前言

我们日常的需求基本上都是图片的轮播,而在一些特殊需求,例如用于展览的的数据大屏,又想展示图片又想展示视频,本文将利用第三方库com.youth.play.banner轮播控件实现图片和视频混合轮播的效果,自动+手动滑动,无限循环,视频自动播放。

其中图片使用Glide图片加载库,视频使用GSYVideoPlayer播放器。

第三方库移步:【Android】常用的第三方开源库汇总


一、实现效果

在这里插入图片描述在这里插入图片描述

二、具体实现

1. 导入依赖

implementation 'com.youth.banner:banner:2.1.0'
implementation 'com.github.bumptech.glide:glide:4.11.0'
implementation 'com.shuyu:GSYVideoPlayer:7.1.8'

2. 布局

主页面:

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent">
    
    <com.youth.banner.Banner
        android:id="@+id/banner"
        android:layout_width="match_parent"
        android:layout_height="300dp"
        android:layout_margin="10dp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent" />
        
</androidx.constraintlayout.widget.ConstraintLayout>

这里没有使用库里面写好的指示器Indicator,需要的可以自行查看文档使用:Banner

3. Banner基础配置


// 添加生命周期管理,确保在适当的生命周期内开始和停止轮播
banner.addBannerLifecycleObserver(this)
    .setAdapter(adapter,true) //是否开启无限循环
    .setLoopTime(loopTime) //轮播时间
    
// 设置轮播图的点击事件监听器
banner.addOnPageChangeListener(object :
    OnPageChangeListener {
    /**
     * 滑动中的监听,当页面在滑动的时候会调用此方法,在滑动被停止之前,此方法会一直得到调用
     */
    override fun onPageScrolled(position: Int, positionOffset: Float, positionOffsetPixels: Int) {
    }

    /**
     * 监听滑动到对应索引值的页面,第一个页面不执行
     */
    override fun onPageSelected(position: Int) {
    }
    /**
     * 滑动状态监听
     */
    override fun onPageScrollStateChanged(state: Int) {
    }
})

Banner支持图片的无限循环,可以选择性打开。我们需要在其中插入视频的播放,就需要先了解其无限循环的处理机制。

4. Banner无限循环机制

无限循环主要有两种实现,一种是设置页面总数设置得很大,一直滑不到底,这不是真正的无限循环,是一种伪循环,性能较低。另外一种就是接下来要说的,Banner的无限循环,它是通过ViewPage2去实现的,在原有页面的基础上左右各添加一个页面,滑动到最后一页跳转到第二页,滑动到第一页跳转到倒数第二页。

在这里插入图片描述

这里为什么要多两个页面呢?一个目的是为了滑动到中间时,有一半是原页面,有一半是新页面。第二个目的是为了有滑动的效果,不会出现跳动。

首先,ViewPage2有三个监听方法:

onPageScrolled :滑动中的监听,当页面在滑动的时候会调用此方法,在滑动被停止之前,此方法会一直得到调用
onPageSelected :滑动或移动(左右滑动、点击指示器跳转)到某一页面时的监听,第一个页面不执行
onPageScrollStateChanged,滑动状态的监听

按理说,在滑动到最后一页时,我们只需要在 onPageSelected 中使用 setCurrentItem 跳转到第一页(总页数的第二页)即可,但是 onPageSelected 在滑动动画还没结束的时候就已经被调用了,此时调用 setCurrentItem 会强制取消当前正在进行的滑动动画并跳转,导致页面跳动不平滑。

所以可以这样去解决这一问题:
(1)先在 onPageSelected 中记录被选中的页面
(2)再在 onPageScrollStateChanged 判断当前动画是否结束,当动画结束时再去调用setCurrentItem方法跳转

我们查看Banner里面的源码也是这样处理无限循环的:
在这里插入图片描述

这里需要格外注意页面的下标,一个页面有两种下标,一个真实下标 realPosition,一个物理下标 position。同理,页面总数量、根据下标获取数据也是一样的逻辑。
在这里插入图片描述
以上面的图为例,下标如下

