get(context).getScaledTouchSlop();

        mMediumAnimationDuration = getResources().getInteger(
                android.R.integer.config_mediumAnimTime);

        setWillNotDraw(false);
        mDecelerateInterpolator = new DecelerateInterpolator(DECELERATE_INTERPOLATION_FACTOR);

        final TypedArray a = context.obtainStyledAttributes(attrs, LAYOUT_ATTRS);
        setEnabled(a.getBoolean(0, true));
        a.recycle();

        final DisplayMetrics metrics = getResources().getDisplayMetrics();
        mCircleWidth = (int) (CIRCLE_DIAMETER * metrics.density);
        mCircleHeight = (int) (CIRCLE_DIAMETER * metrics.density);

        createProgressView();
        ViewCompat.setChildrenDrawingOrderEnabled(this, true);
        // the absolute offset has to take into account that the circle starts at an offset
        mSpinnerFinalOffset = DEFAULT_CIRCLE_TARGET * metrics.density;
        mTotalDragDistance = mSpinnerFinalOffset;
Methods Summary
private voidanimateOffsetToCorrectPosition(int from, android.view.animation.Animation.AnimationListener listener)

        mFrom = from;
        mAnimateToCorrectPosition.reset();
        mAnimateToCorrectPosition.setDuration(ANIMATE_TO_TRIGGER_DURATION);
        mAnimateToCorrectPosition.setInterpolator(mDecelerateInterpolator);
        if (listener != null) {
            mCircleView.setAnimationListener(listener);
        }
        mCircleView.clearAnimation();
        mCircleView.startAnimation(mAnimateToCorrectPosition);
private voidanimateOffsetToStartPosition(int from, android.view.animation.Animation.AnimationListener listener)

        if (mScale) {
            // Scale the item back down
            startScaleDownReturnToStartAnimation(from, listener);
        } else {
            mFrom = from;
            mAnimateToStartPosition.reset();
            mAnimateToStartPosition.setDuration(ANIMATE_TO_START_DURATION);
            mAnimateToStartPosition.setInterpolator(mDecelerateInterpolator);
            if (listener != null) {
                mCircleView.setAnimationListener(listener);
            }
            mCircleView.clearAnimation();
            mCircleView.startAnimation(mAnimateToStartPosition);
        }
public booleancanChildScrollUp()

return
Whether it is possible for the child view of this layout to scroll up. Override this if the child view is a custom view.

        if (android.os.Build.VERSION.SDK_INT < 14) {
            if (mTarget instanceof AbsListView) {
                final AbsListView absListView = (AbsListView) mTarget;
                return absListView.getChildCount() > 0
                        && (absListView.getFirstVisiblePosition() > 0 || absListView.getChildAt(0)
                                .getTop() < absListView.getPaddingTop());
            } else {
                return mTarget.getScrollY() > 0;
            }
        } else {
            return ViewCompat.canScrollVertically(mTarget, -1);
        }
private voidcreateProgressView()

        mCircleView = new CircleImageView(getContext(), CIRCLE_BG_LIGHT, CIRCLE_DIAMETER/2);
        mProgress = new MaterialProgressDrawable(getContext(), this);
        mProgress.setBackgroundColor(CIRCLE_BG_LIGHT);
        mCircleView.setImageDrawable(mProgress);
        mCircleView.setVisibility(View.GONE);
        addView(mCircleView);
private voidensureTarget()

        // Don't bother getting the parent height if the parent hasn't been laid
        // out yet.
        if (mTarget == null) {
            for (int i = 0; i < getChildCount(); i++) {
                View child = getChildAt(i);
                if (!child.equals(mCircleView)) {
                    mTarget = child;
                    break;
                }
            }
        }
protected intgetChildDrawingOrder(int childCount, int i)

        if (mCircleViewIndex < 0) {
            return i;
        } else if (i == childCount - 1) {
            // Draw the selected child last
            return mCircleViewIndex;
        } else if (i >= mCircleViewIndex) {
            // Move the children after the selected child earlier one
            return i + 1;
        } else {
            // Keep the children before the selected child the same
            return i;
        }
private floatgetMotionEventY(android.view.MotionEvent ev, int activePointerId)

        final int index = MotionEventCompat.findPointerIndex(ev, activePointerId);
        if (index < 0) {
            return -1;
        }
        return MotionEventCompat.getY(ev, index);
public intgetProgressCircleDiameter()
Get the diameter of the progress circle that is displayed as part of the swipe to refresh layout. This is not valid until a measure pass has completed.

