android - recyclerview适配器android中的数据绑定(bind)？

Question

我想将数据绑定(bind)到我的 recyclerview 适配器。这是我当前遵循 MVVM 模式的代码

fragment

class NotificationFragment : Fragment() {
var customeProgressDialog: CustomeProgressDialog? = null
private val appPreferences: AppPreference by inject()
private val notificationViewModel: NotificationViewModel by viewModel()
private lateinit var binding: FragmentNotificationBinding

override fun onCreateView(
    inflater: LayoutInflater, container: ViewGroup?,
    savedInstanceState: Bundle?
): View? {
    binding = FragmentNotificationBinding.inflate(inflater, container, false)
    return binding.getRoot()
}

override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
    super.onViewCreated(view, savedInstanceState)
    binding.notification.layoutManager=LinearLayoutManager(activity, LinearLayoutManager.VERTICAL, false)
    customeProgressDialog = CustomeProgressDialog(activity)
    notificationViewModel.notifications(
        appPreferences.getUsername(),
        appPreferences.getPassword(),
        appPreferences.getUserId()
    )
    initObservables()
}

private fun initObservables() {
    notificationViewModel.progressDialog?.observe(this, Observer {
        if (it!!) customeProgressDialog?.show() else customeProgressDialog?.dismiss()
    })
    notificationViewModel.apiResponse?.observe(
        viewLifecycleOwner,
        androidx.lifecycle.Observer { response ->
            if (response.dataList != null) {
                val notificationAdapter = NotificationAdapter(response.dataList as List<Data>)
                notificationAdapter.notifyDataSetChanged()
                binding.notification.adapter = notificationAdapter
            }
        })
}
}

查看模型

class NotificationViewModel(networkCall: NetworkCall) : ViewModel(),
Callback<ApiResponse> {
var progressDialog: SingleLiveEvent<Boolean>? = null
var apiResponse: MutableLiveData<ApiResponse>? = null
var networkCall: NetworkCall;

init {
    progressDialog = SingleLiveEvent<Boolean>()
    apiResponse = MutableLiveData<ApiResponse>()
    this.networkCall = networkCall
}

fun notifications(username: String?, password: String?, userId: String?) {
    progressDialog?.value = true
    val apiPost = ApiPost()
    apiPost.userName = username
    apiPost.password = password
    apiPost.UserId = userId
    apiPost.FileType = NetworkConstant.FILE_TYPE_NOT
    networkCall.getPDF(apiPost).enqueue(this)
}

override fun onFailure(call: Call<ApiResponse>, t: Throwable) {
    progressDialog?.value = false
}

override fun onResponse(call: Call<ApiResponse>, response: Response<ApiResponse>) {
    progressDialog?.value = false
    apiResponse?.value = response.body()
}
}

适配器

class NotificationAdapter(private val list: List<Data>) :
RecyclerView.Adapter<NotificationAdapter.ViewHolder>() {


override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
    val inflater = LayoutInflater.from(parent.context)
    val binding = ElementListBinding.inflate(inflater)

//val view = inflater.inflate(R.layout.element_list,parent,false) 返回ViewHolder(绑定(bind)) }

override fun onBindViewHolder(holder: ViewHolder, position: Int) {
    val movie: Data = list[position]
    holder.bind(movie)
    holder.itemView.setOnClickListener {

        if (!TextUtils.isEmpty(movie.filePath)) {
            try {
                val browserIntent = Intent(Intent.ACTION_VIEW, Uri.parse(movie.filePath))
                holder.itemView.context.startActivity(browserIntent)
            } catch (e: Exception) {
                e.printStackTrace()
            }
        }

    }
}

override fun getItemCount(): Int = list.size

inner class ViewHolder(binding: ElementListBinding) : RecyclerView.ViewHolder(binding.root) {
    fun bind(movie: Data) {
        binding.item = movie
    }
}
}


unable to find binding object

recyclerview元素列表xml

<layout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto">

<data>
    <variable
        name="data"
        type="com.mountmeru.model.Data" />
</data>

<androidx.cardview.widget.CardView
    android:id="@+id/main_cardview"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_marginBottom="5dp">

    <androidx.appcompat.widget.LinearLayoutCompat
        android:id="@+id/main_cardrl"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="horizontal">

        <RelativeLayout
            android:id="@+id/rl_newsdate"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:layout_weight="0.3">

            <androidx.appcompat.widget.AppCompatTextView
                android:id="@+id/tv_notifi"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginLeft="10dp"
                android:layout_marginTop="10dp"
                android:layout_marginRight="10dp"
                android:maxLines="2"
                android:text="@{data.displayName}"
                android:textColor="@android:color/black"
                android:textSize="16sp" />

            <androidx.appcompat.widget.AppCompatTextView
                android:id="@+id/tv_brief"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_below="@+id/tv_notifi"
                android:layout_marginLeft="10dp"
                android:layout_marginTop="5dp"
                android:layout_marginRight="10dp"
                android:textColor="@android:color/black"
                android:textSize="16sp"
                android:visibility="gone" />

            <androidx.appcompat.widget.AppCompatTextView
                android:id="@+id/tv_date"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_below="@+id/tv_brief"
                android:layout_marginLeft="10dp"
                android:layout_marginTop="2dp"
                android:layout_marginRight="10dp"
                android:maxLines="1"
                android:text="hey i am date"
                android:textColor="@color/inactive_text"
                android:textSize="14sp" />
        </RelativeLayout>

        <RelativeLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:layout_toRightOf="@+id/rl_newsdate"
            android:layout_weight="0.7"
            android:padding="5dp">

            <androidx.appcompat.widget.AppCompatImageView
                android:id="@+id/iv_notifi"
                android:layout_width="match_parent"
                android:layout_height="75dp"
                android:layout_centerHorizontal="true"
                android:layout_centerVertical="true"
                android:src="@drawable/mer" />

        </RelativeLayout>

    </androidx.appcompat.widget.LinearLayoutCompat>

</androidx.cardview.widget.CardView>
</layout>

有人可以确认我的 MVVM 实现是正确的还是需要一些重构？

如何在我的 recyclerview 列表元素 xml 中进行数据绑定(bind)？

Answer 1

您已经使用过<layout>作为 element_list.xml 中的父标记。现在您可以使用 DataBinding 在适配器类中对其进行扩充。请参阅下面的示例:

override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
    val binding = ElementListBinding.inflate(LayoutInflater.from(parent.context), parent, false)
    return ViewHolder(Binding)
}

您必须修改 ViewHolder 类，如下所示:

inner class ViewHolder(val binding: ElementListBinding) : RecyclerView.ViewHolder(binding.root) {
    fun bind(movie: Data) {
        with(itemView) {
            binding.tvNotifi.text = movie.displayName
            binding.tvDate.text = movie.UpdatedDate
            if (movie.description != null) {
                binding.tvBrief.text = movie.description
                binding.tvBrief.visibility = View.VISIBLE
            }
        }
    }
}