//為展示在屏幕上的彈幕數(shù)據(jù) private val mDanMuList = LinkedList<BulletChatDetail>()
//屏幕中展示的彈幕數(shù)據(jù) private val mVisibleDanMuList = LinkedList<BulletChatDetail>()
fun enqueueDanMuList(danMuList: List<BulletChatDetail>?) {
    danMuList?.forEach {         
	if (this.mDanMuList.contains(it).not()) {
            this.mDanMuList.add(it)
        }
    }    
	if (mWidth == 0) {
        viewTreeObserver.addOnGlobalLayoutListener(object :
                ViewTreeObserver.OnGlobalLayoutListener {
            override fun onGlobalLayout() {
                mWidth = measuredWidth                
				viewTreeObserver.removeOnGlobalLayoutListener(this)

                if (mIsRunning.get().not()) {
                    mDanMuList.poll()?.apply {                       
					//這里是用來處理布局的交替工作，前面分析有說明                         					                           mVisibleDanMuList.add(this)
                        createDanMuItemView(this)
                    }                
				}
            }
        })
    } else {
        if (mIsRunning.get().not()) {
            mDanMuList.poll()?.apply {                 
			//這里是用來處理布局的交替工作，前面分析有說明                 
			mVisibleDanMuList.add(this)
            createDanMuItemView(this)
            }        
			}
    }
}

class DanMuItemView @JvmOverloads constructor(
        context: Context, attrs: AttributeSet? = null, defStyleAttr: Int = 0 ) : LinearLayoutCompat(context, attrs, defStyleAttr) {

    var danMu: BulletChatDetail? = null     
	private val mBinding: DanmuItemBinding      
	init {
        mBinding = DanmuItemBinding.inflate(
                LayoutInflater.from(context), this, true         )
    }

    fun setDanMuEntity(danmu: BulletChatDetail?) {
        this.danMu = danmu
        mBinding.tvDanMuItem.text = danmu?.bulletChat            	  	 mBinding.ivDanMuItem.setCircleImageUrl(danmu?.userLogo?.toCompleteImageUrl(3))
        measure(0, 0)
    }
}

private fun createDanMuItemView(DanMu: BulletChatDetail) {
    val danMuItemView = DanMuItemView(context).apply {         
	setDanMuEntity(DanMu)
    }     //這里將布局添加之后，默認便宜到屏幕右側(cè)出屏幕，造成布局總是從右??移動到??左的效果。    
	val param = LayoutParams(danMuItemView.measuredWidth, danMuItemView.measuredHeight)
    param.gravity = Gravity.CENTER_VERTICAL    
	param.leftMargin = mWidth     
	startDanMuAnimate(danMuItemView)
    addView(danMuItemView, param)
}

val targetSpeedPxPerSecond = 120.0f // 你想要的目標速度，單位是像素每秒 
val totalTranslateX = ((mWidth + danMuItemView.measuredWidth)).toFloat()
val duration = (totalTranslateX / targetSpeedPxPerSecond * 1000).toLong() // 轉(zhuǎn)換為毫秒
var isInit = false 
danMuItemView.animate()
       //注意這邊設置的便宜量是容器布局的寬度+彈幕item布局的寬度，這樣就確保滾動值剛好是從屏幕右側(cè)外到屏幕左側(cè)外         .translationXBy(-totalTranslateX)
        .setDuration(duration)
        .setInterpolator(LinearInterpolator())
        .setUpdateListener {              
		val danMuTranslateX =(mWidth + danMuItemView.measuredWidth) * (it.animatedValue as Float)
        //這里是關鍵，用來確保每個item布局的間距一致，判斷如果滾動進入屏幕的距離剛好是自身+20dp，也就是剛好空出來了20dp之后，緊接著下一個彈幕布局開始添加并動起來。             
			if (danMuTranslateX >= danMuItemView.measuredWidth +
                    DensityUtils.dp2px(15f) && isInit.not()) {
                isInit = true                
				if (mDanMuList.size == 0) {
                    mHasStopRun = true                 
					}else{
                    mHasStopRun = false                    
					mDanMuList.poll()?.apply {                     
					mVisibleDanMuList.add(this)
                        createDanMuItemView(this)
                    }                
				}
            }
        }         
		.setListener(object : AnimatorListenerAdapter() {
            override fun onAnimationEnd(animation: Animator) {
                super.onAnimationEnd(animation)
                if (mIsRunning.get().not()) {
                    mIsRunning.set(true)
                }
                //很重要，在動畫結(jié)束，也就是布局從屏幕移除之后，切記從布局中移除掉，                 
				//并且進行一波數(shù)據(jù)交替，方便實現(xiàn)無線循環(huán)                
				danMuItemView.danMu?.let {                    
				mVisibleDanMuList.remove(it)
                    mDanMuList.add(it)
                }                
				YzLog.e("mHasStopRun->>>>${mHasStopRun}")
                if (mHasStopRun) {
                    createDanMu()
                }else{
                    removeView(danMuItemView)
                }
            }
        }).start()