return
Diameter in pixels of the progress circle view.

        return mCircleView != null ?mCircleView.getMeasuredHeight() : 0;
private booleanisAlphaUsedForScale()
Pre API 11, alpha is used to make the progress circle appear instead of scale.

        return android.os.Build.VERSION.SDK_INT < 11;
private booleanisAnimationRunning(android.view.animation.Animation animation)

        return animation != null && animation.hasStarted() && !animation.hasEnded();
public booleanisRefreshing()

return
Whether the SwipeRefreshWidget is actively showing refresh progress.

        return mRefreshing;
private voidmoveToStart(float interpolatedTime)


        
        int targetTop = 0;
        targetTop = (mFrom + (int) ((mOriginalOffsetTop - mFrom) * interpolatedTime));
        int offset = targetTop - mCircleView.getTop();
        setTargetOffsetTopAndBottom(offset, false /* requires update */);
public booleanonInterceptTouchEvent(android.view.MotionEvent ev)

        ensureTarget();

        final int action = MotionEventCompat.getActionMasked(ev);

        if (mReturningToStart && action == MotionEvent.ACTION_DOWN) {
            mReturningToStart = false;
        }

        if (!isEnabled() || mReturningToStart || canChildScrollUp() || mRefreshing) {
            // Fail fast if we're not in a state where a swipe is possible
            return false;
        }

        switch (action) {
            case MotionEvent.ACTION_DOWN:
                setTargetOffsetTopAndBottom(mOriginalOffsetTop - mCircleView.getTop(), true);
                mActivePointerId = MotionEventCompat.getPointerId(ev, 0);
                mIsBeingDragged = false;
                final float initialDownY = getMotionEventY(ev, mActivePointerId);
                if (initialDownY == -1) {
                    return false;
                }
                mInitialDownY = initialDownY;
                break;

            case MotionEvent.ACTION_MOVE:
                if (mActivePointerId == INVALID_POINTER) {
                    Log.e(LOG_TAG, "Got ACTION_MOVE event but don't have an active pointer id.");
                    return false;
                }

                final float y = getMotionEventY(ev, mActivePointerId);
                if (y == -1) {
                    return false;
                }
                final float yDiff = y - mInitialDownY;
                if (yDiff > mTouchSlop && !mIsBeingDragged) {
                    mInitialMotionY = mInitialDownY + mTouchSlop;
                    mIsBeingDragged = true;
                    mProgress.setAlpha(STARTING_PROGRESS_ALPHA);
                }
                break;

            case MotionEventCompat.ACTION_POINTER_UP:
                onSecondaryPointerUp(ev);
                break;

            case MotionEvent.ACTION_UP:
            case MotionEvent.ACTION_CANCEL:
                mIsBeingDragged = false;
                mActivePointerId = INVALID_POINTER;
                break;
        }

        return mIsBeingDragged;
protected voidonLayout(boolean changed, int left, int top, int right, int bottom)

        final int width = getMeasuredWidth();
        final int height = getMeasuredHeight();
        if (getChildCount() == 0) {
            return;
        }
        if (mTarget == null) {
            ensureTarget();
        }
        if (mTarget == null) {
            return;
        }
        final View child = mTarget;
        final int childLeft = getPaddingLeft();
        final int childTop = getPaddingTop();
        final int childWidth = width - getPaddingLeft() - getPaddingRight();
        final int childHeight = height - getPaddingTop() - getPaddingBottom();
        child.layout(childLeft, childTop, childLeft + childWidth, childTop + childHeight);
        int circleWidth = mCircleView.getMeasuredWidth();
        int circleHeight = mCircleView.getMeasuredHeight();
        mCircleView.layout((width / 2 - circleWidth / 2), mCurrentTargetOffsetTop,
                (width / 2 + circleWidth / 2), mCurrentTargetOffsetTop + circleHeight);
public voidonMeasure(int widthMeasureSpec, int heightMeasureSpec)