页面positionrealPosition
第一页02(最后一页)
第二页10
第三页21
第四页32
最后一页40 (第一页)
    /**
     * 获取真正的位置
     *
     * @param isIncrease 首尾是否有增加
     * @param position  当前位置
     * @param realCount 真实数量
     * @return
     */
    public static int getRealPosition(boolean isIncrease, int position, int realCount) {
        if (!isIncrease) {
            return position;
        }
        int realPosition;
        if (position == 0) {
            realPosition = realCount - 1;
        } else if (position == realCount + 1) {
            realPosition = 0;
        } else {
            realPosition = position - 1;
        }
        return realPosition;
    }

5. 轮播适配器

//轮播数据
private val resourcesList by lazy{
        arrayListOf<PlayResourcesBean>().apply {
            add(PlayResourcesBean(isImg = true, title = "图片", url = "https://upload-images.jianshu.io/upload_images/5809200-a99419bb94924e6d.jpg?imageMogr2/auto-orient/strip%7CimageView2/2/w/1240"))
            add(PlayResourcesBean(isImg = true,title = "图片",url = "https://s10.mogucdn.com/mlcdn/c45406/170831_479g0ifl6f2i313feb5ech46kek21_778x440.jpg"))
            add(PlayResourcesBean(isImg = false, title = "视频",url = "https://media.w3.org/2010/05/sintel/trailer.mp4"))
            add(PlayResourcesBean(isImg = true,title = "图片",url = "https://s10.mogucdn.com/mlcdn/c45406/170831_7gee6d620i774ec3l5bfh55cfaeab_778x440.jpg"))
            add(PlayResourcesBean(isImg = false,title = "视频",url = "https://media.w3.org/2010/05/sintel/trailer.mp4"))
            add(PlayResourcesBean(isImg = true,title = "图片",url = "https://s10.mogucdn.com/mlcdn/c45406/170829_59ia6fd99ghkdkd9603kblha21h5b_778x440.jpg"))
            add(PlayResourcesBean(isImg = true,title = "图片",url = "https://img.zcool.cn/community/01233056fb62fe32f875a9447400e1.jpg"))
            add(PlayResourcesBean(isImg = false,title = "视频",url = "https://media.w3.org/2010/05/sintel/trailer.mp4"))
        }
    }

private val adapter by lazy{
    PlayAdapter(this,resourcesList, this)
}


@Keep
data class PlayResourcesBean(
    /**
     * 图片或者视频路径
     */
    val url: String? = "",
    val isImg:Boolean,
    val title: String?=""
)

PlayAdapter需要继承BannerAdapter,处理两种不同类型的item(图片item和视频item)

class PlayAdapter(private val mContext: Context, private val dataList: ArrayList<PlayResourcesBean>,
                  private val mActivity: MainActivity
):
    BannerAdapter<PlayResourcesBean, RecyclerView.ViewHolder>(dataList) {

    private val mVHMap = HashMap<Int,RecyclerView.ViewHolder>()

    private val options by lazy {
        RequestOptions().priority(Priority.HIGH)
            .placeholder(R.mipmap.default_ic)
            .error(R.mipmap.default_ic)
    }

    companion object{
       //视频
       const val VIDEO = 1
        //图片
        const val IMAGE = 2
    }

    override fun onBindViewHolder(
        holder: RecyclerView.ViewHolder,
        position: Int,
        payloads: MutableList<Any>
    ) {
        super.onBindViewHolder(holder, position, payloads)

        val realPosition = getRealPosition(position)
        if (holder is VideoHolder){
            setVideo( holder, getData(realPosition),position,realPosition,realCount)
            mVHMap[position] = holder
        }else if(holder is ImageHolder){
            setImage(holder,getData(realPosition),realPosition,realCount)
            mVHMap[position] = holder
        }
    }

