Передача экземпляра объекта между двумя действиями в Котлине
Мне интересно, может ли кто-нибудь помочь мне исправить эту ошибку с помощью Intent?
У меня есть 2 действия для подключения: первое действие для вида сетки "MainActivity.kt", второе для представления списка "Main2Activity.kt", и у меня есть 2 экземпляра объекта (adapter1,adapter2) из "Main2Activity.kt", и я хочу передать конкретный экземпляр объекта (адаптер1) или (адаптер2) при нажатии на конкретное изображение в "MainActivity.kt"
Примечание: я использую BaseAdapter
Вот 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 {
if (foodView.ivFoodImage.context!!.equals(a) ) {
val intent = Intent(context, Main2Activity::class.java)
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)
}
else if (foodView.ivFoodImage.context!!.equals(b)) {
val intent = Intent(context, Main2Activity::class.java)
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
}
}
}
Вот Main2Activity.kt
class Main2Activity : AppCompatActivity() {
companion object {
val EXTRA_ADAPTER_MODE = "extra_adapter_mode"
}
var adapter1: FoodAdapter? = null
var adapter2: FoodAdapter2? = null
var listOfFoods2 = ArrayList<Food>()
var listOfFoods3 = ArrayList<Food>()
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main2)
val bundle = intent?.getIntExtra(EXTRA_ADAPTER_MODE, AdapterType.ADAPTER_TYPE_1.ordinal)
val name = bundle?.let { AdapterType.fromOrdinal(it) }
val des = bundle?.let { AdapterType.fromOrdinal(it) }
val image = bundle?.let { AdapterType.fromOrdinal(it) }
//val bundle = intent.extras
//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))
//listOfFoods2.add(Food("Coffee"," Coffee preparation is",R.drawable.c))
//listOfFoods2.add(Food("Coffee"," Coffee preparation is",R.drawable.d))
// load foods3
//listOfFoods3.add(Food("Coffee"," Coffee preparation is",R.drawable.a))
//listOfFoods3.add(Food("Coffee"," Coffee preparation is",R.drawable.b))
listOfFoods3.add(Food("Coffee", " Coffee3 preparation is", R.drawable.c))
listOfFoods3.add(Food("Coffee", " Coffee4 preparation is", R.drawable.d))
if(adapter1 ==lvFoods2.adapter) {
adapter1 = FoodAdapter(listOfFoods2, this)
lvFoods2.adapter = adapter1
} else if (adapter2==lvFoods2.adapter) {
adapter2 = FoodAdapter2(listOfFoods3, this)
lvFoods2.adapter = adapter2
}
}
class FoodAdapter : 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, p1: View?, p2: ViewGroup?): View {
val food = this.listOfFoodsLocal2[p0]
var inflator = context!!.getSystemService(Context.LAYOUT_INFLATER_SERVICE) as LayoutInflater
val foodView = inflator.inflate(R.layout.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(R.layout.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
}
}
}
Вот перечислимый класс
enum class AdapterType {
ADAPTER_TYPE_1,
ADAPTER_TYPE_2,
ADAPTER_TYPE_3;
companion object {
fun fromOrdinal(name:String,des:String,image: Int): AdapterType? {
return AdapterType.values().firstOrNull { it.ordinal == image}
}
}
}
2 ответа
Создайте IntDef как:
@Retention(SOURCE)
@IntDef({ADAPTER_MODE_1, ADAPTER_MODE_2, ADAPTER_MODE_3})
public @interface AdapterMode {}
public static final int ADAPTER_MODE_1 = 0;
public static final int ADAPTER_MODE_2 = 1;
public static final int ADAPTER_MODE_3 = 2;
//...
и добавьте int в связку. Для Kotlin вы должны использовать объект-компаньон для определения таких переменных, как
class FirstActivity {
companion object {
val ADAPTER_MODE1 = 0
val ADAPTER_MODE2 = 1
val ADAPTER_MODE3 = 2
//...
}
}
Таким образом, вы можете передать неограниченное количество адаптеров для вашего второго занятия
РЕДАКТИРОВАТЬ: Kotlin не поддерживает @IntDef, поэтому вы должны использовать перечисление для этого:
enum class AdapterType {
ADAPTER_TYPE_1,
ADAPTER_TYPE_2,
ADAPTER_TYPE_3;
companion object {
fun fromOrdinal(ordinal: Int): AdapterType? {
return AdapterType.values().firstOrNull { it.ordinal == ordinal }
}
}
}
Тогда используйте это как:
class FirstActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
val intent = Intent(this, SecondActivity::class.java)
intent.putExtra(SecondActivity.EXTRA_ADAPTER_MODE, AdapterType.ADAPTER_TYPE_2.ordinal)
}
}
И получить это как:
class SecondActivity : AppCompatActivity() {
companion object {
val EXTRA_ADAPTER_MODE = "extra_adapter_mode"
}
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
//...
val adapterTypeOrdinal = intent?.getIntExtra(EXTRA_ADAPTER_MODE, AdapterType.ADAPTER_TYPE_1.ordinal)
val adapterType = adapterTypeOrdinal?.let { AdapterType.fromOrdinal(it) }
// do something with it
}
}
Вы не можете передавать адаптеры между действиями. По крайней мере, чистым способом, рекомендованным Google. Адаптеры не реализуют интерфейс Parcelable или Serializable. Общее правило, как указал Nino Handler, - использовать Intent для отправки данных (не самих адаптеров), которые следует использовать для создания Adapter.