bhav.swipeaction.SwipeAction.java Source code

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/*
 *              Apache License
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package bhav.swipeaction;

import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.drawable.Drawable;
import android.graphics.drawable.shapes.Shape;
import android.support.annotation.ColorInt;
import android.support.annotation.ColorRes;
import android.support.v4.view.MotionEventCompat;
import android.support.v4.view.NestedScrollingChild;
import android.support.v4.view.NestedScrollingChildHelper;
import android.support.v4.view.NestedScrollingParent;
import android.support.v4.view.NestedScrollingParentHelper;
import android.support.v4.view.ViewCompat;
import android.util.AttributeSet;
import android.util.DisplayMetrics;
import android.util.Log;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewConfiguration;
import android.view.ViewGroup;
import android.view.animation.Animation;
import android.view.animation.Animation.AnimationListener;
import android.view.animation.DecelerateInterpolator;
import android.view.animation.Transformation;
import android.widget.AbsListView;

/**
 * Swipe Down for action.
 */
public class SwipeAction extends ViewGroup implements NestedScrollingParent, NestedScrollingChild {

    private static final String TAG = SwipeAction.class.getSimpleName();

    private final static int DEF_PADDING_BOTTOM = 24;
    private final static int DEF_PADDING_TOP = 24;
    private final static int DEF_PADDING_START = 24;
    private final static int DEF_PADDING_END = 24;
    private static final int MAX_ALPHA = 255;
    private static final int STARTING_PROGRESS_ALPHA = (int) (.3f * MAX_ALPHA);
    private static final int CIRCLE_DIAMETER = 40;
    private static final float DECELERATE_INTERPOLATION_FACTOR = 2f;
    private static final int INVALID_POINTER = -1;
    private static final float DRAG_RATE = .5f;
    // Max amount of circle that can be filled by progress during swipe gesture,
    // where 1.0 is a full circle
    //    private static final float MAX_PROGRESS_ANGLE = .8f;
    private static final int SCALE_DOWN_DURATION = 150;
    private static final int ALPHA_ANIMATION_DURATION = 300;
    private static final int ANIMATE_TO_TRIGGER_DURATION = 200;
    private static final int ANIMATE_TO_START_DURATION = 200;
    // Default background for the progress spinner
    private static final int CIRCLE_BG_LIGHT = 0xFFFAFAFA;
    // Default offset in dips from the top of the view to where the progress spinner should stop
    private static final int DEFAULT_CIRCLE_TARGET = 64;
    //todo : dis v.
    //    private static final int[] LAYOUT_ATTRS = new int[]{
    //            android.R.attr.enabled
    //    };
    private final NestedScrollingParentHelper mNestedScrollingParentHelper;
    private final NestedScrollingChildHelper mNestedScrollingChildHelper;

    private final int[] mParentScrollConsumed = new int[2];
    private final int[] mParentOffsetInWindow = new int[2];

    private final DecelerateInterpolator mDecelerateInterpolator;

    protected int mFrom;
    protected int mOriginalOffsetTop;

    private int iconPaddingRight = 0;
    private int iconPaddingLeft = 0;
    private int iconPaddingTop = 0;
    private int iconPaddingBottom = 0;

    private Drawable icon;