    override fun getItemViewType(position: Int): Int {
        //这里的position不是真实的坐标,获取数据需要转换
        return if (getData(getRealPosition(position)).isImg){
            IMAGE
        }else {
            VIDEO
        }
    }

    override fun onCreateHolder(parent: ViewGroup?, viewType: Int): RecyclerView.ViewHolder {
        val holder:RecyclerView.ViewHolder
        val from = LayoutInflater.from(mContext)
        if (viewType==VIDEO){
            val view=from.inflate(R.layout.play_item_video,parent,false)
            holder=VideoHolder(view)
        }else {
            val view=from.inflate(R.layout.play_item_image,parent,false)
            holder=ImageHolder(view)
        }

        return holder
    }

    private fun setImage(
        holder: ImageHolder,
        data: PlayResourcesBean,
        position: Int,
        size: Int
    ) {
        Glide.with(mContext)
            .load(data.url)
            .apply(options)
            .into(holder.image)

        holder.title.text=data.title?:""
        holder.numIndicator.text="${position+1}/$size"
    }

    private fun setVideo(
        holder: VideoHolder,
        data: PlayResourcesBean,
        position: Int,
        realPosition: Int,
        size: Int
    ) {
        holder.video.apply {
            setUp(data.url,true,mContext.externalCacheDir,null,"")
            titleTextView.visibility = View.GONE
            backButton.visibility = View.GONE
            fullscreenButton.visibility = View.GONE
            startButton.visibility = View.GONE


            //音频焦点冲突时是否释放
            isReleaseWhenLossAudio = true
            //禁止全屏
            isAutoFullWithSize = false
            //isStartAfterPrepared=true
            dismissControlTime=0
            isClickable=false
            isEnabled=false
            isLongClickable=false
            playPosition=position


            //禁止滑动
            setIsTouchWiget(false)
            setVideoAllCallBack(object :GSYSampleCallBack(){
                override fun onComplete(url: String?, vararg objects: Any?) {
                    super.onComplete(url, *objects)
                    mActivity.banner.isAutoLoop(true)
                    mActivity.banner.start()
                }

                override fun onPlayError(url: String?, vararg objects: Any?) {
                    super.onPlayError(url, *objects)
                    mActivity.banner.isAutoLoop(true)
                    mActivity.banner.start()
                }

                override fun onClickStop(url: String?, vararg objects: Any?) {
                    super.onClickStop(url, *objects)
                    mActivity.banner.isAutoLoop(true)
                    mActivity.banner.start()
                }

                override fun onPrepared(url: String?, vararg objects: Any?) {
                    super.onPrepared(url, *objects)

                }

                override fun onStartPrepared(url: String?, vararg objects: Any?) {
                    super.onStartPrepared(url, *objects)

                }
                override fun onAutoComplete(url: String?, vararg objects: Any?) {
                    super.onAutoComplete(url, *objects)
                    mActivity.banner.isAutoLoop(true)

                    //快速轮播到下一页
                    mActivity.banner.setLoopTime(100)
                    mActivity.banner.start()
                    mActivity.banner.setLoopTime(mActivity.loopTime)
                }
            })
        }

        holder.title.text=data.title?:""
        holder.numIndicator.text="${realPosition+1}/$size"

    }

    internal class VideoHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {
        val video: MyVideoPlayer
        val title: TextView
        val numIndicator:TextView
        init {
            video = itemView.findViewById(R.id.banner_vp)
            title = itemView.findViewById(R.id.video_title)
            numIndicator = itemView.findViewById(R.id.video_numIndicator)
        }
    }

    internal class ImageHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {
        val image: ImageView
        val title: TextView
        val numIndicator:TextView
        init {
            image = itemView.findViewById(R.id.banner_image)
            title = itemView.findViewById(R.id.image_title)
            numIndicator = itemView.findViewById(R.id.image_numIndicator)
        }
    }

    fun getVHMap(): HashMap<Int,RecyclerView.ViewHolder> {
        return mVHMap
    }

    override fun onBindView(
        holder: RecyclerView.ViewHolder?,
        data: PlayResourcesBean?,
        position: Int,
        size: Int
    ) {
    }


