com.ray.appchallenge.view.SwipeRefreshLayoutBottom.java Source code

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Here is the source code for com.ray.appchallenge.view.SwipeRefreshLayoutBottom.java

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package com.ray.appchallenge.view;

import android.content.Context;

import android.content.res.Resources;
import android.content.res.TypedArray;

import android.support.v4.view.MotionEventCompat;
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;

/*
 * Copyright (C) 2013 The Android Open Source Project
 *
 * 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.
 *
 * https://bitbucket.org/andreyice/swiperefreshlayoutbottom/src/6b50524995253a7ecac1d8a0b9489d37436176f4/src/android/support/library21/custom/?at=master
 */
public class SwipeRefreshLayoutBottom extends ViewGroup {

    // Maps to ProgressBar.Large style
    public static final int LARGE = MaterialProgressDrawable.LARGE;

    // Maps to ProgressBar default style
    public static final int DEFAULT = MaterialProgressDrawable.DEFAULT;

    private static final String LOG_TAG = SwipeRefreshLayoutBottom.class.getSimpleName();

    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 int CIRCLE_DIAMETER_LARGE = 56;

    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;

    private View mTarget; // the target of the gesture
    private OnRefreshListener mListener;
    private boolean mRefreshing = false;
    private int mTouchSlop;
    private float mTotalDragDistance = -1;
    private int mMediumAnimationDuration;
    private int mCurrentTargetOffsetTop;

    // Whether or not the starting offset has been determined.
    private boolean mOriginalOffsetCalculated = false;

    private float mInitialMotionY;
    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 final DecelerateInterpolator mDecelerateInterpolator;
    private static final int[] LAYOUT_ATTRS = new int[] { android.R.attr.enabled };

    private CircleImageView mCircleView;
    private int mCircleViewIndex = -1;

    protected int mFrom;

    private float mStartingScale;

    protected int mOriginalOffsetTop;

    private MaterialProgressDrawable mProgress;

    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 Animation.AnimationListener mRefreshListener = new Animation.AnimationListener() {
        @Override
        public void onAnimationStart(final Animation animation) {
        }

        @Override
        public void onAnimationRepeat(final Animation animation) {
        }

        @Override
        public void onAnimationEnd(final Animation animation) {
            if (mRefreshing) {

                // Make sure the progress view is fully visible
                mProgress.setAlpha(MAX_ALPHA);
                mProgress.start();
                if (mNotify) {
                    if (mListener != null) {
                        mListener.onRefresh();
                    }
                }
            } else {
                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,
                            true /* requires update */);
                }
            }

            mCurrentTargetOffsetTop = mCircleView.getTop();
        }
    };

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

    /**
     * One of DEFAULT, or LARGE.
     */
    public void setSize(final int size) {
        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);
    }

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

    /**
     * Constructor that is called when inflating SwipeRefreshLayout from XML.
     *
     * @param  context
     * @param  attrs
     */
    public SwipeRefreshLayoutBottom(final Context context, final 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);

        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;
    }

    protected int getChildDrawingOrder(final int childCount, final 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, CIRCLE_DIAMETER / 2);
        mProgress = new MaterialProgressDrawable(getContext(), this);
        mProgress.setBackgroundColor(CIRCLE_BG_LIGHT);
        mCircleView.setImageDrawable(mProgress);
        mCircleView.setVisibility(View.GONE);
        addView(mCircleView);
    }

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

    /**
     * Pre API 11, alpha is used to make the progress circle appear instead of scale.
     */
    private boolean isAlphaUsedForScale() {
        return android.os.Build.VERSION.SDK_INT < 11;
    }

    /**
     * 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.
     */
    public void setRefreshing(final boolean refreshing) {
        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 void startScaleUpAnimation(final 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(final float interpolatedTime, final Transformation t) {
                setAnimationProgress(interpolatedTime);
            }
        };
        mScaleAnimation.setDuration(mMediumAnimationDuration);
        if (listener != null) {
            mCircleView.setAnimationListener(listener);
        }

        mCircleView.clearAnimation();
        mCircleView.startAnimation(mScaleAnimation);
    }