    private View mTarget; // the target of the gesture
    private OnPullListener mListener;
    private boolean mRefreshing = false;
    private int mTouchSlop;
    private float mTotalDragDistance = -1;
    // If nested scrolling is enabled, the total amount that needed to be
    // consumed by this as the nested scrolling parent is used in place of the
    // overscroll determined by MOVE events in the onTouch handler
    private float mTotalUnconsumed;
    private boolean mNestedScrollInProgress;
    private int mMediumAnimationDuration;
    private int mCurrentTargetOffsetTop;
    // Whether or not the starting offset has been determined.
    private boolean mOriginalOffsetCalculated = false;
    private float mInitialMotionY;
    private float mInitialDownY;
    private boolean mIsBeingDragged;
    private int mActivePointerId = INVALID_POINTER;
    // Whether this item is scaled up rather than clipped
    private boolean mScale;
    // Target is returning to its start offset because it was cancelled or a
    // refresh was triggered.
    private boolean mReturningToStart;
    private CircleImageView mCircleView;
    private final Animation mAnimateToStartPosition = new Animation() {
        @Override
        public void applyTransformation(float interpolatedTime, Transformation t) {
            moveToStart(interpolatedTime);
        }
    };
    private int mCircleViewIndex = -1;
    private float mStartingScale;
    private Animation mScaleAnimation;
    private Animation mScaleDownAnimation;
    private Animation mAlphaStartAnimation;
    private Animation mAlphaMaxAnimation;
    private Animation mScaleDownToStartAnimation;
    private float mSpinnerFinalOffset;
    private boolean mNotify;
    private int mCircleWidth;
    private int mCircleHeight;
    // Whether the client has set a custom starting position;
    private boolean mUsingCustomStart;
    private final Animation mAnimateToCorrectPosition = new Animation() {
        @Override
        public void applyTransformation(float interpolatedTime, Transformation t) {
            int targetTop = 0;
            int endTarget = 0;
            if (!mUsingCustomStart) {
                endTarget = (int) (mSpinnerFinalOffset - Math.abs(mOriginalOffsetTop));
            } else {
                endTarget = (int) mSpinnerFinalOffset;
            }
            targetTop = (mFrom + (int) ((endTarget - mFrom) * interpolatedTime));
            int offset = targetTop - mCircleView.getTop();
            setTargetOffsetTopAndBottom(offset);
            //            mProgress.setArrowScale(1 - interpolatedTime);
        }
    };
    private Animation.AnimationListener mRefreshListener = new Animation.AnimationListener() {
        @Override
        public void onAnimationStart(Animation animation) {
        }

        @Override
        public void onAnimationRepeat(Animation animation) {
        }

        @Override
        public void onAnimationEnd(Animation animation) {
            if (mRefreshing) {
                // Make sure the progress view is fully visible
                //                icon.setAlpha(MAX_ALPHA);
                //                mProgress.setAlpha(MAX_ALPHA);
                //                mProgress.start();
                if (mNotify) {
                    if (mListener != null) {
                        mListener.onPull();
                    }
                }
                mCurrentTargetOffsetTop = mCircleView.getTop();
            } else {
                reset();
            }
        }
    };

    /**
     * Simple constructor to use when creating a SwipeRefreshLayout from code.
     *
     * @param context
     */
    public SwipeAction(Context context) {
        this(context, null);
    }

    /**
     * Constructor that is called when inflating SwipeRefreshLayout from XML.
     *
     * @param context
     * @param attrs
     */
    public SwipeAction(Context context, AttributeSet 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);
        initStyle(context, attrs);
        //        final TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.SwipeAction);
        ////        setEnabled(a.getBoolean(0, true));
        //        icon = a.getDrawable(R.styleable.SwipeAction_src);
        ////        if(icon == null) {
        ////            icon = getResources().getDrawable(android.R.drawable.ic_delete);
        ////        }
        //        a.recycle();
        final DisplayMetrics metrics = getResources().getDisplayMetrics();
        //todo : changeable size v.
        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;
        mNestedScrollingParentHelper = new NestedScrollingParentHelper(this);
        mNestedScrollingChildHelper = new NestedScrollingChildHelper(this);
        setNestedScrollingEnabled(true);
    }

    private void reset() {
        mCircleView.clearAnimation();
        //        mProgress.stop();
        mCircleView.setVisibility(View.GONE);
        setColorViewAlpha(MAX_ALPHA);
        // Return the circle to its start position
        if (mScale) {
            setAnimationProgress(0 /* animation complete and view is hidden */);
        } else {
            setTargetOffsetTopAndBottom(mOriginalOffsetTop - mCurrentTargetOffsetTop);
        }
        mCurrentTargetOffsetTop = mCircleView.getTop();
    }

    /**
     * One of DEFAULT, or LARGE.
     */
    //    public void setSize(int size) {
    //        if (size != MaterialSearchDrawable.LARGE && size != MaterialSearchDrawable.DEFAULT) {
    //            return;
    //        }
    //        final DisplayMetrics metrics = getResources().getDisplayMetrics();
    //        if (size == MaterialSearchDrawable.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);
    //    }
    @Override
    protected void onDetachedFromWindow() {
        super.onDetachedFromWindow();
        reset();
    }

    private void setColorViewAlpha(int targetAlpha) {
        mCircleView.getBackground().setAlpha(targetAlpha);
        //        mProgress.setAlpha(targetAlpha);
        //        icon.setAlpha(targetAlpha);
    }