}

这里需要用一个HashMap去存储所有ViewHolder,以便后续控制视频自动播放,这里的key是物理下标,一个key对应一个页面,如果用realPosition作为key,不是一对一,容易产生value更新不及时。

6. 视频播放处理

GSYVideoPlayer 播放器的使用可以查看文档:GSYVideoPlayer

无限循环解决之后,就需要在轮播中自动播放视频,隐藏和关闭掉各种手动按钮和事件,需要对播放器进行改造(继承StandardGSYVideoPlayer),我是在翻看了它许多源码和github上的issues才得以解决。

class MyVideoPlayer(context: Context, attrs: AttributeSet?) : StandardGSYVideoPlayer(context,attrs){


    override fun changeUiToPreparingShow() {
        super.changeUiToPreparingShow()
        hide()
    }

    override fun changeUiToPauseShow() {
        super.changeUiToPauseShow()
        hide()
    }

    override fun changeUiToError() {
        super.changeUiToError()
        hide()
    }

    override fun changeUiToCompleteShow() {
        super.changeUiToCompleteShow()
        hide()
    }

    override fun changeUiToPlayingBufferingShow() {
        super.changeUiToPlayingBufferingShow()
        hide()
    }

    override fun changeUiToPrepareingClear() {
        super.changeUiToPrepareingClear()
        hide()
    }

    override fun changeUiToPlayingClear() {
        super.changeUiToPlayingClear()
        hide()
    }

    override fun changeUiToPauseClear() {
        super.changeUiToPauseClear()
        hide()
    }

    override fun changeUiToPlayingBufferingClear() {
        super.changeUiToPlayingBufferingClear()
        hide()
    }

    override fun changeUiToClear() {
        super.changeUiToClear()
        hide()
    }

    override fun changeUiToCompleteClear() {
        super.changeUiToCompleteClear()
        hide()
    }

    override fun changeUiToPlayingShow() {
        super.changeUiToPlayingShow()
        hide()

    }

    override fun changeUiToNormal() {
        super.changeUiToNormal()
        hide()
    }
    private fun hide() {
        setViewShowState(mTopContainer, INVISIBLE)
        setViewShowState(mBottomContainer, INVISIBLE)
        setViewShowState(mStartButton, INVISIBLE)
        setViewShowState(mLoadingProgressBar, INVISIBLE)
        setViewShowState(mThumbImageViewLayout, INVISIBLE)
        setViewShowState(mBottomProgressBar, INVISIBLE)
        setViewShowState(mLockScreen, GONE)
    }


    override fun onVideoPause() {
        super.onVideoPause()
        mPauseBeforePrepared=false //是否准备完成前调用了暂停,避免再次暂停
    }
    override fun touchDoubleUp() {
        //双击会暂停,重载清除
    }
}

StandardGSYVideoPlayer是GSYVideoPlayer中的一个标准样式的播放器,在视频准备、暂停、播放完成等等状态隐藏和关闭掉各种手动按钮和事件,设置mPauseBeforePrepared避免视频准备完成后自动暂停,重载touchDoubleUp清除掉原有的双击屏幕暂停视频的效果。

视频自动播放
接下来就是主要逻辑了,这里有几个关键点:

在轮播到视频时,将自动轮播关闭,同时播放视频
在视频播放错误、非正常完成时,暂停视频,同时继续轮播
在视频播放正常完成、手动滑动到下一页时,立即轮播到下一页

首先,就需要在MyVideoPlayer适配器中处理视频控件的各种监听事件(查看源码视频有各种状态):

setVideoAllCallBack(object :GSYSampleCallBack(){
    override fun onComplete(url: String?, vararg objects: Any?) {
        super.onComplete(url, *objects)
        mActivity.banner.isAutoLoop(true)
        mActivity.banner.start()
    }

    override fun onPlayError(url: String?, vararg objects: Any?) {
        super.onPlayError(url, *objects)
        mActivity.banner.isAutoLoop(true)
        mActivity.banner.start()
    }

    override fun onClickStop(url: String?, vararg objects: Any?) {
        super.onClickStop(url, *objects)
        mActivity.banner.isAutoLoop(true)
        mActivity.banner.start()
    }

    override fun onPrepared(url: String?, vararg objects: Any?) {
        super.onPrepared(url, *objects)

