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Android实现侧滑recycleView+CardVeiw卡片阴影效果
Android实现侧滑recycleView+CardVeiw卡片阴影效果
关于
本篇主要实现侧滑菜单栏+卡片布局+无间距效果
效果图
普通的侧滑删除（这不是本篇重点）
主题卡片阴影的侧滑删除（间隙效果）
主题卡片阴影的侧滑删除无间距效果
第一步，定义基本SlideRecyclerView
定义侧滑删除的recycleView，网上一搜一大堆，这里就不做讲解了。基本上就是通过
VelocityTracker判断是否有x坐标的移动，有则进行拦截处理事件。class SlideRecyclerView : RecyclerView { /**滑动的itemView */ private var mMoveView: ViewGroup? = null /**itemView中菜单控件宽度 */ private var mMenuWidth = 0 private var mVelocity: VelocityTracker? = null /**触碰时的首个横坐标 */ private var mFirstX = 0 /**触碰时的首个纵坐标 */ private var mFirstY = 0 /**触碰末次的横坐标 */ private var mLastX = 0 /**最小滑动距离 */ private var mTouchSlop = 0 private var mScroller: Scroller? = null /**是否正在水平滑动 */ private var mMoving = false /**是否由onInterceptTouchEvent（）方法拦截 */ private var mIntercepted = false constructor(context: Context?) : super(context!!) { init() } constructor(context: Context?, attrs: AttributeSet?) : super( context!!, attrs ) { init() } constructor(context: Context?, attrs: AttributeSet?, defStyle: Int) : super( context!!, attrs, defStyle ) { init() } private fun init() { mTouchSlop = ViewConfiguration.get(context).scaledTouchSlop mScroller = Scroller(context) } override fun onInterceptTouchEvent(e: MotionEvent): Boolean { val x = e.x.toInt() val y = e.y.toInt() addVelocityEvent(e) when (e.action) { MotionEvent.ACTION_DOWN -> { //若Scroller处于动画中，则终止动画 if (!mScroller!!.isFinished) { mScroller!!.abortAnimation() } mFirstX = x mFirstY = y mLastX = x //获取点击区域所在的itemView val view = findChildViewUnder(x.toFloat(), y.toFloat()) as ViewGroup? //在点击区域以外的itemView开着菜单，则关闭菜单并拦截该次触碰事件 if (mMoveView != null && view !== mMoveView && mMoveView!!.scrollX != 0) { closeMenu() mIntercepted = true return true } mMoveView = view //获取itemView中菜单的宽度（规定itemView中为两个子View） mMenuWidth = if (mMoveView != null && mMoveView!!.childCount == 2) { mMoveView!!.getChildAt(1).width } else { -1 } } MotionEvent.ACTION_MOVE -> { mVelocity!!.computeCurrentVelocity(1000) val velocityX = Math.abs(mVelocity!!.xVelocity).toInt() val velocityY = Math.abs(mVelocity!!.yVelocity).toInt() val moveX = Math.abs(x - mFirstX) val moveY = Math.abs(y - mFirstY) //满足如下条件其一则判定为水平滑动： //1、水平速度大于竖直速度,且水平速度大于最小速度 //2、水平位移大于竖直位移,且大于最小移动距离 //必需条件：itemView菜单栏宽度大于0，且recyclerView处于静止状态（即并不在竖直滑动） val isHorizontalMove = (Math.abs(velocityX) >= MINIMUM_VELOCITY && velocityX > velocityY || moveX > moveY && moveX > mTouchSlop) && mMenuWidth > 0 && scrollState == 0 if (isHorizontalMove) { mIntercepted = true return true } } MotionEvent.ACTION_UP, MotionEvent.ACTION_CANCEL -> { releaseVelocity() //itemView以及其子view触发点击事件，菜单未关闭则直接关闭 closeMenuNow() } else -> { } } return super.onInterceptTouchEvent(e) } override fun onTouchEvent(e: MotionEvent): Boolean { val x = e.x.toInt() val y = e.y.toInt() addVelocityEvent(e) when (e.action) { MotionEvent.ACTION_DOWN -> //若是通过onInterceptTouchEvent（）方法ACTION_DOWN拦截而来的，则丢弃此次事件 if (mIntercepted) { mIntercepted = false return false } MotionEvent.ACTION_MOVE -> { mVelocity!!.computeCurrentVelocity(1000) val velocityX = Math.abs(mVelocity!!.xVelocity).toInt() val velocityY = Math.abs(mVelocity!!.yVelocity).toInt() val moveX = Math.abs(x - mFirstX) val moveY = Math.abs(y - mFirstY) val isHorizontalMove = mIntercepted || mMoving || (Math.abs(velocityX) >= MINIMUM_VELOCITY && velocityX > velocityY || moveX > moveY && moveX > mTouchSlop) && mMenuWidth > 0 && scrollState == 0 if (isHorizontalMove) { val dx = mLastX - x //让itemView在规定区域随手指移动 if (mMoveView!!.scrollX + dx in 0..mMenuWidth) { mMoveView!!.scrollBy(dx, 0) } mLastX = x //设置正处于水平滑动状态 mMoving = true mIntercepted = false return true } } MotionEvent.ACTION_UP, MotionEvent.ACTION_CANCEL -> { if (mMoving) { mMoving = false mVelocity!!.computeCurrentVelocity(1000) val scrollX = mMoveView!!.scrollX //若速度大于正方向最小速度，则关闭菜单栏；若速度小于反方向最小速度，则打开菜单栏 //若速度没到判断条件，则对菜单显示的宽度进行判断打开/关闭菜单 if (mVelocity!!.xVelocity >= MINIMUM_VELOCITY) { mScroller!!.startScroll(scrollX, 0, -scrollX, 0, Math.abs(scrollX)) } else if (mVelocity!!.xVelocity < -MINIMUM_VELOCITY) { val dx = mMenuWidth - scrollX mScroller!!.startScroll(scrollX, 0, dx, 0, Math.abs(dx)) } else if (scrollX > mMenuWidth / 2) { val dx = mMenuWidth - scrollX mScroller!!.startScroll(scrollX, 0, dx, 0, Math.abs(dx)) } else { mScroller!!.startScroll(scrollX, 0, -scrollX, 0, Math.abs(scrollX)) } invalidate() } else if (mMoveView != null && mMoveView!!.scrollX != 0) { //若不是水平滑动状态，菜单栏开着则关闭 closeMenu() } releaseVelocity() } else -> { } } return super.onTouchEvent(e) } override fun computeScroll() { if (mScroller!!.computeScrollOffset()) { if (isInWindow(mMoveView)) { mMoveView!!.scrollTo(mScroller!!.currX, 0) invalidate() } else { //若处于动画的itemView滑出屏幕，则终止动画，并让其到达结束点位置 mScroller!!.abortAnimation() mMoveView!!.scrollTo(mScroller!!.finalX, 0) } } } /** * 使用Scroller关闭菜单栏 */ fun closeMenu() { mScroller!!.startScroll(mMoveView!!.scrollX, 0, -mMoveView!!.scrollX, 0, 300) invalidate() } /** * 即刻关闭菜单栏 */ fun closeMenuNow() { if (mMoveView != null && mMoveView!!.scrollX != 0) { mMoveView!!.scrollTo(0, 0) } } /** * 获取VelocityTracker实例，并为其添加事件 * @param e 触碰事件 */ private fun addVelocityEvent(e: MotionEvent) { if (mVelocity == null) { mVelocity = VelocityTracker.obtain() } mVelocity!!.addMovement(e) } /** * 释放VelocityTracker */ private fun releaseVelocity() { if (mVelocity != null) { mVelocity!!.clear() mVelocity!!.recycle() mVelocity = null } } /** * 判断该itemView是否显示在屏幕内 * @param view itemView * @return isInWindow */ private fun isInWindow(view: View?): Boolean { if (layoutManager is LinearLayoutManager) { val manager = layoutManager as LinearLayoutManager? val firstPosition = manager!!.findFirstVisibleItemPosition() val lastPosition = manager.findLastVisibleItemPosition() val currentPosition = manager.getPosition(view!!) return currentPosition in firstPosition..lastPosition } return true } companion object { /**最小速度 */ private const val MINIMUM_VELOCITY = 500 } }- 1
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基本使用
在布局代码中添加引用，其他的使用和recycleView定义一样：
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:app="http://schemas.android.com/apk/res-auto" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" android:background="#FFFFFF" tools:context=".RecycleViewShowActivity"> <View android:id="@+id/home_title_bg" android:layout_width="match_parent" android:layout_height="75dp" app:layout_constraintTop_toTopOf="parent" /> <TextView android:id="@+id/tv_title" android:layout_width="wrap_content" android:layout_height="wrap_content" app:layout_constraintTop_toTopOf="parent" android:layout_marginTop="@dimen/dp_25" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" android:textAllCaps="true" android:textColor="#333333" android:textSize="18sp" android:textStyle="bold" /> <com.tobeyr1.app.SlideRecyclerView android:id="@+id/rv_show" android:layout_width="match_parent" android:layout_height="wrap_content" app:layout_constraintTop_toBottomOf="@id/tv_title" /> androidx.constraintlayout.widget.ConstraintLayout>- 1
