Android:在列表中添加一个新项目,并使用Kotlin通过RecyclerView适配器显示它

android arraylist kotlin adapter startactivityforresult

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76 作者的声誉

我有一个包含RecyclerView的片段。当用户单击片段中的按钮(添加新项目)时,应用程序将用户(通过意图)带到表单以填充一些数据。

当我点击(添加项目)时,它应该将数据添加到数组列表并完成该屏幕。返回到片段后,应使用适配器将此数据添加到RecyclerView。

这是我的代码:

这是片段:

private val REQUEST_CODE = 2

internal lateinit var adapter: ShipmentItemAdapter

override fun onCreateView(inflater: LayoutInflater?, container: ViewGroup?, savedInstanceState: Bundle?): View? {

    return inflater!!.inflate(R.layout.fragment_step_three_shipment, container, false)
}

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

    btnAddNewShipmentStep3.setOnClickListener {
        val intent = Intent(context, AddItemActivity::class.java)
        startActivityForResult(intent, REQUEST_CODE)
    }
}

override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
    super.onActivityResult(requestCode, resultCode, data);

    val items = ArrayList<ItemsItem>()

    if (requestCode == REQUEST_CODE) {

        adapter = ShipmentItemAdapter(context, items)

        if (resultCode == Activity.RESULT_OK) {
            itemsShipments.visibility = View.VISIBLE
            itemsShipments.layoutManager = LinearLayoutManager(context)
            itemsShipments.setHasFixedSize(true)
            itemsShipments.adapter = adapter

        } else if (resultCode == Activity.RESULT_CANCELED) {
            itemsShipments.visibility = View.GONE
        }
    }
}

这是活动:

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

    linPackageAddShipment.setOnClickListener {
        edtPackageAddShipment.requestFocus()
    }

    linPiecesAddShipment.setOnClickListener {
        edtPiecesAddShipment.requestFocus()
    }

    linWeightAddShipment.setOnClickListener {
        edtWeightAddShipment.requestFocus()
    }

    linDescriptionAddShipment.setOnClickListener {
        edtDescriptionAddShipment.requestFocus()
    }


    btnAddItemAddShipment.setOnClickListener {
        val errors = collectData()

        collectData()

        if (errors.isEmpty()) {

            val intent = Intent()
            setResult(Activity.RESULT_OK, intent)
            finish()

        } else {
            val errorBody = errors.map { getString(it) }.joinToString("\n") { it }
            MaterialDialog.Builder(this)
                    .title("Oops")
                    .content(errorBody)
                    .positiveText(R.string.ok)
                    .positiveColor(ContextCompat.getColor(this, R.color.colorPrimary))
                    .onAny({ dialog, _ -> dialog.dismiss() })
                    .show()
        }
    }
  }

  private fun collectData(): ArrayList<Int> {
    val errors = ArrayList<Int>()
    val item = ItemsItem()

    if (edtPackageAddShipment.text.toString().isEmpty()) {
        errors.add(R.string.packages_must_not_be_empty)

    } else {
        item.numberOfPackages = edtPackageAddShipment.text.toString().toInt()
    }

    if (edtPiecesAddShipment.text.toString().isEmpty()) {
        errors.add(R.string.pieces_must_not_be_empty)

    } else {
        item.numberOfPieces = edtPiecesAddShipment.text.toString()
    }

    if (edtWeightAddShipment.text.toString().isEmpty()) {
        errors.add(R.string.weight_must_not_be_empty)

    } else {
        item.weightUnit = edtWeightAddShipment.text.toString().toInt()
    }

    if (edtHeightAddShipment.text.toString().isEmpty()) {
        errors.add(R.string.height_must_not_be_empty)

    } else {
        item.height = edtHeightAddShipment.text.toString()
    }

    if (edtWidthAddShipment.text.toString().isEmpty()) {
        errors.add(R.string.width_must_not_be_empty)