        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
        if (mTarget == null) {
            ensureTarget();
        }
        if (mTarget == null) {
            return;
        }
        mTarget.measure(MeasureSpec.makeMeasureSpec(
                getMeasuredWidth() - getPaddingLeft() - getPaddingRight(),
                MeasureSpec.EXACTLY), MeasureSpec.makeMeasureSpec(
                getMeasuredHeight() - getPaddingTop() - getPaddingBottom(), MeasureSpec.EXACTLY));
        mCircleView.measure(MeasureSpec.makeMeasureSpec(mCircleWidth, MeasureSpec.EXACTLY),
                MeasureSpec.makeMeasureSpec(mCircleHeight, MeasureSpec.EXACTLY));
        if (!mUsingCustomStart && !mOriginalOffsetCalculated) {
            mOriginalOffsetCalculated = true;
            mCurrentTargetOffsetTop = mOriginalOffsetTop = -mCircleView.getMeasuredHeight();
        }
        mCircleViewIndex = -1;
        // Get the index of the circleview.
        for (int index = 0; index < getChildCount(); index++) {
            if (getChildAt(index) == mCircleView) {
                mCircleViewIndex = index;
                break;
            }
        }
private voidonSecondaryPointerUp(android.view.MotionEvent ev)

        final int pointerIndex = MotionEventCompat.getActionIndex(ev);
        final int pointerId = MotionEventCompat.getPointerId(ev, pointerIndex);
        if (pointerId == mActivePointerId) {
            // This was our active pointer going up. Choose a new
            // active pointer and adjust accordingly.
            final int newPointerIndex = pointerIndex == 0 ? 1 : 0;
            mActivePointerId = MotionEventCompat.getPointerId(ev, newPointerIndex);
        }
public booleanonTouchEvent(android.view.MotionEvent ev)

        final int action = MotionEventCompat.getActionMasked(ev);

        if (mReturningToStart && action == MotionEvent.ACTION_DOWN) {
            mReturningToStart = false;
        }

        if (!isEnabled() || mReturningToStart || canChildScrollUp()) {
            // Fail fast if we're not in a state where a swipe is possible
            return false;
        }

        switch (action) {
            case MotionEvent.ACTION_DOWN:
                mActivePointerId = MotionEventCompat.getPointerId(ev, 0);
                mIsBeingDragged = false;
                break;

            case MotionEvent.ACTION_MOVE: {
                final int pointerIndex = MotionEventCompat.findPointerIndex(ev, mActivePointerId);
                if (pointerIndex < 0) {
                    Log.e(LOG_TAG, "Got ACTION_MOVE event but have an invalid active pointer id.");
                    return false;
                }

                final float y = MotionEventCompat.getY(ev, pointerIndex);
                final float overscrollTop = (y - mInitialMotionY) * DRAG_RATE;
                if (mIsBeingDragged) {
                    mProgress.showArrow(true);
                    float originalDragPercent = overscrollTop / mTotalDragDistance;
                    if (originalDragPercent < 0) {
                        return false;
                    }
                    float dragPercent = Math.min(1f, Math.abs(originalDragPercent));
                    float adjustedPercent = (float) Math.max(dragPercent - .4, 0) * 5 / 3;
                    float extraOS = Math.abs(overscrollTop) - mTotalDragDistance;
                    float slingshotDist = mUsingCustomStart ? mSpinnerFinalOffset
                            - mOriginalOffsetTop : mSpinnerFinalOffset;
                    float tensionSlingshotPercent = Math.max(0,
                            Math.min(extraOS, slingshotDist * 2) / slingshotDist);
                    float tensionPercent = (float) ((tensionSlingshotPercent / 4) - Math.pow(
                            (tensionSlingshotPercent / 4), 2)) * 2f;
                    float extraMove = (slingshotDist) * tensionPercent * 2;

