Android 仿微信对话列表滑动删除效果

package com.fxsky.swipelist.widget;import android.annotation.SuppressLint;import android.content.Context;import android.content.res.TypedArray;import android.os.Handler;import android.os.Message;import android.util.AttributeSet;import android.view.MotionEvent;import android.view.View;import android.widget.ListView;import com.fxsky.swipelist.R;public class SwipeListView extends ListView {    private Boolean mIsHorizontal;    private View mPreItemView;    private View mCurrentItemView;    private float mFirstX;    private float mFirstY;    private int mRightViewWidth;    // private boolean mIsInAnimation = false;    private final int mDuration = 100;    private final int mDurationStep = 10;    private boolean mIsShown;    public SwipeListView(Context context) {        this(context,null);    }    public SwipeListView(Context context, AttributeSet attrs) {        this(context, attrs,0);    }    public SwipeListView(Context context, AttributeSet attrs, int defStyle) {        super(context, attrs, defStyle);                TypedArray mTypedArray = context.obtainStyledAttributes(attrs,                  R.styleable.swipelistviewstyle);                //获取自定义属性和默认值        mRightViewWidth = (int) mTypedArray.getDimension(R.styleable.swipelistviewstyle_right_width, 200);               mTypedArray.recycle();      }    /**     * return true, deliver to listView. return false, deliver to child. if     * move, return true     */    @Override    public boolean onInterceptTouchEvent(MotionEvent ev) {        float lastX = ev.getX();        float lastY = ev.getY();        switch (ev.getAction()) {            case MotionEvent.ACTION_DOWN:                mIsHorizontal = null;                System.out.println("onInterceptTouchEvent----->ACTION_DOWN");                mFirstX = lastX;                mFirstY = lastY;                int motionPosition = pointToPosition((int)mFirstX, (int)mFirstY);                if (motionPosition >= 0) {                    View currentItemView = getChildAt(motionPosition - getFirstVisiblePosition());                    mPreItemView = mCurrentItemView;                    mCurrentItemView = currentItemView;                }                break;            case MotionEvent.ACTION_MOVE:                float dx = lastX - mFirstX;                float dy = lastY - mFirstY;                if (Math.abs(dx) >= 5 && Math.abs(dy) >= 5) {                    return true;                }                break;            case MotionEvent.ACTION_UP:            case MotionEvent.ACTION_CANCEL:                System.out.println("onInterceptTouchEvent----->ACTION_UP");                if (mIsShown && (mPreItemView != mCurrentItemView || isHitCurItemLeft(lastX))) {                    System.out.println("1---> hiddenRight");                    /**                     * 情况一：                     * <p>                     * 一个Item的右边布局已经显示，                     * <p>                     * 这时候点击任意一个item, 那么那个右边布局显示的item隐藏其右边布局                     */                    hiddenRight(mPreItemView);                }                break;        }        return super.onInterceptTouchEvent(ev);    }    private boolean isHitCurItemLeft(float x) {        return x < getWidth() - mRightViewWidth;    }    /**     * @param dx     * @param dy     * @return judge if can judge scroll direction     */    private boolean judgeScrollDirection(float dx, float dy) {        boolean canJudge = true;        if (Math.abs(dx) > 30 && Math.abs(dx) > 2 * Math.abs(dy)) {            mIsHorizontal = true;            System.out.println("mIsHorizontal---->" + mIsHorizontal);        } else if (Math.abs(dy) > 30 && Math.abs(dy) > 2 * Math.abs(dx)) {            mIsHorizontal = false;            System.out.println("mIsHorizontal---->" + mIsHorizontal);        } else {            canJudge = false;        }        return canJudge;    }    /**     * return false, can't move any direction. return true, cant't move     * vertical, can move horizontal. return super.onTouchEvent(ev), can move     * both.     */    @Override    public boolean onTouchEvent(MotionEvent ev) {        float lastX = ev.getX();        float lastY = ev.getY();        switch (ev.getAction()) {            case MotionEvent.ACTION_DOWN:                System.out.println("---->ACTION_DOWN");                break;            case MotionEvent.ACTION_MOVE:                float dx = lastX - mFirstX;                float dy = lastY - mFirstY;                // confirm is scroll direction                if (mIsHorizontal == null) {                    if (!judgeScrollDirection(dx, dy)) {                        break;                    }                }                if (mIsHorizontal) {                    if (mIsShown && mPreItemView != mCurrentItemView) {                        System.out.println("2---> hiddenRight");                        /**                         * 情况二：                         * <p>                         * 一个Item的右边布局已经显示，                         * <p>                         * 这时候左右滑动另外一个item,那个右边布局显示的item隐藏其右边布局                         * <p>                         * 向左滑动只触发该情况，向右滑动还会触发情况五                         */                        hiddenRight(mPreItemView);                    }                    if (mIsShown && mPreItemView == mCurrentItemView) {                        dx = dx - mRightViewWidth;                        System.out.println("======dx " + dx);                    }                    // can't move beyond boundary                    if (dx < 0 && dx > -mRightViewWidth) {                        mCurrentItemView.scrollTo((int)(-dx), 0);                    }                    return true;                } else {                    if (mIsShown) {                        System.out.println("3---> hiddenRight");                        /**                         * 情况三：                         * <p>                         * 一个Item的右边布局已经显示，                         * <p>                         * 这时候上下滚动ListView,那么那个右边布局显示的item隐藏其右边布局                         */                        hiddenRight(mPreItemView);                    }                }                break;            case MotionEvent.ACTION_UP:            case MotionEvent.ACTION_CANCEL:                System.out.println("============ACTION_UP");                clearPressedState();                if (mIsShown) {                    System.out.println("4---> hiddenRight");                    /**                     * 情况四：                     * <p>                     * 一个Item的右边布局已经显示，                     * <p>                     * 这时候左右滑动当前一个item,那个右边布局显示的item隐藏其右边布局                     */                    hiddenRight(mPreItemView);                }                if (mIsHorizontal != null && mIsHorizontal) {                    if (mFirstX - lastX > mRightViewWidth / 2) {                        showRight(mCurrentItemView);                    } else {                        System.out.println("5---> hiddenRight");                        /**                         * 情况五：                         * <p>                         * 向右滑动一个item,且滑动的距离超过了右边View的宽度的一半，隐藏之。                         */                        hiddenRight(mCurrentItemView);                    }                    return true;                }                break;        }        return super.onTouchEvent(ev);    }    private void clearPressedState() {        // TODO current item is still has background, issue        mCurrentItemView.setPressed(false);        setPressed(false);        refreshDrawableState();        // invalidate();    }    private void showRight(View view) {        System.out.println("=========showRight");        Message msg = new MoveHandler().obtainMessage();        msg.obj = view;        msg.arg1 = view.getScrollX();        msg.arg2 = mRightViewWidth;        msg.sendToTarget();        mIsShown = true;    }    private void hiddenRight(View view) {        System.out.println("=========hiddenRight");        if (mCurrentItemView == null) {            return;        }        Message msg = new MoveHandler().obtainMessage();//        msg.obj = view;        msg.arg1 = view.getScrollX();        msg.arg2 = 0;        msg.sendToTarget();        mIsShown = false;    }    /**     * show or hide right layout animation     */    @SuppressLint("HandlerLeak")    class MoveHandler extends Handler {        int stepX = 0;        int fromX;        int toX;        View view;        private boolean mIsInAnimation = false;        private void animatioOver() {            mIsInAnimation = false;            stepX = 0;        }        @Override        public void handleMessage(Message msg) {            super.handleMessage(msg);            if (stepX == 0) {                if (mIsInAnimation) {                    return;                }                mIsInAnimation = true;                view = (View)msg.obj;                fromX = msg.arg1;                toX = msg.arg2;                stepX = (int)((toX - fromX) * mDurationStep * 1.0 / mDuration);                if (stepX < 0 && stepX > -1) {                    stepX = -1;                } else if (stepX > 0 && stepX < 1) {                    stepX = 1;                }                if (Math.abs(toX - fromX) < 10) {                    view.scrollTo(toX, 0);                    animatioOver();                    return;                }            }            fromX += stepX;            boolean isLastStep = (stepX > 0 && fromX > toX) || (stepX < 0 && fromX < toX);            if (isLastStep) {                fromX = toX;            }            view.scrollTo(fromX, 0);            invalidate();            if (!isLastStep) {                this.sendEmptyMessageDelayed(0, mDurationStep);            } else {                animatioOver();            }        }    }    public int getRightViewWidth() {        return mRightViewWidth;    }    public void setRightViewWidth(int mRightViewWidth) {        this.mRightViewWidth = mRightViewWidth;    }}