    /**
     * Pre API 11, this does an alpha animation.
     *
     * @param  progress
     */
    private void setAnimationProgress(final float progress) {
        if (isAlphaUsedForScale()) {
            setColorViewAlpha((int) (progress * MAX_ALPHA));
        } else {
            ViewCompat.setScaleX(mCircleView, progress);
            ViewCompat.setScaleY(mCircleView, progress);
        }
    }

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

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

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

    private void startProgressAlphaMaxAnimation() {
        mAlphaMaxAnimation = startAlphaAnimation(mProgress.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 && isAlphaUsedForScale()) {
            return null;
        }

        Animation alpha = new Animation() {
            @Override
            public void applyTransformation(final float interpolatedTime, final 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;
    }

    /**
     * Set the background color of the progress spinner disc.
     *
     * @param  colorRes  Resource id of the color.
     */
    public void setProgressBackgroundColor(final int colorRes) {
        mCircleView.setBackgroundColor(colorRes);
        mProgress.setBackgroundColor(getResources().getColor(colorRes));
    }

    /**
     * @deprecated  Use {@link #setColorSchemeResources(int...)}
     */
    @Deprecated
    public void setColorScheme(final int... colors) {
        setColorSchemeResources(colors);
    }

    /**
     * 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
     */
    public void setColorSchemeResources(final int... 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);
    }

    /**
     * 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
     */
    public void setColorSchemeColors(final int... colors) {
        ensureTarget();
        mProgress.setColorSchemeColors(colors);
    }

    /**
     * @return  Whether the SwipeRefreshWidget is actively showing refresh progress.
     */
    public boolean isRefreshing() {
        return mRefreshing;
    }

    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
     */
    public void setDistanceToTriggerSync(final int distance) {
        mTotalDragDistance = distance;
    }

    @Override
    protected void onLayout(final boolean changed, final int left, final int top, final int right,
            final 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(final int widthMeasureSpec, final 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 = getMeasuredHeight() - mCircleView.getMeasuredHeight(); // TODO
        }

        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() {
     *  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);
     *  }
     *}*/

    public boolean canChildScrollUp() {

        Log.w("ANDREY", "canChildScrollUp()");

        if (android.os.Build.VERSION.SDK_INT < 14) {
            if (mTarget instanceof AbsListView) {
                final AbsListView absListView = (AbsListView) mTarget;

                Log.e("ANDREY", " absListView.getFirstVisiblePosition() " + absListView.getFirstVisiblePosition());
                Log.e("ANDREY", " absListView.getLastVisiblePosition() " + absListView.getLastVisiblePosition());
                Log.e("ANDREY", " absListView.getCount() " + absListView.getCount());

                if (absListView.getLastVisiblePosition() + 1 == absListView.getCount()) {

                    int lastIndex = absListView.getLastVisiblePosition() - absListView.getFirstVisiblePosition();

                    Log.e("ANDREY", " lastIndex  " + lastIndex);

                    boolean res = absListView.getChildAt(lastIndex).getBottom() == absListView.getPaddingBottom();

                    if (!res) {
                        Log.e("ANDREY", "return " + res);
                    }

                    return res;

                }

                // Log.e("ANDREY", "return TRUE");
                return true;

                /*
                 * return absListView.getChildCount() > 0
                 *      && (absListView.getFirstVisiblePosition() > 0 || absListView.getChildAt(0).getTop() <
                 * absListView.getPaddingTop());*/

            } else {
                Log.e("ANDREY", "return 222 " + (mTarget.getScrollY() > 0));
                return mTarget.getScrollY() > 0;
            }
        } else {

            Log.e("ANDREY", "return 333 " + (ViewCompat.canScrollVertically(mTarget, 1)));

            return ViewCompat.canScrollVertically(mTarget, 1);
        }

        // return  ViewCompat.canScrollVertically(mTarget, 1);

    }

    public boolean canChildScrollDown() { // TODO
        if (android.os.Build.VERSION.SDK_INT < 14) {
            if (mTarget instanceof AbsListView) {
                final AbsListView absListView = (AbsListView) mTarget;
                try {
                    if (absListView.getCount() > 0) {
                        if (absListView.getLastVisiblePosition() + 1 == absListView.getCount()) {
                            int lastIndex = absListView.getLastVisiblePosition()
                                    - absListView.getFirstVisiblePosition();
                            return absListView.getChildAt(lastIndex).getBottom() == absListView.getPaddingBottom();
                        }
                    }
                } catch (Exception e) {
                    e.printStackTrace();
                }

                return true;
            } else {
                return true;
            }
        } else {
            return ViewCompat.canScrollVertically(mTarget, 1);
        }
    }