                    int targetY = mOriginalOffsetTop
                            + (int) ((slingshotDist * dragPercent) + extraMove);
                    // where 1.0f is a full circle
                    if (mCircleView.getVisibility() != View.VISIBLE) {
                        mCircleView.setVisibility(View.VISIBLE);
                    }
                    if (!mScale) {
                        ViewCompat.setScaleX(mCircleView, 1f);
                        ViewCompat.setScaleY(mCircleView, 1f);
                    }
                    if (overscrollTop < mTotalDragDistance) {
                        if (mScale) {
                            setAnimationProgress(overscrollTop / mTotalDragDistance);
                        }
                        if (mProgress.getAlpha() > STARTING_PROGRESS_ALPHA
                                && !isAnimationRunning(mAlphaStartAnimation)) {
                            // Animate the alpha
                            startProgressAlphaStartAnimation();
                        }
                        float strokeStart = adjustedPercent * .8f;
                        mProgress.setStartEndTrim(0f, Math.min(MAX_PROGRESS_ANGLE, strokeStart));
                        mProgress.setArrowScale(Math.min(1f, adjustedPercent));
                    } else {
                        if (mProgress.getAlpha() < MAX_ALPHA
                                && !isAnimationRunning(mAlphaMaxAnimation)) {
                            // Animate the alpha
                            startProgressAlphaMaxAnimation();
                        }
                    }
                    float rotation = (-0.25f + .4f * adjustedPercent + tensionPercent * 2) * .5f;
                    mProgress.setProgressRotation(rotation);
                    setTargetOffsetTopAndBottom(targetY - mCurrentTargetOffsetTop,
                            true /* requires update */);
                }
                break;
            }
            case MotionEventCompat.ACTION_POINTER_DOWN: {
                final int index = MotionEventCompat.getActionIndex(ev);
                mActivePointerId = MotionEventCompat.getPointerId(ev, index);
                break;
            }

            case MotionEventCompat.ACTION_POINTER_UP:
                onSecondaryPointerUp(ev);
                break;

            case MotionEvent.ACTION_UP:
            case MotionEvent.ACTION_CANCEL: {
                if (mActivePointerId == INVALID_POINTER) {
                    if (action == MotionEvent.ACTION_UP) {
                        Log.e(LOG_TAG, "Got ACTION_UP event but don't have an active pointer id.");
                    }
                    return false;
                }
                final int pointerIndex = MotionEventCompat.findPointerIndex(ev, mActivePointerId);
                final float y = MotionEventCompat.getY(ev, pointerIndex);
                final float overscrollTop = (y - mInitialMotionY) * DRAG_RATE;
                mIsBeingDragged = false;
                if (overscrollTop > mTotalDragDistance) {
                    setRefreshing(true, true /* notify */);
                } else {
                    // cancel refresh
                    mRefreshing = false;
                    mProgress.setStartEndTrim(0f, 0f);
                    Animation.AnimationListener listener = null;
                    if (!mScale) {
                        listener = new Animation.AnimationListener() {

                            @Override
                            public void onAnimationStart(Animation animation) {
                            }

                            @Override
                            public void onAnimationEnd(Animation animation) {
                                if (!mScale) {
                                    startScaleDownAnimation(null);
                                }
                            }

                            @Override
                            public void onAnimationRepeat(Animation animation) {
                            }

                        };
                    }
                    animateOffsetToStartPosition(mCurrentTargetOffsetTop, listener);
                    mProgress.showArrow(false);
                }
                mActivePointerId = INVALID_POINTER;
                return false;
            }
        }

        return true;
public voidrequestDisallowInterceptTouchEvent(boolean b)

        // Nope.
private voidsetAnimationProgress(float progress)
Pre API 11, this does an alpha animation.

param
progress

        if (isAlphaUsedForScale()) {
            setColorViewAlpha((int) (progress * MAX_ALPHA));
        } else {
            ViewCompat.setScaleX(mCircleView, progress);
            ViewCompat.setScaleY(mCircleView, progress);
        }
public voidsetColorScheme(int colors)

deprecated
Use {@link #setColorSchemeResources(int...)}

        setColorSchemeResources(colors);
public voidsetColorSchemeColors(int colors)
Set the colors used in the progress animation. The first color will also be the color of the bar that grows in response to a user swipe gesture.

param
colors

        ensureTarget();
        mProgress.setColorSchemeColors(colors);
public voidsetColorSchemeResources(int colorResIds)
Set the color resources used in the progress animation from color resources. The first color will also be the color of the bar that grows in response to a user swipe gesture.

