Question

点击后，我终止了应用程序而且我不知道在哪里必须输入适配器或中的点击顺序 RecyclerView的片段 Mainadapter.kt

class ContentAdapter(
    private val activity: MainActivity, 
    private var listOfData: ArrayList<MainMarketTickClass>
) : RecyclerView.Adapter<ContentAdapter.ViewHolder>(), View.OnClickListener {
    override fun onClick(v: View?) {
        val manager = activity.supportFragmentManager
        val transaction = manager.beginTransaction()
        val trs = AddCar()
        transaction.add(android.R.id.content, trs, "IndividualBook")
        transaction.addToBackStack(null)
        transaction.commit()
        var heroActivity: MainActivity = activity

    }

    override fun getItemCount(): Int = listOfData.size

    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
        var inf = ViewHolder(LayoutInflater.from(parent!!.context).inflate(R.layout.maintick, parent, false))
        return inf

    }

    override fun onBindViewHolder(holder: ViewHolder, position: Int) {
        holder!!.bind(listOfData)
        holder.itemView.MainImage.setOnClickListener(this)
    }

    class ViewHolder(itemView: View?) : RecyclerView.ViewHolder(itemView) {
        fun bind(listOfData: ArrayList<MainMarketTickClass>) {
            val dataListin2 = listOfData[adapterPosition]
            itemView.textView.text = dataListin2.title
        }
    }

RecyclerView片段

class MainMarket : Fragment() {
    var ITEMSList = ArrayList<MainMarketTickClass>()

    companion object {
        fun newInstance(): Fragment {
            var fb: MainMarket = MainMarket()
            return fb
        }
    }

    override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
        var inf = inflater!!.inflate(R.layout.main_marker, container, false)
        return inf
    }

    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        ITEMSList.add(MainMarketTickClass("123"))
        ITEMSList.add(MainMarketTickClass(" 123"))
        ITEMSList.add(MainMarketTickClass("123"))

        var adapter = ContentAdapter(MainActivity(), ITEMSList)
        list.adapter = adapter
        list.layoutManager = LinearLayoutManager(this.context, LinearLayoutManager.VERTICAL, false)
    }
}

我在OnClick fun FATAL EXCEPTION中有一些错误

Answer 1

我建议您使用与在适配器中使用单击侦听器事务不同的方法。

这是Adapter

class ContentAdapter constructor(private val activity: MainActivity, private var listOfData: ArrayList<MainMarketTickClass>, val listener: ContentListener) : RecyclerView.Adapter<ContentAdapter.ViewHolder>() {

    override fun getItemCount(): Int = listOfData.size
    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
        var inf = ViewHolder(LayoutInflater.from(parent!!.context).inflate(R.layout.maintick, parent, false))
        return inf

    }

    override fun onBindViewHolder(holder: ViewHolder, position: Int) {
        holder.bind(listOfData, listener)
    }

    class ViewHolder(itemView: View?) : RecyclerView.ViewHolder(itemView) {

        fun bind(listOfData: ArrayList<MainMarketTickClass>, listener: ContentListener) {
            val dataListin2 = listOfData[adapterPosition]

            itemView.textView.text = dataListin2.title

            // this is the click listener. It calls the onItemClicked interface method implemented in the Activity
            itemView.setOnClickListener {
                listener.onItemClicked(listOfData.get(adapterPosition))
            }
        }
    }

    public interface ContentListener {
        fun onItemClicked(item: MainMarketTickClass)
    }

}

这是MainActivity

class MainMarket: Fragment(), ContentAdapter.ContentListener {

var ITEMSList = ArrayList<MainMarketTickClass>()

companion object {
   fun newInstance():Fragment{

       var fb : MainMarket = MainMarket()
       return fb
   }
}


override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
    var inf = inflater!!.inflate(R.layout.main_marker,container,false)
    return inf
}

override fun onViewCreated(view: View, savedInstanceState: Bundle?) {

    ITEMSList .add ( MainMarketTickClass("123"))
    ITEMSList .add ( MainMarketTickClass(" 123"))
    ITEMSList .add ( MainMarketTickClass("123"))

  var adapter = ContentAdapter (MainActivity(),ITEMSList)
    list.adapter = adapter
    list.layoutManager = LinearLayoutManager(this.context,LinearLayoutManager.VERTICAL,false)

}

override onItemClicked(item: MainMarketTickClass) {
// this method gets executed everytime an item gets clicked. You should 
// delegate the fragment transactions to the activity that hosts the fragment. 
// You should not do a fragment transaction from inside the fragment.
// You can use a similar interface approach to contact the activity from the Fragment.

}

kotlin-cant从RecyclerView适配器替换Fragment

1 个答案: