kotlinでの表現が期待通りに動作しない場合

Question

誰かが私がこの問題を解決するのを助けることができるかどうか疑問ですWhen Expression特定のコードブロック？

私は間を接続する2つの活動持っている：私はのでMain2Activity class 内のコードの特定のブロックとすると、式を適用するための問題を得た第二の活動では、最初の活動はMainActivity.ktであり、第二の活動がMain2Activity.ktある

をたくはMain2Activity classときADAPTER_TYPE_2を渡すようMainActivity classでは画像をクリックしてください最初のアクティビティクラスで画像bをクリックすると、それは常にMain2Activity class

内のコードの最初のブロックを適用していることの主な問題は内部で特定のアダプタを渡します

注：最初のアクティビティはGridViewを使用し、第2の活性はListViewを使用し、第2の活性ここ

の各アダプタから成るiはMain2Activity.kt内部2つのアダプターを有し、iはenumを使用していMainActivity.kt

class MainActivity : AppCompatActivity() { 

var adapter:FoodAdapter?=null 
var listOfFoods =ArrayList<Food>() 
override fun onCreate(savedInstanceState: Bundle?) { 
super.onCreate(savedInstanceState) 
setContentView(layout.activity_main) 


// load foods 
listOfFoods.add(Food("Coffee"," Coffee preparation is", a)) 
listOfFoods.add(Food("Coffee"," Coffee preparation is", b)) 
listOfFoods.add(Food("Coffee"," Coffee preparation is", c)) 
listOfFoods.add(Food("Coffee"," Coffee preparation is", d)) 

adapter= FoodAdapter(this,listOfFoods) 

gvListFood.adapter =adapter 

} 


class FoodAdapter: BaseAdapter { 
var listOfFood= ArrayList<Food>() 
var context: Context?=null 
constructor(context:Context,listOfFood:ArrayList<Food>):super(){ 
    this.context=context 
    this.listOfFood=listOfFood 
} 
override fun getView(p0: Int, p1: View?, p2: ViewGroup?): View? { 
    val food = this.listOfFood[p0] 
    var inflator = context!!.getSystemService(Context.LAYOUT_INFLATER_SERVICE) as LayoutInflater 
    var foodView= inflator.inflate(layout.food_ticket,null) 
    foodView.ivFoodImage.setImageResource(food.image!!) 
    foodView.ivFoodImage.setOnClickListener { 


     val intent = Intent(context, Main2Activity::class.java) 

     when (foodView) { 
      foodView.ivFoodImage.also { a } -> 
       intent.putExtra(Main2Activity.EXTRA_ADAPTER_MODE, AdapterType.ADAPTER_TYPE_1.ordinal) { 

        intent.putExtra("name", food.name!!) 
        intent.putExtra("des", food.des!!) 
        intent.putExtra("image", food.image!!) 
        context!!.startActivity(intent) 
       } 

      foodView.ivFoodImage.also { b } -> 
       intent.putExtra(Main2Activity.EXTRA_ADAPTER_MODE, AdapterType.ADAPTER_TYPE_2.ordinal) { 

        intent.putExtra("name", food.name!!) 
        intent.putExtra("des", food.des!!) 
        intent.putExtra("image", food.image!!) 
        context!!.startActivity(intent) 
      } 
     } 

    } 
    return foodView 
} 

override fun getItem(p0: Int): Any { 
    return listOfFood[p0] 
} 

override fun getItemId(p0: Int): Long { 
    return p0.toLong() 
} 

override fun getCount(): Int { 

    return listOfFood.size 
} 

} 
} 

ありますここで

最初の活動のためのfood_ticket.xmlは

<?xml version="1.0" encoding="utf-8"?> 
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
xmlns:app="http://schemas.android.com/apk/res-auto" 
android:layout_width="63pt" 
android:layout_height="wrap_content" 
android:background="@color/gray" 
android:orientation="vertical" 
android:padding="3pt"> 

