Question

我尝试将List[Ccountry]从一个活动发送到另一个活动，其中Ccountry是一个可以列举的案例类。所有代码都是用Scala编写的。问题是我在行ClassCastException中发送列表时收到intent.putExtra("foo", list.asInstanceOf[Parcelable])。谁能告诉我这里的问题是什么？

Logcat错误

FATAL EXCEPTION: main

Process: com.sam.scalasample, PID: 15003

java.lang.ClassCastException: scala.collection.immutable.$colon$colon cannot be cast to android.os.Parcelable
        at com.sam.scalasample.MainActivity$$anon$11.onClick(MainActivity.scala:173)

参与第二项活动

val bundle: Bundle = getIntent.getExtras
var foo: List[Ccountry] = List()
if (bundle != null) {
    foo =  bundle.getParcelable("foo").asInstanceOf[List[Ccountry]]
}

发送数据

sendArrayList.setOnClickListener(new OnClickListener {
        override def onClick(v: View): Unit = {
            var intent: Intent = new Intent(MainActivity.this, classOf[ParcelActivity])
            var list: List[Ccountry] = List()
            var listBuffer: ListBuffer[Ccountry] = new ListBuffer[Ccountry]()

            listBuffer += Ccountry("AF", "Afghanistan")
            listBuffer += Ccountry("AL", "Albania")
            listBuffer += Ccountry("DZ", "Algeria")
            list = listBuffer.toList
            intent.putExtra("foo", list.asInstanceOf[Parcelable])
            intent.putExtra(Parse.KEY, Parse.ARRAYLIST)
            startActivity(intent)
        }
})

Answer 1

我在发送arraylist的类中导入了“scala.collection.JavaConversions._”。

//Getting it

if(getIntent!=null){
       if(getIntent.getExtras.getString(Parse.KEY).equals(Parse.ARRAYLIST)){
        val bundle: Bundle = getIntent.getExtras
        var array = new util.ArrayList[Ccountry]()
        if (bundle != null) {
          array = bundle.getParcelableArrayList("foo")
          println("sammy_array_size: "+array.size())
        }




      }

//Sending it

sendArrayList.setOnClickListener(new OnClickListener {
      override def onClick(v: View): Unit = {
        var intent: Intent = new Intent(MainActivity.this, classOf[ParcelActivity])
        var list: List[Ccountry] = List()
        var listBuffer: ListBuffer[Ccountry] = new ListBuffer[Ccountry]()

        listBuffer += Ccountry("AF", "Afghanistan")
        listBuffer += Ccountry("AL", "Albania")
        listBuffer += Ccountry("DZ", "Algeria")
        list = listBuffer.toList
        val array = new util.ArrayList(list)
        val bundle: Bundle = new Bundle
        bundle.putParcelableArrayList("foo", array)
        intent.putExtras(bundle)
        intent.putExtra(Parse.KEY, Parse.ARRAYLIST)
        startActivity(intent)
      }
    })

android scala通过意图发送List

1 个答案: