將在 RecyclerView 中單擊的正確項目 position 返回到另一個活動

Question

我在這個問題上苦苦掙扎了好幾個星期，我總是從 RecyclerView 返回 (1)

• 我想返回正確的項目 position 單擊到 SceneFormeActivity 以便能夠選擇正確的 object，但我每次都得到相同的“1”所以相同的 Case1'Object 信息

我的主要 class.kt 代碼：

class ListeMeuble3DActivity : AppCompatActivity(),{
    var listMeubles = mutableListOf<Meuble>()

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_liste_meuble3_d)
         listMeubles = generateList()
        buildRecyclerView()
    }

    private fun generateList(): MutableList<Meuble>{

        val list = ArrayList<Meuble>()

           // to Add an Object Meuble(nom,prix,stock)

            val meuble = Meuble(R.drawable.fauteilgris, "Gris","25000da",1)
            val meuble1 = Meuble(R.drawable.fauteuille1, "","1000d&",1)
            val meuble2 = Meuble(R.drawable.burau, "Bureau","25000da",1)
            list.add(meuble)
            list.add(meuble1)
            list.add(meuble2)

        return list
    }

    fun buildRecyclerView() {
        mon_recycler.setHasFixedSize(true)
        //mon_recycler.setAdapter(mAdapter)
        mon_recycler.layoutManager = LinearLayoutManager(this)

        mon_recycler.adapter = MeubleAdapter(listMeubles.toTypedArray())
        {
            val intent3 = Intent(this, SceneformeActivity::class.java)
            intent3.putExtra("image_url",1)
            startActivity(intent3)
        }
     }
 }

我的適配器 Class.kt：

class MeubleAdapter(private val exampleList: Array<Meuble>,val listener: (Meuble)-> Unit) :
    RecyclerView.Adapter<MeubleAdapter.ExampleViewHolder>() {
    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ExampleViewHolder {
        val itemView = LayoutInflater.from(parent.context).inflate(R.layout.meuble_item,
            parent, false)
        return ExampleViewHolder(itemView)
    }
    override fun onBindViewHolder(holder: ExampleViewHolder, position: Int) {
        val currentItem = exampleList[position]
        holder.imageView.setImageResource(currentItem.imageResource)
        holder.textViewNomMeuble.text = currentItem.nom
        holder.textViewPrix.text = currentItem.prix
        holder.textViewStock.text = currentItem.stock.toString()

        holder.bind(exampleList[position],listener)
    }

    override fun getItemCount() = exampleList.size


    class ExampleViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {
        fun bind(meuble:Meuble,listener: (Meuble) -> Unit)= with(itemView)
        {
            android.util.Log.i("XXXX","FCT Bind ")
            setOnClickListener{(listener(meuble))}
        }

        val imageView: ImageView = itemView.image_view
        val textViewNomMeuble: TextView = itemView.nomMeuble
        val textViewStock: TextView = itemView.stock
        val textViewPrix: TextView = itemView.prix

    }
}

我在 SceneFormeActivity.java 中的 function 我應該得到項目 position

private void initializeGallery() {
        int imageUrl = getIntent().getIntExtra("image_url",0); // here, everytime it return 1
        LinearLayout gallery = findViewById(R.id.gallery_layout);
        int obj =imageUrl;
        switch (obj) {
            case 0: {
                ImageView andy = new ImageView(this);
                andy.setImageResource(R.drawable.fauteilgris);
                andy.setContentDescription("fauteuil Créme");
                andy.setOnClickListener(view ->{addObject(Uri.parse("foteuil.sfb"));});
                gallery.addView(andy);

            }
            break;
            case 1: {
                ImageView andy = new ImageView(this);
                andy.setImageResource(R.drawable.banc);
                andy.setContentDescription("banc extérieur");
                andy.setOnClickListener(view ->{addObject(Uri.parse("Bench.sfb"));});
                gallery.addView(andy);

            }
            break;
            case 2 : {
                ImageView andy = new ImageView(this);
                andy.setImageResource(R.drawable.burau);
                andy.setContentDescription("bureau");
                andy.setOnClickListener(view ->{addObject(Uri.parse("bureau.sfb"));});
                gallery.addView(andy);

            }
            break;
            case 3 : {
                ImageView andy = new ImageView(this);
                andy.setImageResource(R.drawable.fauteuille3);
                andy.setContentDescription("Fauteuil une place");
                andy.setOnClickListener(view ->{addObject(Uri.parse("ff.sfb"));});
                gallery.addView(andy);

            }
            break;
            default:Toast.makeText(getApplicationContext(),"Nothing",Toast.LENGTH_SHORT).show();

                break;

        }
    }

Answer 1

如果您真正想要的是該項目的 position，那么您根本不需要在點擊時發送 Meuble。 在您的適配器onBindViewHolder更改為：

override fun onBindViewHolder(holder: ExampleViewHolder, position: Int) {
        val currentItem = exampleList[position]
        holder.imageView.setImageResource(currentItem.imageResource)
        holder.textViewNomMeuble.text = currentItem.nom
        holder.textViewPrix.text = currentItem.prix
        holder.textViewStock.text = currentItem.stock.toString()

        holder.bind(position,listener)
    }

設置您的適配器現在應該如下所示：

 mon_recycler.adapter = MeubleAdapter(listMeubles.toTypedArray()){ position ->
            val intent3 = Intent(this, SceneformeActivity::class.java)
            intent3.putExtra("image_url", position)
            startActivity(intent3)
        }

---

編輯：擴展適配器的使用：

最初，您將兩件事傳遞給您的 Recyclerview 適配器 -

1. Meuble 列表（無需將其轉換為 TypedArray
2. lambda 將作用於單擊列表中的項目

考慮下面的重構代碼和我的內聯注釋。 注意 - 我不清楚你為什么要發送 position （假設只是為了測試？）所以我假設 object 中有一些你希望發送的 imageURL。 我將在下面展示您如何訪問它。

override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_liste_meuble3_d)
    listMeubles = generateList()
    buildRecyclerView()
}

private fun generateList(): MutableList<Meuble>{

    val list = mutableListOf<Meuble>()

       // to Add an Object Meuble(nom,prix,stock)

        val meuble = Meuble(R.drawable.fauteilgris, "Gris","25000da",1)
        val meuble1 = Meuble(R.drawable.fauteuille1, "","1000d&",1)
        val meuble2 = Meuble(R.drawable.burau, "Bureau","25000da",1)
        list.add(meuble)
        list.add(meuble1)
        list.add(meuble2)

    return list
}

fun buildRecyclerView() {
    mon_recycler.setHasFixedSize(true)
    mon_recycler.layoutManager = LinearLayoutManager(this)

    // NOTE: Here the lambda implicitly had an item of type Meuble passed.  We name it here but could have just used "it".
    mon_recycler.adapter = MeubleAdapter(listMeubles.toTypedArray())
    { item ->
        val intent3 = Intent(this, SceneformeActivity::class.java)
        intent3.putExtra("image_url",item.imageUrl)
        startActivity(intent3)
    }
 }

我的適配器 Class.kt：

// Don't need to pass as a TypedArray - List is fine
class MeubleAdapter(private val exampleList: List<Meuble>,val listener: (Meuble)-> Unit) :
    RecyclerView.Adapter<MeubleAdapter.ExampleViewHolder>() {
    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ExampleViewHolder {
        val itemView = LayoutInflater.from(parent.context).inflate(R.layout.meuble_item,
            parent, false)
        return ExampleViewHolder(itemView)
    }
    override fun onBindViewHolder(holder: ExampleViewHolder, position: Int) {
        val currentItem = exampleList[position]
        holder.imageView.setImageResource(currentItem.imageResource)
        holder.textViewNomMeuble.text = currentItem.nom
        holder.textViewPrix.text = currentItem.prix
        holder.textViewStock.text = currentItem.stock.toString()

        holder.bind(exampleList[position],listener)
    }

    override fun getItemCount() = exampleList.size


    class ExampleViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {
        fun bind(meuble:Meuble,listener: (Meuble) -> Unit)= with(itemView)
        {
            android.util.Log.i("XXXX","FCT Bind ")
            setOnClickListener{(listener(meuble))}
        }

        val imageView: ImageView = itemView.image_view
        val textViewNomMeuble: TextView = itemView.nomMeuble
        val textViewStock: TextView = itemView.stock
        val textViewPrix: TextView = itemView.prix

    }
}

Answer 2

所以我使用了這個解決方案，我將點擊的 object 的名稱（標稱）傳遞給 SceneFormActivity 以獲取參考並在下一個活動中顯示我的 3D object：

主要代碼

   val intent3 = Intent(this, SceneformeActivity::class.java)
            intent3.putExtra("image_url",it.nom) //  it.nom to get the name of the object clicked
            startActivity(intent3)

在 SceneformeActivity 中：

 private void initializeGallery() {
        String imageUrl = getIntent().getStringExtra("image_url"); // changed this from getInt to getString to get the name
        LinearLayout gallery = findViewById(R.id.gallery_layout);
        String obj =imageUrl;   
        switch (obj) {
            case "fauteilgris": { // case "String": the name of the object clicked in the previous activity(RecyclerView)
                ImageView andy = new ImageView(this);
                andy.setImageResource(R.drawable.fauteilgris);
                andy.setContentDescription("fauteuil Créme");
                andy.setOnClickListener(view ->{addObject(Uri.parse("foteuil.sfb"));});
                gallery.addView(andy);

            }
            break;
            case "banc": {
                ImageView andy = new ImageView(this);
                andy.setImageResource(R.drawable.banc);
                andy.setContentDescription("banc extérieur");
                andy.setOnClickListener(view ->{addObject(Uri.parse("Bench.sfb"));});
                gallery.addView(andy);

            }
            break;
            case "burau": {
                ImageView andy = new ImageView(this);
                andy.setImageResource(R.drawable.burau);
                andy.setContentDescription("bureau");
                andy.setOnClickListener(view ->{addObject(Uri.parse("bureau.sfb"));});
                gallery.addView(andy);

            }
            break;
 default:Toast.makeText(getApplicationContext(),"No Object",Toast.LENGTH_SHORT).show();

                break;

        }
    }