    }

    override fun onStartPrepared(url: String?, vararg objects: Any?) {
        super.onStartPrepared(url, *objects)

    }
    override fun onAutoComplete(url: String?, vararg objects: Any?) {
        super.onAutoComplete(url, *objects)
        mActivity.banner.isAutoLoop(true)

        //设置轮播时间,立即轮播到下一页
        mActivity.banner.setLoopTime(100)
        mActivity.banner.start()
        mActivity.banner.setLoopTime(mActivity.loopTime)
    }
})

其次,在Activity中设置任务,在页面切换时通过之前保存的ViewHolder去执行视频播放或者暂停的任务:

private val taskHandler by lazy{
	Handler(Looper.getMainLooper())
}
val task = Runnable { 
    //可能是首尾切换页,两个页面循环跳转
    if(adapter.getVHMap().containsKey(currentPos)){
        if(adapter.getVHMap()[currentPos] is PlayAdapter.VideoHolder){
            val holder = (adapter.getVHMap()[currentPos] as PlayAdapter.VideoHolder)
            GSYVideoManager.onPause()
            holder.video.startPlayLogic()
            banner.isAutoLoop(true)
            banner.stop()
            banner.isAutoLoop(false)
        }else{
            GSYVideoManager.onPause()

            banner.isAutoLoop(true)
            banner.start()
        }
    }else{
        GSYVideoManager.onPause()
        banner.isAutoLoop(true)
        banner.start()
    }
}

// 设置轮播图的点击事件监听器
banner.addOnPageChangeListener(object :
    OnPageChangeListener {

    /**
     * 滑动中的监听,当页面在滑动的时候会调用此方法,在滑动被停止之前,此方法会一直得到调用
     */
    override fun onPageScrolled(position: Int, positionOffset: Float, positionOffsetPixels: Int) {

    }

    /**
     * 监听滑动到对应索引值的页面,第一个页面不执行
     */
    override fun onPageSelected(position: Int) {
        if (position == banner.realCount - 1) {
            currentPos=banner.realCount
        } else if (position == 0) {
            currentPos = 1
        } else {
            currentPos = position + 1
        }
    }
    /**
     * 滑动状态监听
     */
    override fun onPageScrollStateChanged(state: Int) {
        // Banner跳转之后再去控制视频播放
        if (state == ViewPager2.SCROLL_STATE_IDLE) {
            if (banner.isInfiniteLoop) {
                taskHandler.post(task)
            }
        }
    }
})

任务一定要在onPageScrollStateChanged中去执行,这时候特殊的两个页面已经跳转完成了,只会执行一次任务,否则执行两个异步任务会导致一个视频播放一个视频暂停,两个异步没有固定的执行顺序,出现视频没有画面但是有声音的问题。

完整的Activity代码:

class MainActivity:AppCompatActivity() {
    val loopTime=6000L

    //列表+前后两页过渡页的坐标
    private var currentPos= 1

    private val taskHandler by lazy{
        Handler(Looper.getMainLooper())
    }

    private val adapter by lazy{
        PlayAdapter(this,resourcesList, this)
    }

    private val resourcesList by lazy{
        arrayListOf<PlayResourcesBean>().apply {
            add(PlayResourcesBean(isImg = true, title = "图片", url = "https://upload-images.jianshu.io/upload_images/5809200-a99419bb94924e6d.jpg?imageMogr2/auto-orient/strip%7CimageView2/2/w/1240"))
            add(PlayResourcesBean(isImg = true,title = "图片",url = "https://s10.mogucdn.com/mlcdn/c45406/170831_479g0ifl6f2i313feb5ech46kek21_778x440.jpg"))
            add(PlayResourcesBean(isImg = false, title = "视频",url = "https://media.w3.org/2010/05/sintel/trailer.mp4"))
            add(PlayResourcesBean(isImg = true,title = "图片",url = "https://s10.mogucdn.com/mlcdn/c45406/170831_7gee6d620i774ec3l5bfh55cfaeab_778x440.jpg"))
            add(PlayResourcesBean(isImg = false,title = "视频",url = "https://media.w3.org/2010/05/sintel/trailer.mp4"))
            add(PlayResourcesBean(isImg = true,title = "图片",url = "https://s10.mogucdn.com/mlcdn/c45406/170829_59ia6fd99ghkdkd9603kblha21h5b_778x440.jpg"))
            add(PlayResourcesBean(isImg = true,title = "图片",url = "https://img.zcool.cn/community/01233056fb62fe32f875a9447400e1.jpg"))
            add(PlayResourcesBean(isImg = false,title = "视频",url = "https://media.w3.org/2010/05/sintel/trailer.mp4"))
        }
    }
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        initBanner()
    }

    private fun initBanner() {

        // 添加生命周期管理,确保在适当的生命周期内开始和停止轮播
        banner.addBannerLifecycleObserver(this)
            .setAdapter(adapter,true) //是否开启无限循环
            .setLoopTime(loopTime) //轮播时间


        // 设置轮播图的点击事件监听器
        banner.addOnPageChangeListener(object :
            OnPageChangeListener {

            /**
             * 滑动中的监听,当页面在滑动的时候会调用此方法,在滑动被停止之前,此方法会一直得到调用
             */
            override fun onPageScrolled(position: Int, positionOffset: Float, positionOffsetPixels: Int) {

            }

            /**
             * 监听滑动到对应索引值的页面,第一个页面不执行
             */
            override fun onPageSelected(position: Int) {
                if (position == banner.realCount - 1) {
                    currentPos=banner.realCount
                } else if (position == 0) {
                    currentPos = 1
                } else {
                    currentPos = position + 1
                }
            }
            /**
             * 滑动状态监听
             */
            override fun onPageScrollStateChanged(state: Int) {
                // Banner跳转之后再去控制视频播放
                if (state == ViewPager2.SCROLL_STATE_IDLE) {
                    if (banner.isInfiniteLoop) {
                        taskHandler.post(task)
                    }
                }
            }
        })

        //重新设置banner数据
        //banner.setDatas(resourcesList)

    }


    val task = Runnable {
        //可能是首尾切换页,两个页面循环跳转
        if(adapter.getVHMap().containsKey(currentPos)){
            if(adapter.getVHMap()[currentPos] is PlayAdapter.VideoHolder){
                val holder = (adapter.getVHMap()[currentPos] as PlayAdapter.VideoHolder)
                GSYVideoManager.onPause()
                holder.video.startPlayLogic()
                banner.isAutoLoop(true)
                banner.stop()
                banner.isAutoLoop(false)
            }else{
                GSYVideoManager.onPause()

                banner.isAutoLoop(true)
                banner.start()
            }
        }else{
            GSYVideoManager.onPause()
            banner.isAutoLoop(true)
            banner.start()
        }
    }

    override fun onResume() {
        super.onResume()
        taskHandler.post(task)
    }


    override fun onPause() {
        super.onPause()
        GSYVideoManager.onPause()
    }
    override fun onDestroy() {
        super.onDestroy()
        GSYVideoManager.releaseAllVideos()
        //移除数据绑定,否则第二次设置适配器出错
        banner.destroy()
    }

}

7. 完整源码

到这就完结撒花了🎉,完整代码我已上传github,需要的可以自行pull:https://github.com/FullCourage/BannerPlayer


总结

解决jar包的一些底层问题,不仅要知道原理,还要学会从源码中了解它的执行逻辑。

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