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添加布局item_inbox_card_list_vertical:
<androidx.appcompat.widget.LinearLayoutCompat xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="116dp" android:orientation="horizontal" android:layout_marginTop="16dp" xmlns:app="http://schemas.android.com/apk/res-auto"> <androidx.constraintlayout.widget.ConstraintLayout android:id="@+id/layout_content" android:layout_width="match_parent" android:background="#BDDDFF" android:layout_height="match_parent"> <TextView android:id="@+id/tv_inbox_name" android:layout_width="wrap_content" android:layout_height="wrap_content" android:textSize="18sp" android:textColor="#333333" android:text="RecycleView+CardView" android:maxLines="1" android:ellipsize="end" app:layout_constraintTop_toTopOf="@id/layout_content" app:layout_constraintBottom_toBottomOf="@id/layout_content" app:layout_constraintStart_toStartOf="@id/layout_content" app:layout_constraintEnd_toEndOf="@id/layout_content" /> androidx.constraintlayout.widget.ConstraintLayout> <LinearLayout android:layout_width="@dimen/dp_74" android:layout_height="match_parent" android:layout_gravity="center_vertical" android:orientation="horizontal"> <TextView android:id="@+id/tv_Delete" android:layout_width="@dimen/dp_74" android:layout_height="match_parent" android:background="#ccf44336" android:text="Delete" android:gravity="center_horizontal" android:textSize="10sp" android:paddingTop="@dimen/dp_20" android:layout_gravity="center" android:textColor="#FFFFFF" app:drawableTopCompat="@drawable/ic_game_list_delete" /> LinearLayout> androidx.appcompat.widget.LinearLayoutCompat>- 1
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cardView使用
修改页面布局，cardView不能设置宽高match_parent，否则没有阴影效果，设置好cardView的margin边距之后，它的父布局宽高一定大于cardview本身大小，以便阴影可以被绘制出来。
<androidx.appcompat.widget.LinearLayoutCompat xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="116dp" android:orientation="horizontal" android:layout_marginTop="16dp" xmlns:app="http://schemas.android.com/apk/res-auto"> <androidx.constraintlayout.widget.ConstraintLayout android:layout_width="match_parent" android:layout_height="@dimen/dp_116"> <androidx.cardview.widget.CardView android:layout_width="match_parent" android:layout_height="@dimen/dp_104" app:cardElevation="@dimen/dp_3" android:layout_marginStart="@dimen/dp_16" android:layout_marginEnd="@dimen/dp_16" android:layout_marginTop="@dimen/dp_6" android:layout_marginBottom="@dimen/dp_6" app:layout_constraintBottom_toBottomOf="parent" app:cardBackgroundColor="#BDDDFF"> <androidx.constraintlayout.widget.ConstraintLayout android:id="@+id/layout_content" android:layout_width="match_parent" android:layout_height="match_parent"> <TextView android:id="@+id/tv_inbox_name" android:layout_width="wrap_content" android:layout_height="wrap_content" android:textSize="18sp" android:textColor="#333333" android:text="RecycleView+CardView" android:maxLines="1" android:ellipsize="end" app:layout_constraintTop_toTopOf="@id/layout_content" app:layout_constraintBottom_toBottomOf="@id/layout_content" app:layout_constraintStart_toStartOf="@id/layout_content" app:layout_constraintEnd_toEndOf="@id/layout_content" /> androidx.constraintlayout.widget.ConstraintLayout> androidx.cardview.widget.CardView> androidx.constraintlayout.widget.ConstraintLayout> <LinearLayout android:layout_width="@dimen/dp_74" android:layout_height="@dimen/dp_105" android:layout_gravity="center_vertical" android:orientation="horizontal"> <TextView android:id="@+id/tv_Delete" android:layout_width="@dimen/dp_74" android:layout_height="match_parent" android:background="#ccf44336" android:text="Delete" android:gravity="center_horizontal" android:textSize="10sp" android:paddingTop="@dimen/dp_20" android:layout_gravity="center" android:textColor="#FFFFFF" app:drawableTopCompat="@drawable/ic_game_list_delete" /> LinearLayout> androidx.appcompat.widget.LinearLayoutCompat>- 1