    /**
     * 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.
     */
    public void setProgressViewOffset(boolean scale, int start, int end) {
        mScale = scale;
        mCircleView.setVisibility(View.GONE);
        mOriginalOffsetTop = mCurrentTargetOffsetTop = start;
        mSpinnerFinalOffset = end;
        mUsingCustomStart = true;
        mCircleView.invalidate();
    }

    /**
     * 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.
     */
    public void setProgressViewEndTarget(boolean scale, int end) {
        mSpinnerFinalOffset = end;
        mScale = scale;
        mCircleView.invalidate();
    }

    protected int getChildDrawingOrder(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 void createProgressView() {
        mCircleView = new CircleImageView(getContext(), CIRCLE_BG_LIGHT);
        mCircleView.setImageDrawable(icon);
        mCircleView.setPadding(iconPaddingLeft, iconPaddingTop, iconPaddingRight, iconPaddingBottom);
        mCircleView.setVisibility(View.GONE);
        addView(mCircleView);
    }

    /**
     * Set the icon inside {@link #mCircleView}
     *
     * @param icon Drawable to set as icon
     */
    public void setIcon(Drawable icon) {
        mCircleView.setImageDrawable(icon);
    }

    public void setBackgroundShape(Shape shape) {
        mCircleView.setBackgroundShape(shape);
    }

    public void setBackgroundColor(@ColorRes int colorRes) {
        mCircleView.setBackgroundColor(colorRes);
    }

    // todo : add custom view
    //    public void setCustomView(View customView) {
    //
    //    }

    public void setPadding(int iconPaddingLeft, int iconPaddingTop, int iconPaddingRight, int iconPaddingBottom) {
        mCircleView.setPadding(iconPaddingLeft, iconPaddingTop, iconPaddingRight, iconPaddingBottom);
    }

    public boolean isActing() {
        return mRefreshing;
    }

    /**
     * Set the listener to be notified when a refresh is triggered via the swipe
     * gesture.
     */
    public void addOnPullListener(OnPullListener listener) {
        mListener = listener;
    }

    /**
     * Notify the widget that refresh state has changed. Do not call this when
     * refresh is triggered by a swipe gesture.
     *
     * @param show Whether or not the view should show refresh progress.
     */
    public void setWorking(boolean show) {
        if (show && mRefreshing != show) {
            // scale and show
            mRefreshing = show;
            int endTarget;
            if (!mUsingCustomStart) {
                endTarget = (int) (mSpinnerFinalOffset + mOriginalOffsetTop);
            } else {
                endTarget = (int) mSpinnerFinalOffset;
            }
            setTargetOffsetTopAndBottom(endTarget - mCurrentTargetOffsetTop);
            mNotify = false;
            startScaleUpAnimation(mRefreshListener);
        } else {
            setWorking(show, false /* notify */);
        }
    }

    private void startScaleUpAnimation(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);
            //            icon.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);
    }

    private void setAnimationProgress(float progress) {
        ViewCompat.setScaleX(mCircleView, progress);
        ViewCompat.setScaleY(mCircleView, progress);

    }

    private void setWorking(boolean refreshing, final boolean notify) {
        if (mRefreshing != refreshing) {
            mNotify = notify;
            ensureTarget();
            mRefreshing = refreshing;
            if (mRefreshing) {
                animateOffsetToCorrectPosition(mCurrentTargetOffsetTop, mRefreshListener);
            } else {
                startScaleDownAnimation(mRefreshListener);
            }
        }
    }

    private void startScaleDownAnimation(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 void startProgressAlphaStartAnimation() {
        mAlphaStartAnimation = startAlphaAnimation(icon.getAlpha(), STARTING_PROGRESS_ALPHA);
    }

    private void startProgressAlphaMaxAnimation() {
        mAlphaMaxAnimation = startAlphaAnimation(icon.getAlpha(), MAX_ALPHA);
    }

    private Animation startAlphaAnimation(final int startingAlpha, final int endingAlpha) {
        // Pre API 11, alpha is used in place of scale. Don't also use it to
        // show the trigger point.
        if (mScale) {
            return null;
        }
        Animation alpha = new Animation() {
            @Override
            public void applyTransformation(float interpolatedTime, Transformation t) {
                //                icon
                //                        .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;
    }