<LinearLayout 
android:gravity="center" 
android:layout_width="match_parent" 
android:layout_height="match_parent" 
android:background="@drawable/background" 
android:orientation="vertical"> 

<ImageView 
    android:id="@+id/ivFoodImage" 
    android:layout_width="50pt" 
    android:layout_height="50pt" 
    app:srcCompat="@drawable/c" /> 

<TextView 
    android:id="@+id/tvName" 
    android:layout_width="match_parent" 
    android:layout_height="wrap_content" 
    android:gravity="center" 
    android:text="Coffe" 
    android:textSize="20sp" /> 
</LinearLayout> 
</LinearLayout> 

ですここで210

2活性についてactivity_main2.xml

<?xml version="1.0" encoding="utf-8"?> 
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
xmlns:tools="http://schemas.android.com/tools" 
android:layout_width="match_parent" 
android:layout_height="match_parent" 
android:background="@color/gray" 
android:orientation="vertical" 
tools:context="com.marzadmz.startup.Main2Activity"> 

<ListView 
android:id="@+id/lvFoods2" 
android:layout_width="match_parent" 
android:layout_height="match_parent" 
android:background="@color/gray" /> 
</LinearLayout> 

列挙クラス

enum class AdapterType { 
ADAPTER_TYPE_1, 
ADAPTER_TYPE_2; 



    companion object { 
     fun fromOrdinal(ordinal: Int): AdapterType? { 
      return AdapterType.values().firstOrNull { it.ordinal == ordinal } 
     } 
    } 
} 

null error imageためAdapterType.kt Main2Activity.kt

class Main2Activity : AppCompatActivity() { 
companion object { 
    val EXTRA_ADAPTER_MODE = "extra_adapter_mode" 

} 

    var adapter1: FoodAdapter1?= null 
    var adapter2: FoodAdapter2? = null 
    var listOfFoods2 = ArrayList<Food>() 
    var listOfFoods3 = ArrayList<Food>() 
override fun onCreate(savedInstanceState: Bundle?) { 
    super.onCreate(savedInstanceState) 
    setContentView(activity_main2) 


    val bundle = intent.extras 
    val adapterTypeOrdinal = intent.getIntExtra(EXTRA_ADAPTER_MODE, 0) // 0 is the default value 
    val type = AdapterType.fromOrdinal(ordinal = adapterTypeOrdinal) 


    val name = bundle.getString("name") 
    val des = bundle.getString("des") 
    val image = bundle.getInt("image") 



    ivFoodImage2?.let { 
     it.setImageResource(image) 
    } 

    tvName2?.let { 
     it.text = name 
    } 

    tvDes2?.let { 
     it.text = des 
    } 


    // load foods2 
    listOfFoods2.add(Food("Coffee", " Coffee1 preparation is", R.drawable.a)) 
    listOfFoods2.add(Food("Coffee", " Coffee2 preparation is", R.drawable.b)) 



    // load foods3 
    listOfFoods3.add(Food("Coffee", " Coffee3 preparation is", R.drawable.c)) 
    listOfFoods3.add(Food("Coffee", " Coffee4 preparation is", R.drawable.d)) 

    //var ADAPTER_TYPE_1 = adapter1 
    //var ADAPTER_TYPE_2 = adapter2 

    lvFoods2.adapter = when (type) { 
     AdapterType.ADAPTER_TYPE_1-> FoodAdapter1(listOfFoods2, this) 
     AdapterType.ADAPTER_TYPE_2-> FoodAdapter2(listOfFoods3, this) 
     else -> lvFoods2.adapter 
    } 
} 



class FoodAdapter1 : BaseAdapter{ 
    var context: Context? = null 
    var listOfFoodsLocal2 = ArrayList<Food>() 

    constructor(listOfFoods2: ArrayList<Food>, context: Context) : super() { 
     this.listOfFoodsLocal2 = listOfFoods2 
     this.context = context 
    } 