    @Override
    public boolean onInterceptTouchEvent(final MotionEvent ev) {
        ensureTarget();

        final int action = MotionEventCompat.getActionMasked(ev);

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

        // if (!isEnabled() || mReturningToStart || canChildScrollUp() || mRefreshing) {
        if (!isEnabled() || mReturningToStart || canChildScrollDown() || mRefreshing) { // TODO

            // 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 initialMotionY = getMotionEventY(ev, mActivePointerId);
            if (initialMotionY == -1) {
                return false;
            }

            mInitialMotionY = initialMotionY;

        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 - mInitialMotionY;
            final float yDiff = mInitialMotionY - y; // TODO
            if (yDiff > mTouchSlop && !mIsBeingDragged) {
                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;
    }

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

        return MotionEventCompat.getY(ev, index);
    }

    @Override
    public void requestDisallowInterceptTouchEvent(final boolean b) {
        // Nope.
    }

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

    @Override
    public boolean onTouchEvent(final MotionEvent ev) {
        final int action = MotionEventCompat.getActionMasked(ev);

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

        // if (!isEnabled() || mReturningToStart || canChildScrollUp()) {
        if (!isEnabled() || mReturningToStart || canChildScrollDown()) { // TODO

            // 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;
            final float overscrollTop = (mInitialMotionY - y) * DRAG_RATE; // TODO
            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);
                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 = (float) (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;
            final float overscrollTop = (mInitialMotionY - y) * DRAG_RATE; // TODO
            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(final Animation animation) {
                        }

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

                        @Override
                        public void onAnimationRepeat(final Animation animation) {
                        }

                    };
                }

                animateOffsetToStartPosition(mCurrentTargetOffsetTop, listener);
                mProgress.showArrow(false);
            }

            mActivePointerId = INVALID_POINTER;
            return false;
        }
        }

        return true;
    }

    private void animateOffsetToCorrectPosition(final int from, final 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(final int from, final 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 final Animation mAnimateToCorrectPosition = new Animation() {
        @Override
        public void applyTransformation(final float interpolatedTime, final Transformation t) {
            int targetTop = 0;
            int endTarget = 0;
            if (!mUsingCustomStart) {
                endTarget = getMeasuredHeight() - (int) (mSpinnerFinalOffset); // TODO
            } else {
                endTarget = (int) mSpinnerFinalOffset;
            }

            targetTop = (mFrom + (int) ((endTarget - mFrom) * interpolatedTime));

            int offset = targetTop - mCircleView.getTop();
            setTargetOffsetTopAndBottom(offset, false /* requires update */);
        }
    };

    private void moveToStart(final float interpolatedTime) {
        int targetTop = 0;
        targetTop = (mFrom + (int) ((mOriginalOffsetTop - mFrom) * interpolatedTime));

        int offset = targetTop - mCircleView.getTop();
        setTargetOffsetTopAndBottom(offset, false /* requires update */);
    }

    private final Animation mAnimateToStartPosition = new Animation() {
        @Override
        public void applyTransformation(final float interpolatedTime, final Transformation t) {
            moveToStart(interpolatedTime);
        }
    };

    private void startScaleDownReturnToStartAnimation(final int from, final Animation.AnimationListener listener) {
        mFrom = from;
        if (isAlphaUsedForScale()) {
            mStartingScale = mProgress.getAlpha();
        } else {
            mStartingScale = ViewCompat.getScaleX(mCircleView);
        }

        mScaleDownToStartAnimation = new Animation() {
            @Override
            public void applyTransformation(final float interpolatedTime, final 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(final int offset, final boolean requiresUpdate) {
        mCircleView.bringToFront();
        mCircleView.offsetTopAndBottom(offset);
        mCurrentTargetOffsetTop = mCircleView.getTop();
        if (requiresUpdate && android.os.Build.VERSION.SDK_INT < 11) {
            invalidate();
        }
    }

    private void onSecondaryPointerUp(final 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);
        }
    }

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