    /**
     * 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 iconColor       Color of the icon
     * @param backgroundColor Color of the background disc
     */
    @ColorInt
    public void setColors(int iconColor, int backgroundColor) {
        ensureTarget();
        //todo : set color of icon and background
        //        mProgress.setColorSchemeColors(colors);

    }

    private void ensureTarget() {
        // 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;
                }
            }
        }
    }

    /**
     * Set the distance to trigger a sync in dips
     *
     * @param distance Distance in dips to trigger sync
     */
    public void setDistanceToTriggerSync(int distance) {
        mTotalDragDistance = distance;
    }

    @Override
    protected void onLayout(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);
    }

    @Override
    public void onMeasure(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;
            }
        }
    }

    /**
     * @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.
     */
    public boolean canChildScrollUp() {
        return ViewCompat.canScrollVertically(mTarget, -1);
    }

    @Override
    public boolean onInterceptTouchEvent(MotionEvent ev) {
        ensureTarget();
        final int action = MotionEventCompat.getActionMasked(ev);
        if (mReturningToStart && action == MotionEvent.ACTION_DOWN) {
            mReturningToStart = false;
        }
        if (!isEnabled() || mReturningToStart || canChildScrollUp() || mRefreshing || mNestedScrollInProgress) {
            // 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());
            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(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);
                //                    icon.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;
    }

    private float getMotionEventY(MotionEvent ev, int activePointerId) {
        final int index = MotionEventCompat.findPointerIndex(ev, activePointerId);
        if (index < 0) {
            return -1;
        }
        return MotionEventCompat.getY(ev, index);
    }

    @Override
    public void requestDisallowInterceptTouchEvent(boolean b) {
        // if this is a List < L or another view that doesn't support nested
        // scrolling, ignore this request so that the vertical scroll event
        // isn't stolen
        if (!((mTarget instanceof AbsListView)
                || (mTarget != null && !ViewCompat.isNestedScrollingEnabled(mTarget)))) {
            super.requestDisallowInterceptTouchEvent(b);
        }
    }

    // NestedScrollingParent
    @Override
    public boolean onStartNestedScroll(View child, View target, int nestedScrollAxes) {
        return isEnabled() && canChildScrollUp() && !mReturningToStart && !mRefreshing
                && (nestedScrollAxes & ViewCompat.SCROLL_AXIS_VERTICAL) != 0;
    }

    @Override
    public void onNestedScrollAccepted(View child, View target, int axes) {
        // Reset the counter of how much leftover scroll needs to be consumed.
        mNestedScrollingParentHelper.onNestedScrollAccepted(child, target, axes);
        // Dispatch up to the nested parent
        startNestedScroll(axes & ViewCompat.SCROLL_AXIS_VERTICAL);
        mTotalUnconsumed = 0;
        mNestedScrollInProgress = true;
    }

    @Override
    public void onNestedPreScroll(View target, int dx, int dy, int[] consumed) {
        // If we are in the middle of consuming, a scroll, then we want to move the spinner back up
        // before allowing the list to scroll
        if (dy > 0 && mTotalUnconsumed > 0) {
            if (dy > mTotalUnconsumed) {
                consumed[1] = dy - (int) mTotalUnconsumed;
                mTotalUnconsumed = 0;
            } else {
                mTotalUnconsumed -= dy;
                consumed[1] = dy;
            }
            moveSpinner(mTotalUnconsumed);
        }
        // If a client layout is using a custom start position for the circle
        // view, they mean to hide it again before scrolling the child view
        // If we get back to mTotalUnconsumed == 0 and there is more to go, hide
        // the circle so it isn't exposed if its blocking content is moved
        if (mUsingCustomStart && dy > 0 && mTotalUnconsumed == 0 && Math.abs(dy - consumed[1]) > 0) {
            mCircleView.setVisibility(View.GONE);
        }
        // Now let our nested parent consume the leftovers
        final int[] parentConsumed = mParentScrollConsumed;
        if (dispatchNestedPreScroll(dx - consumed[0], dy - consumed[1], parentConsumed, null)) {
            consumed[0] += parentConsumed[0];
            consumed[1] += parentConsumed[1];
        }
    }

    @Override
    public int getNestedScrollAxes() {
        return mNestedScrollingParentHelper.getNestedScrollAxes();
    }

