Android Kotlin onItemSelectedListener for spinner无法正常工作

Question

我有一个带有一些项目（字符串）的微调器。我想将所选项目添加到列表中。我在网上读到我应该使用onItemSelectedListenerrather而不是onItemClickListener。

我实现了这个，但我不知道如何完成将其添加到列表中的步骤。

class NewKitListActivity : AppCompatActivity() {

var spinnerArray = arrayOf("Dumbell", "Punching Bag", "Yoga Ball", "Skipping Rope")
//var spinnerArray = arrayOf(DataService.kitList)



override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_new_kit_list)



    val spinner = newKitItemSpinner
    val spinnerArrayAdapter = ArrayAdapter<String>(this, android.R.layout.simple_spinner_dropdown_item, spinnerArray)
    //selected item will look like a spinner set from XML
    spinnerArrayAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item)
    spinner.adapter = spinnerArrayAdapter

    spinner.onItemSelectedListener = object : OnItemSelectedListener {
        override fun onItemSelected(parent: AdapterView<*>, view: View, position: Int, id: Long) {
            val selectedItem = parent.getItemAtPosition(position).toString()
            if (selectedItem == "Add new category") {
                // do your stuff
            }
        } // to close the onItemSelected

        override fun onNothingSelected(parent: AdapterView<*>) {

        }
    }}}

谢谢

Answer 1

（在Kotlin中）使用此代码：

yourSpinner?.onItemSelectedListener = object : AdapterView.OnItemSelectedListener{
        override fun onNothingSelected(parent: AdapterView<*>?) {

        }

        override fun onItemSelected(parent: AdapterView<*>?, view: View?, position: Int, id: Long) {

        }

    }

Answer 2

字符串将无法使用'=='进行检查，而是需要使用equals（“string”）

if (selectedItem.equals("Add new category")) {
            // do your stuff
        }

Answer 3

谢谢这对我有帮助，它的工作正常！ daysSpinner.onItemSelectedListener = object：AdapterView.OnItemSelectedListener {override fun onNothingSelected（parent：AdapterView <*>？）{

        }

        override fun onItemSelected(parent: AdapterView<*>?, view: View?, position: Int, id: Long) {

        }

    }

Answer 4

我是这样实现的。 1.创建空可变列表2.在微调器3上设置onItemSelectedListner。当用户选择项时将其添加到可变列表

查看我的答案以获取更多信息。它会帮助你：Android Koltin pass spinner values to mutable list