使用Presenter的Android TV leanback DetailsS​​upportFragment不会让光标在DPad上向下移动吗？

Question

我正在使用Leanback库在示例代码中显示节目的详细信息。我用DetailsS​​upportFragment扩展了我的片段，并使用Presenter显示了细节。 我发现的问题是，当广告内容描述行超过2条时，通过按DPad向下按钮，光标移动正确地向下移动到了下一行，但是如果小于或等于2，光标将移至右边的内容（在我的图标中案件）。

这是我的示例代码：

class MyDetailsFragment : DetailsSupportFragment() {

private var mySelector: ClassPresenterSelector? = null
private var myRow: DetailsOverviewRow? = null
private var myAdapter: SparseArrayObjectAdapter? = null

override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        super.onViewCreated(view, savedInstanceState)
/// some code to load data///

var myPresenter = CustomFullWidthDetailsOverviewRowPresenter(myData, CustomPresenter(), DetailsOverviewLogoPresenter()) ;

mySelector?.addClassPresenter(DetailsOverviewRow::class.java, myPresenter)
myRow = DetailsOverviewRow(myData.data)
myAdapter.set(1, myRow)

/// other code 
}

}


//Custom Presenter which sets title and description
class CustomPresenter : Presenter() {
override fun onCreateViewHolder(parent: ViewGroup): CbsAbstractDetailsDescriptionPresenter.ViewHolder {
/// returns view holder
return ViewHolder(v)
}

override fun onBindViewHolder(viewHolder: Presenter.ViewHolder, item: Any) {
// setting views here
}
}


class CustomFullWidthDetailsOverviewRowPresenter(myData: MyDataType, myPresenter: Presenter, logoPresenter: DetailsOverviewLogoPresenter): FullWidthDetailsOverviewRowPresenter {

override fun onLayoutOverviewFrame(viewHolder: FullWidthDetailsOverviewRowPresenter.ViewHolder,
                                       oldState: Int, logoChanged: Boolean) {
// some code //
}

}

注意：我没有任何代码来处理DPad按钮事件。只需使用ScrollingMovementMethod（）设置滚动运动即可。