    @Override
    public void onStopNestedScroll(View target) {
        mNestedScrollingParentHelper.onStopNestedScroll(target);
        mNestedScrollInProgress = false;
        // Finish the spinner for nested scrolling if we ever consumed any
        // unconsumed nested scroll
        if (mTotalUnconsumed > 0) {
            finishSpinner(mTotalUnconsumed);
            mTotalUnconsumed = 0;
        }
        // Dispatch up our nested parent
        stopNestedScroll();
    }

    @Override
    public void onNestedScroll(final View target, final int dxConsumed, final int dyConsumed,
            final int dxUnconsumed, final int dyUnconsumed) {
        // Dispatch up to the nested parent first
        dispatchNestedScroll(dxConsumed, dyConsumed, dxUnconsumed, dyUnconsumed, mParentOffsetInWindow);
        // This is a bit of a hack. Nested scrolling works from the bottom up, and as we are
        // sometimes between two nested scrolling views, we need a way to be able to know when any
        // nested scrolling parent has stopped handling events. We do that by using the
        // 'offset in window 'functionality to see if we have been moved from the event.
        // This is a decent indication of whether we should take over the event stream or not.
        final int dy = dyUnconsumed + mParentOffsetInWindow[1];
        if (dy < 0) {
            mTotalUnconsumed += Math.abs(dy);
            moveSpinner(mTotalUnconsumed);
        }
    }

    @Override
    public boolean isNestedScrollingEnabled() {
        return mNestedScrollingChildHelper.isNestedScrollingEnabled();
    }

    // NestedScrollingChild
    @Override
    public void setNestedScrollingEnabled(boolean enabled) {
        mNestedScrollingChildHelper.setNestedScrollingEnabled(enabled);
    }

    @Override
    public boolean startNestedScroll(int axes) {
        return mNestedScrollingChildHelper.startNestedScroll(axes);
    }

    @Override
    public void stopNestedScroll() {
        mNestedScrollingChildHelper.stopNestedScroll();
    }

    @Override
    public boolean hasNestedScrollingParent() {
        return mNestedScrollingChildHelper.hasNestedScrollingParent();
    }

    @Override
    public boolean dispatchNestedScroll(int dxConsumed, int dyConsumed, int dxUnconsumed, int dyUnconsumed,
            int[] offsetInWindow) {
        return mNestedScrollingChildHelper.dispatchNestedScroll(dxConsumed, dyConsumed, dxUnconsumed, dyUnconsumed,
                offsetInWindow);
    }

    @Override
    public boolean dispatchNestedPreScroll(int dx, int dy, int[] consumed, int[] offsetInWindow) {
        return mNestedScrollingChildHelper.dispatchNestedPreScroll(dx, dy, consumed, offsetInWindow);
    }

    @Override
    public boolean onNestedPreFling(View target, float velocityX, float velocityY) {
        return dispatchNestedPreFling(velocityX, velocityY);
    }

    @Override
    public boolean onNestedFling(View target, float velocityX, float velocityY, boolean consumed) {
        return dispatchNestedFling(velocityX, velocityY, consumed);
    }

    @Override
    public boolean dispatchNestedFling(float velocityX, float velocityY, boolean consumed) {
        return mNestedScrollingChildHelper.dispatchNestedFling(velocityX, velocityY, consumed);
    }

    @Override
    public boolean dispatchNestedPreFling(float velocityX, float velocityY) {
        return mNestedScrollingChildHelper.dispatchNestedPreFling(velocityX, velocityY);
    }

    private boolean isAnimationRunning(Animation animation) {
        return animation != null && animation.hasStarted() && !animation.hasEnded();
    }

    private void moveSpinner(float overscrollTop) {
        float originalDragPercent = overscrollTop / mTotalDragDistance;
        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 (icon.getAlpha() > STARTING_PROGRESS_ALPHA && !isAnimationRunning(mAlphaStartAnimation)) {
                // Animate the alpha
                startProgressAlphaStartAnimation();
            }
        } else {
            if (icon.getAlpha() < MAX_ALPHA && !isAnimationRunning(mAlphaMaxAnimation)) {
                // Animate the alpha
                startProgressAlphaMaxAnimation();
            }
        }
        float rotation = (-0.25f + .4f * adjustedPercent + tensionPercent * 2) * .5f;
        //        icon.setAlpha(255);
        mCircleView.animate().rotation(rotation);
        setTargetOffsetTopAndBottom(targetY - mCurrentTargetOffsetTop);
    }

    private void finishSpinner(float overscrollTop) {
        if (overscrollTop > mTotalDragDistance) {
            setWorking(true, true /* notify */);
        } else {
            // cancel refresh
            mRefreshing = false;
            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);
        }
    }