    } else {
        item.width = edtWidthAddShipment.text.toString()
    }
    if (edtLengthAddShipment.text.toString().isEmpty()) {
        errors.add(R.string.length_must_not_be_empty)

    } else {
        item.length = edtLengthAddShipment.text.toString()
    }

    if (edtDescriptionAddShipment.text.toString().isEmpty()) {
        errors.add(R.string.description_must_not_be_empty)

    } else {
        item.description = edtDescriptionAddShipment.text.toString()
    }

    CreateNewShipmentActivity.mainShipment.shipmentObj.items?.add(item)

    return errors
  }

  override fun onBackPressed() {
    setResult(Activity.RESULT_CANCELED)
    super.onBackPressed()
  }
}

这是适配器:

class ShipmentItemAdapter internal constructor(private val context: Context, private val items: List<ItemsItem>) : RecyclerView.Adapter<ShipmentItemAdapter.MyViewHolder>() {

  private val inflater: LayoutInflater = LayoutInflater.from(context)


  override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): MyViewHolder {
    val view = inflater.inflate(R.layout.item_shipment_package, parent, false)

    return MyViewHolder(view).listen { pos, type ->
        val item = items[pos]
        val intent = Intent(context, AddItemActivity::class.java)
        startActivity(context, intent, null)
    }
  }


  override fun onBindViewHolder(holder: MyViewHolder, position: Int) {
    holder.namePackageShipmentPackage.text = items[position].description
    holder.quantityPackageShipmentPackage.text = items[position].description
    holder.dimensionPackageHeightShipmentPackage.text = items[position].description
    holder.dimensionPackageWidthShipmentPackage.text = items[position].description
    holder.dimensionPackageLengthShipmentPackage.text = items[position].description

  }

  override fun getItemCount(): Int {
    return items.size
  }

  inner class MyViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {

    var namePackageShipmentPackage: AppCompatTextView = itemView.findViewById(R.id.namePackageShipmentPackage)
    var quantityPackageShipmentPackage: AppCompatTextView = itemView.findViewById(R.id.quantityPackageShipmentPackage)
    var dimensionPackageHeightShipmentPackage: AppCompatTextView = itemView.findViewById(R.id.dimensionPackageHeightShipmentPackage)
    var dimensionPackageWidthShipmentPackage: AppCompatTextView = itemView.findViewById(R.id.dimensionPackageWidthShipmentPackage)
    var dimensionPackageLengthShipmentPackage: AppCompatTextView = itemView.findViewById(R.id.dimensionPackageLengthShipmentPackage)


  }

  private fun <T : RecyclerView.ViewHolder> T.listen(event: (position: Int, type: Int) -> Unit): T {
    itemView.setOnClickListener {
        event.invoke(adapterPosition, itemViewType)
    }
    return this
  }

这些是对象模型:

class ShipmentObj {
    var items: ArrayList<ItemsItem?>? = null
}


data class ItemsItem(
    var numberOfPieces: String? = null,
    var length: String? = null,
    var description: String? = null,
    var numberOfPackages: Int? = null,
    var number: Int? = null,
    var width: String? = null,
    var height: String? = null,
    var weightUnit: Int? = null
)

当我尝试添加新项目时,片段中没有显示任何内容!我现在不在哪里犯错误?

谢谢。

作者: Abdulrahman 的来源 发布者: 2018 年 5 月 23 日

回应 1


0

96 作者的声誉

在onActivityResult中,您可以在代码中看到错误。您可以执行以下操作

val items = ArrayList<ItemsItem>()
adapter = ShipmentItemAdapter(context, items)

您为适配器分配了一个空的项目列表。如果我没错,你也不会传递你要发送的项目。

 if (errors.isEmpty()) {
        val intent = Intent()
        setResult(Activity.RESULT_OK, intent)
        finish()
 }

您完成活动而不传递任何项目。之前的活动没有收到任何内容。我无法执行您的代码,因为我没有执行它的所有元素。

作者: Antonio Altieri 发布者: 2018 年 5 月 23 日
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