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菜单+cardView滑出无边距
class SlideRecyclerView : RecyclerView { /**滑动的itemView */ private var mMoveView: ViewGroup? = null /**itemView中菜单控件宽度 */ private var mMenuWidth = 0 private var mVelocity: VelocityTracker? = null /**触碰时的首个横坐标 */ private var mFirstX = 0 /**触碰时的首个纵坐标 */ private var mFirstY = 0 /**触碰末次的横坐标 */ private var mLastX = 0 /**最小滑动距离 */ private var mTouchSlop = 0 private var mScroller: Scroller? = null private var group: ViewGroup? = null //主布局容器 /**是否正在水平滑动 */ private var mMoving = false /**是否由onInterceptTouchEvent（）方法拦截 */ private var mIntercepted = false constructor(context: Context?) : super(context!!) { init() } constructor(context: Context?, attrs: AttributeSet?) : super( context!!, attrs ) { init() } constructor(context: Context?, attrs: AttributeSet?, defStyle: Int) : super( context!!, attrs, defStyle ) { init() } private fun init() { mTouchSlop = ViewConfiguration.get(context).scaledTouchSlop mScroller = Scroller(context) } override fun onInterceptTouchEvent(e: MotionEvent): Boolean { val x = e.x.toInt() val y = e.y.toInt() addVelocityEvent(e) when (e.action) { MotionEvent.ACTION_DOWN -> { //若Scroller处于动画中，则终止动画 if (!mScroller!!.isFinished) { mScroller!!.abortAnimation() } mFirstX = x mFirstY = y mLastX = x //获取点击区域所在的itemView val view = findChildViewUnder(x.toFloat(), y.toFloat()) as ViewGroup? //在点击区域以外的itemView开着菜单，则关闭菜单并拦截该次触碰事件 if (mMoveView != null && view !== mMoveView && mMoveView!!.scrollX != 0) { closeMenu() mIntercepted = true return true } mMoveView = view //拿到主布局 if (mMoveView?.getChildAt(0) != null && mMoveView!!.childCount == 2) group = mMoveView!!.getChildAt(0) as ViewGroup //获取itemView中菜单的宽度（规定itemView中为两个子View） mMenuWidth = if (mMoveView != null && mMoveView!!.childCount == 2) { mMoveView!!.getChildAt(1).width } else { -1 } } MotionEvent.ACTION_MOVE -> { mVelocity!!.computeCurrentVelocity(1000) val velocityX = Math.abs(mVelocity!!.xVelocity).toInt() val velocityY = Math.abs(mVelocity!!.yVelocity).toInt() val moveX = Math.abs(x - mFirstX) val moveY = Math.abs(y - mFirstY) //满足如下条件其一则判定为水平滑动： //1、水平速度大于竖直速度,且水平速度大于最小速度 //2、水平位移大于竖直位移,且大于最小移动距离 //必需条件：itemView菜单栏宽度大于0，且recyclerView处于静止状态（即并不在竖直滑动） val isHorizontalMove = (Math.abs(velocityX) >= MINIMUM_VELOCITY && velocityX > velocityY || moveX > moveY && moveX > mTouchSlop) && mMenuWidth > 0 && scrollState == 0 if (isHorizontalMove) { mIntercepted = true return true } } MotionEvent.ACTION_UP, MotionEvent.ACTION_CANCEL -> { setCardViewStatus(false) releaseVelocity() //itemView以及其子view触发点击事件，菜单未关闭则直接关闭 closeMenuNow() } else -> { } } return super.onInterceptTouchEvent(e) } override fun onTouchEvent(e: MotionEvent): Boolean { val x = e.x.toInt() val y = e.y.toInt() addVelocityEvent(e) when (e.action) { MotionEvent.ACTION_DOWN -> //若是通过onInterceptTouchEvent（）方法ACTION_DOWN拦截而来的，则丢弃此次事件 if (mIntercepted) { mIntercepted = false if (!mMoving) setCardViewStatus(false) return false } MotionEvent.ACTION_MOVE -> { mVelocity!!.computeCurrentVelocity(1000) val velocityX = Math.abs(mVelocity!!.xVelocity).toInt() val velocityY = Math.abs(mVelocity!!.yVelocity).toInt() val moveX = Math.abs(x - mFirstX) val moveY = Math.abs(y - mFirstY) val isHorizontalMove = mIntercepted || mMoving || (Math.abs(velocityX) >= MINIMUM_VELOCITY && velocityX > velocityY || moveX > moveY && moveX > mTouchSlop) && mMenuWidth > 0 && scrollState == 0 if (isHorizontalMove) { val dx = mLastX - x //让itemView在规定区域随手指移动 if (mMoveView!!.scrollX + dx in 0..mMenuWidth) { mMoveView!!.scrollBy(dx, 0) } setCardViewStatus(true) mLastX = x //设置正处于水平滑动状态 mMoving = true mIntercepted = false return true } } MotionEvent.ACTION_UP, MotionEvent.ACTION_CANCEL -> { if (mMoving) { mMoving = false mVelocity!!.computeCurrentVelocity(1000) val scrollX = mMoveView!!.scrollX //若速度大于正方向最小速度，则关闭菜单栏；若速度小于反方向最小速度，则打开菜单栏 //若速度没到判断条件，则对菜单显示的宽度进行判断打开/关闭菜单 if (mVelocity!!.xVelocity >= MINIMUM_VELOCITY) { mScroller!!.startScroll(scrollX, 0, -scrollX, 0, Math.abs(scrollX)) setCardViewStatus(false) } else if (mVelocity!!.xVelocity < -MINIMUM_VELOCITY) { val dx = mMenuWidth - scrollX mScroller!!.startScroll(scrollX, 0, dx, 0, Math.abs(dx)) setCardViewStatus(true) } else if (scrollX > mMenuWidth / 2) { val dx = mMenuWidth - scrollX mScroller!!.startScroll(scrollX, 0, dx, 0, Math.abs(dx)) setCardViewStatus(true) } else { mScroller!!.startScroll(scrollX, 0, -scrollX, 0, Math.abs(scrollX)) setCardViewStatus(false) } invalidate() } else if (mMoveView != null && mMoveView!!.scrollX != 0) { //若不是水平滑动状态，菜单栏开着则关闭 closeMenu() } releaseVelocity() } else -> { } } return super.onTouchEvent(e) } private fun setCardViewStatus(isOpen: Boolean) {//item滑动action的状态，根据菜单是否关闭等修改cardview的边距，同理其他内部控件一样 group?.forEach { if (it is CardView) { val lp: ConstraintLayout.LayoutParams = it.layoutParams as ConstraintLayout.LayoutParams lp.rightMargin = if (isOpen) 0 else PxUtils.dpToPx(16, it.context) it.layoutParams = lp } } } override fun computeScroll() { if (mScroller!!.computeScrollOffset()) { if (isInWindow(mMoveView)) { mMoveView!!.scrollTo(mScroller!!.currX, 0) invalidate() } else { //若处于动画的itemView滑出屏幕，则终止动画，并让其到达结束点位置 mScroller!!.abortAnimation() mMoveView!!.scrollTo(mScroller!!.finalX, 0) } } } /** * 使用Scroller关闭菜单栏 */ fun closeMenu() { mScroller!!.startScroll(mMoveView!!.scrollX, 0, -mMoveView!!.scrollX, 0, 300) invalidate() } /** * 即刻关闭菜单栏 */ fun closeMenuNow() { if (mMoveView != null && mMoveView!!.scrollX != 0) { mMoveView!!.scrollTo(0, 0) } } /** * 获取VelocityTracker实例，并为其添加事件 * @param e 触碰事件 */ private fun addVelocityEvent(e: MotionEvent) { if (mVelocity == null) { mVelocity = VelocityTracker.obtain() } mVelocity!!.addMovement(e) } /** * 释放VelocityTracker */ private fun releaseVelocity() { if (mVelocity != null) { mVelocity!!.clear() mVelocity!!.recycle() mVelocity = null } } /** * 判断该itemView是否显示在屏幕内 * @param view itemView * @return isInWindow */ private fun isInWindow(view: View?): Boolean { if (layoutManager is LinearLayoutManager) { val manager = layoutManager as LinearLayoutManager? val firstPosition = manager!!.findFirstVisibleItemPosition() val lastPosition = manager.findLastVisibleItemPosition() val currentPosition = manager.getPosition(view!!) return currentPosition in firstPosition..lastPosition } return true } companion object { /**最小速度 */ private const val MINIMUM_VELOCITY = 500 } }- 1
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本篇文章到此结束，有问题欢迎批评指正
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- 原文地址：https://blog.csdn.net/Tobey_r1/article/details/126346366
