【PageLayout】非常简单的一键切换加载-空数据-错误页，支持自定义

PageLayout.Builder(this)
                .initPage(ll_default)
                .setOnRetryListener(object : PageLayout.OnRetryClickListener{
                    override fun onRetry() {
                        loadData()
                    }

                })
                .create()

PageLayout.Builder(this)
                .initPage(ll_demo)
                .setLoading(R.layout.layout_loading_demo)
                .setEmpty(R.layout.layout_empty_demo)
                .setError(R.layout.layout_error_demo,R.id.tv_page_error_demo,object : PageLayout.OnRetryClickListener{
                    override fun onRetry() {
                        loadData()
                    }
                })
                .setEmptyDrawable(R.drawable.pic_empty)
                .setErrorDrawable(R.drawable.pic_error)
                .create()

/**
        * set target view for root
        */
       fun initPage(targetView: Any): Builder {
           var content: ViewGroup? = null
           when (targetView) {
               is Activity -> {    //如果是Activity，获取到android.R.content
                   mContext = targetView
                   content = (mContext as Activity).findViewById(android.R.id.content)
               }
               is Fragment -> {    //如果是Fragment获取到parent
                   mContext = targetView.activity!!
                   content = (targetView.view)?.parent as ViewGroup
               }
               is View -> {        //如果是View，也取到parent
                   mContext = targetView.context
                   try {
                       content = (targetView.parent) as ViewGroup
                   } catch (e: TypeCastException) {
                   }
               }
           }
           val childCount = content?.childCount
           var index = 0
           val oldContent: View
           if (targetView is View) {   //如果是某个线性布局或者相对布局时，遍历它的孩子，找到对应的索引，记录下来
               oldContent = targetView
               childCount?.let {
                   for (i in 0 until childCount) {
                       if (content!!.getChildAt(i) === oldContent) {
                           index = i
                           break
                       }
                   }
               }

           } else {    //如果是Activity或者Fragment时，取到索引为第一个的View
               oldContent = content!!.getChildAt(0)
           }
           mPageLayout.mContent = oldContent   //给PageLayout设置contentView
           mPageLayout.removeAllViews()    
           content?.removeView(oldContent)     //将本身content移除，并且把PageLayout添加到DecorView中去
           val lp = oldContent.layoutParams
           content?.addView(mPageLayout, index, lp)
           mPageLayout.addView(oldContent)
           initDefault()   //设置默认状态布局
           return this
       }

fun setError(errorView: Int, errorClickId: Int, onRetryClickListener: OnRetryClickListener)