    @Override
    public boolean onTouchEvent(MotionEvent ev) {
        final int action = MotionEventCompat.getActionMasked(ev);
        int pointerIndex;
        if (mReturningToStart && action == MotionEvent.ACTION_DOWN) {
            mReturningToStart = false;
        }
        if (!isEnabled() || mReturningToStart || canChildScrollUp() || mNestedScrollInProgress) {
            // 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: {
            pointerIndex = MotionEventCompat.findPointerIndex(ev, mActivePointerId);
            if (pointerIndex < 0) {
                Log.e(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) {
                if (overscrollTop > 0) {
                    moveSpinner(overscrollTop);
                } else {
                    return false;
                }
            }
            break;
        }
        case MotionEventCompat.ACTION_POINTER_DOWN: {
            pointerIndex = MotionEventCompat.getActionIndex(ev);
            if (pointerIndex < 0) {
                Log.e(TAG, "Got ACTION_POINTER_DOWN event but have an invalid action index.");
                return false;
            }
            mActivePointerId = MotionEventCompat.getPointerId(ev, pointerIndex);
            break;
        }
        case MotionEventCompat.ACTION_POINTER_UP:
            onSecondaryPointerUp(ev);
            break;
        case MotionEvent.ACTION_UP: {
            pointerIndex = MotionEventCompat.findPointerIndex(ev, mActivePointerId);
            if (pointerIndex < 0) {
                Log.e(TAG, "Got ACTION_UP event but don't have an active pointer id.");
                return false;
            }
            final float y = MotionEventCompat.getY(ev, pointerIndex);
            final float overscrollTop = (y - mInitialMotionY) * DRAG_RATE;
            mIsBeingDragged = false;
            finishSpinner(overscrollTop);
            mActivePointerId = INVALID_POINTER;
            return false;
        }
        case MotionEvent.ACTION_CANCEL:
            return false;
        }
        return true;
    }

    private void animateOffsetToCorrectPosition(int from, 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 void animateOffsetToStartPosition(int from, 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);
        }
    }

    private void moveToStart(float interpolatedTime) {
        int targetTop;
        targetTop = (mFrom + (int) ((mOriginalOffsetTop - mFrom) * interpolatedTime));
        int offset = targetTop - mCircleView.getTop();
        setTargetOffsetTopAndBottom(offset);
    }

    private void startScaleDownReturnToStartAnimation(int from, Animation.AnimationListener listener) {
        mFrom = from;

        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 void setTargetOffsetTopAndBottom(int offset) {
        mCircleView.bringToFront();
        mCircleView.offsetTopAndBottom(offset);
        mCurrentTargetOffsetTop = mCircleView.getTop();
    }

    private void onSecondaryPointerUp(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);
        }
    }

    private void initStyle(Context context, AttributeSet attrs) {
        final TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.SwipeAction);
        if (a != null) {
            if (a.hasValue(R.styleable.SwipeAction_src)) {
                icon = a.getDrawable(R.styleable.SwipeAction_src);
            } else {
                //default back to available icon
                icon = getResources().getDrawable(android.R.drawable.ic_delete);
            }
            iconPaddingBottom = Math
                    .round(a.getDimension(R.styleable.SwipeAction_iconPaddingBottom, DEF_PADDING_BOTTOM));
            iconPaddingTop = Math.round(a.getDimension(R.styleable.SwipeAction_iconPaddingTop, DEF_PADDING_TOP));
            iconPaddingLeft = Math
                    .round(a.getDimension(R.styleable.SwipeAction_iconPaddingLeft, DEF_PADDING_START));
            iconPaddingRight = Math
                    .round(a.getDimension(R.styleable.SwipeAction_iconPaddingRight, DEF_PADDING_END));
            a.recycle();
        }
    }

    /**
     * Classes that wish to be notified when the swipe gesture correctly
     * triggers a refresh should implement this interface.
     */
    public interface OnPullListener {
        void onPull();
    }
}