    override fun getView(p0: Int, foodView: View?, p2: ViewGroup?): View { 
     val food = this.listOfFoodsLocal2[p0] 
     var inflator = context!!.getSystemService(Context.LAYOUT_INFLATER_SERVICE) as LayoutInflater 
     val foodView = inflator.inflate(food_ticket2, null) 



     foodView.ivFoodImage2?.let { 
      it.setImageResource(food.image!!) 
       } 
     foodView.tvName2?.let { 

      it.text = food.name!! 
     } 
     foodView.tvDes2?.let { 
      it.text = food.des!! 
     } 

     foodView.ivFoodImage2.setOnClickListener { 

      //move to next 
      val intent = Intent(context, FoodDetails::class.java) 
      intent.putExtra("name", food.name!!) 
      intent.putExtra("des", food.des!!) 
      intent.putExtra("image", food.image!!) 

      context!!.startActivity(intent) 

     } 
     return foodView 

    } 


    override fun getItem(p0: Int): Any { 
     return listOfFoodsLocal2[p0] 
    } 

    override fun getItemId(p0: Int): Long { 
     return p0.toLong() 
    } 

    override fun getCount(): Int { 
     return listOfFoodsLocal2.size 
    } 

} 

class FoodAdapter2 : BaseAdapter { 
    var context: Context? = null 
    var listOfFoodsLocal3 = ArrayList<Food>() 

    constructor(listOfFoods3: ArrayList<Food>, context: Context) : super() { 
     this.listOfFoodsLocal3 = listOfFoods3 
     this.context = context 
    } 

    override fun getView(p0: Int, p1: View?, p2: ViewGroup?): View { 
     val food = this.listOfFoodsLocal3[p0] 
     var inflator = context!!.getSystemService(Context.LAYOUT_INFLATER_SERVICE) as LayoutInflater 
     val foodView = inflator.inflate(food_ticket2, null) 


      foodView.ivFoodImage2?.let { 
       it.setImageResource(food.image!!) 
      } 
      foodView.tvName2?.let { 
       it.text = food.name!! 
      } 
      foodView.tvDes2?.let { 
       it.text = food.des!! 
      } 




     foodView.ivFoodImage2.setOnClickListener { 

      //move to next 
      val intent = Intent(context, FoodDetails::class.java) 
      intent.putExtra("name", food.name!!) 
      intent.putExtra("des", food.des!!) 
      intent.putExtra("image", food.image!!) 

      context!!.startActivity(intent) 

     } 
     return foodView 

    } 


    override fun getItem(p0: Int): Any { 
     return listOfFoodsLocal3[p0] 
    } 

    override fun getItemId(p0: Int): Long { 
     return p0.toLong() 
    } 

    override fun getCount(): Int { 
     return listOfFoodsLocal3.size 
    } 

} 
} 

あります2nd picture

Answer 1

実装がオフ

var ADAPTER_TYPE_1 = adapter1 
var ADAPTER_TYPE_2 = adapter2 

lvFoods2.adapter = when (lvFoods2.adapter) { 
    ADAPTER_TYPE_1 -> FoodAdapter1(listOfFoods2, this).also { ADAPTER_TYPE_1 = it } 
    ADAPTER_TYPE_2 -> FoodAdapter2(listOfFoods3, this).also { ADAPTER_TYPE_2 = it } 
    else -> lvFoods2.adapter 
} 

adapter1変数がヌルならびにlvFoods2.adapterです。私はあなたのコードを理解する方法から、それは次のようになります。？？

lvFoods2.adapter = when (type) { 
    ADAPTER_TYPE_1 -> FoodAdapter1(listOfFoods2, this) 
    ADAPTER_TYPE_2 -> FoodAdapter2(listOfFoods3, this) 
    else -> lvFoods2.adapter 
}