Android Kotlin：在片段中创建RecyclerView

Question

我是Android开发的新手，但我坚持要零碎地创建RecyclerView。

我创建了2个适配器（对于Tablayout下的多个片段，创建了AdaptorAll.kt，对于要在其上创建recyclerview的片段创建了MainAdapter.kt，但无法调用MainAdapter.kt。MainActivity.kt调用AdapterAll.kt，但不调用MainAdapter.kt。我相信这就是为什么我可以使用片段创建Tablayout，但是不能在片段上创建Recyclerview的原因。

非常感谢！

代码如下：

MainActivity.kt

import controller.AdapterAll
import controller.MainAdapter
import kotlinx.android.synthetic.main.activity_main.*

class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        viewPager.adapter = AdapterAll(supportFragmentManager)
        tabLayoutId.setupWithViewPager(viewPager)

        tabLayoutId.setTabTextColors(Color.GRAY, Color.parseColor("white"))

        recyclerView_main.layoutManager = LinearLayoutManager(this)
        recyclerView_main.adapter = MainAdapter()
    }
}

AdapterAll.kt

class AdapterAll(fragmentManager: FragmentManager): 
    FragmentPagerAdapter(fragmentManager) {
    override fun getItem(position: Int): Fragment {
        when (position) {
            0 -> return Function1()
            1 -> return Function2()
            2 -> return Function3()
            3 -> return Function4()
            4 -> return Function5()
            5 -> return Function6()
            6 -> return Function7()
        }
        return Function1()
    }

    override fun getCount(): Int {
        return 7
    }

    override fun getPageTitle(position: Int): CharSequence? {
        when (position) {
            0 -> return "Function 1"
            1 -> return "Function 2"
            2 -> return "Function 3"
            3 -> return "Function 4"
            4 -> return "Function 5"
            5 -> return "Function 6"
            6 -> return "Function 7"
        }
        return null
    }
}

MainAdapter.kt

class MainAdapter: RecyclerView.Adapter<CustomViewHolder>() {


    override fun getItemCount(): Int {
        return 10
    }

    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): CustomViewHolder {
        val layoutInflater = LayoutInflater.from(parent.context)
        val cellForRow = layoutInflater.inflate(R.layout.fragment_function1, parent, false)
        return CustomViewHolder(cellForRow)
    }

    override fun onBindViewHolder(holder: CustomViewHolder, position: Int) {
        holder.view.textView_video_title.text = "123"
    }

}

class CustomViewHolder(val view: View): RecyclerView.ViewHolder(view) {

}

Answer 1

您的适配器还可以。如果我没有记错的话，您想在片段中使用recyclerView，但是为什么要在Activity中创建recyclerView。在您的片段中创建一个recyclerView，并在recyclerView中设置MainAdapter.kt。

class FragmentOne : Fragment() {

override fun onCreateView(
    inflater: LayoutInflater, container: ViewGroup?,
    savedInstanceState: Bundle?
): View? {
    val view = inflater.inflate(R.layout.fragment_blank, container, false)

    view.recyclerView.layoutManager = LinearLayoutManager(activity)
    view.recyclerView.adapter = MainAdapter()


    return view
}}