param
colorResIds

        final Resources res = getResources();
        int[] colorRes = new int[colorResIds.length];
        for (int i = 0; i < colorResIds.length; i++) {
            colorRes[i] = res.getColor(colorResIds[i]);
        }
        setColorSchemeColors(colorRes);
private voidsetColorViewAlpha(int targetAlpha)


        
        mCircleView.getBackground().setAlpha(targetAlpha);
        mProgress.setAlpha(targetAlpha);
public voidsetDistanceToTriggerSync(int distance)
Set the distance to trigger a sync in dips

param
distance

        mTotalDragDistance = distance;
public voidsetOnRefreshListener(android.support.v4.widget.SwipeRefreshLayout$OnRefreshListener listener)
Set the listener to be notified when a refresh is triggered via the swipe gesture.

        mListener = listener;
public voidsetProgressBackgroundColor(int colorRes)

deprecated
Use {@link #setProgressBackgroundColorSchemeResource(int)}

        setProgressBackgroundColorSchemeResource(colorRes);
public voidsetProgressBackgroundColorSchemeColor(int color)
Set the background color of the progress spinner disc.

param
color

        mCircleView.setBackgroundColor(color);
        mProgress.setBackgroundColor(color);
public voidsetProgressBackgroundColorSchemeResource(int colorRes)
Set the background color of the progress spinner disc.

param
colorRes Resource id of the color.

        setProgressBackgroundColorSchemeColor(getResources().getColor(colorRes));
public voidsetProgressViewEndTarget(boolean scale, int end)
The refresh indicator resting position is always positioned near the top of the refreshing content. This position is a consistent location, but can be adjusted in either direction based on whether or not there is a toolbar or actionbar present.

param
scale Set to true if there is no view at a higher z-order than where the progress spinner is set to appear.
param
end The offset in pixels from the top of this view at which the progress spinner should come to rest after a successful swipe gesture.

        mSpinnerFinalOffset = end;
        mScale = scale;
        mCircleView.invalidate();
public voidsetProgressViewOffset(boolean scale, int start, int end)
The refresh indicator starting and resting position is always positioned near the top of the refreshing content. This position is a consistent location, but can be adjusted in either direction based on whether or not there is a toolbar or actionbar present.

param
scale Set to true if there is no view at a higher z-order than where the progress spinner is set to appear.
param
start The offset in pixels from the top of this view at which the progress spinner should appear.
param
end The offset in pixels from the top of this view at which the progress spinner should come to rest after a successful swipe gesture.

        mScale = scale;
        mCircleView.setVisibility(View.GONE);
        mOriginalOffsetTop = mCurrentTargetOffsetTop = start;
        mSpinnerFinalOffset = end;
        mUsingCustomStart = true;
        mCircleView.invalidate();
public voidsetRefreshing(boolean refreshing)
Notify the widget that refresh state has changed. Do not call this when refresh is triggered by a swipe gesture.

param
refreshing Whether or not the view should show refresh progress.

        if (refreshing && mRefreshing != refreshing) {
            // scale and show
            mRefreshing = refreshing;
            int endTarget = 0;
            if (!mUsingCustomStart) {
                endTarget = (int) (mSpinnerFinalOffset + mOriginalOffsetTop);
            } else {
                endTarget = (int) mSpinnerFinalOffset;
            }
            setTargetOffsetTopAndBottom(endTarget - mCurrentTargetOffsetTop,
                    true /* requires update */);
            mNotify = false;
            startScaleUpAnimation(mRefreshListener);
        } else {
            setRefreshing(refreshing, false /* notify */);
        }
private voidsetRefreshing(boolean refreshing, boolean notify)

        if (mRefreshing != refreshing) {
            mNotify = notify;
            ensureTarget();
            mRefreshing = refreshing;
            if (mRefreshing) {
                animateOffsetToCorrectPosition(mCurrentTargetOffsetTop, mRefreshListener);
            } else {
                startScaleDownAnimation(mRefreshListener);
            }
        }
public voidsetSize(int size)
One of DEFAULT, or LARGE.

        if (size != MaterialProgressDrawable.LARGE && size != MaterialProgressDrawable.DEFAULT) {
            return;
        }
        final DisplayMetrics metrics = getResources().getDisplayMetrics();
        if (size == MaterialProgressDrawable.LARGE) {
            mCircleHeight = mCircleWidth = (int) (CIRCLE_DIAMETER_LARGE * metrics.density);
        } else {
            mCircleHeight = mCircleWidth = (int) (CIRCLE_DIAMETER * metrics.density);
        }
        // force the bounds of the progress circle inside the circle view to
        // update by setting it to null before updating its size and then
        // re-setting it
        mCircleView.setImageDrawable(null);
        mProgress.updateSizes(size);
        mCircleView.setImageDrawable(mProgress);
private voidsetTargetOffsetTopAndBottom(int offset, boolean requiresUpdate)

        mCircleView.bringToFront();
        mCircleView.offsetTopAndBottom(offset);
        mCurrentTargetOffsetTop = mCircleView.getTop();
        if (requiresUpdate && android.os.Build.VERSION.SDK_INT < 11) {
            invalidate();
        }
private android.view.animation.AnimationstartAlphaAnimation(int startingAlpha, int endingAlpha)

        // Pre API 11, alpha is used in place of scale. Don't also use it to
        // show the trigger point.
        if (mScale && isAlphaUsedForScale()) {
            return null;
        }
        Animation alpha = new Animation() {
            @Override
            public void applyTransformation(float interpolatedTime, Transformation t) {
                mProgress
                        .setAlpha((int) (startingAlpha+ ((endingAlpha - startingAlpha)
                                * interpolatedTime)));
            }
        };
        alpha.setDuration(ALPHA_ANIMATION_DURATION);
        // Clear out the previous animation listeners.
        mCircleView.setAnimationListener(null);
        mCircleView.clearAnimation();
        mCircleView.startAnimation(alpha);
        return alpha;
private voidstartProgressAlphaMaxAnimation()

        mAlphaMaxAnimation = startAlphaAnimation(mProgress.getAlpha(), MAX_ALPHA);
private voidstartProgressAlphaStartAnimation()

        mAlphaStartAnimation = startAlphaAnimation(mProgress.getAlpha(), STARTING_PROGRESS_ALPHA);
private voidstartScaleDownAnimation(android.view.animation.Animation.AnimationListener listener)

        mScaleDownAnimation = new Animation() {
            @Override
            public void applyTransformation(float interpolatedTime, Transformation t) {
                setAnimationProgress(1 - interpolatedTime);
            }
        };
        mScaleDownAnimation.setDuration(SCALE_DOWN_DURATION);
        mCircleView.setAnimationListener(listener);
        mCircleView.clearAnimation();
        mCircleView.startAnimation(mScaleDownAnimation);
private voidstartScaleDownReturnToStartAnimation(int from, android.view.animation.Animation.AnimationListener listener)


       
              
        mFrom = from;
        if (isAlphaUsedForScale()) {
            mStartingScale = mProgress.getAlpha();
        } else {
            mStartingScale = ViewCompat.getScaleX(mCircleView);
        }
        mScaleDownToStartAnimation = new Animation() {
            @Override
            public void applyTransformation(float interpolatedTime, Transformation t) {
                float targetScale = (mStartingScale + (-mStartingScale  * interpolatedTime));
                setAnimationProgress(targetScale);
                moveToStart(interpolatedTime);
            }
        };
        mScaleDownToStartAnimation.setDuration(SCALE_DOWN_DURATION);
        if (listener != null) {
            mCircleView.setAnimationListener(listener);
        }
        mCircleView.clearAnimation();
        mCircleView.startAnimation(mScaleDownToStartAnimation);
private voidstartScaleUpAnimation(android.view.animation.Animation.AnimationListener listener)

        mCircleView.setVisibility(View.VISIBLE);
        if (android.os.Build.VERSION.SDK_INT >= 11) {
            // Pre API 11, alpha is used in place of scale up to show the
            // progress circle appearing.
            // Don't adjust the alpha during appearance otherwise.
            mProgress.setAlpha(MAX_ALPHA);
        }
        mScaleAnimation = new Animation() {
            @Override
            public void applyTransformation(float interpolatedTime, Transformation t) {
                setAnimationProgress(interpolatedTime);
            }
        };
        mScaleAnimation.setDuration(mMediumAnimationDuration);
        if (listener != null) {
            mCircleView.setAnimationListener(listener);
        }
        mCircleView.clearAnimation();
        mCircleView.startAnimation(mScaleAnimation);