kotlinx.android.synthetic在DialogFragment中返回null

kotlinx.android.synthetic在DialogFragment中返回null,android,kotlin,android-databinding,Android,Kotlin,Android Databinding,在我开始之前,我读过类似的文章,如,但它们不适合我 正如我在标题中所解释的,当我点击肯定按钮(在本例中为“确定”)时,我会得到一个NPE。如果有人能指出我做错了什么,那就太好了!下面是我的设置的抽象版本 main.kt fragment_main.xml DialogFragment在onCreateDialog()之后调用onCreateView(),然后将该视图用于对话框的内容,替换在onCreateDialog()中已经设置的内容。因此,将视图创建移动到onCreateView(): cl

在我开始之前,我读过类似的文章,如,但它们不适合我

正如我在标题中所解释的,当我点击肯定按钮(在本例中为“确定”)时,我会得到一个NPE。如果有人能指出我做错了什么,那就太好了!下面是我的设置的抽象版本

main.kt fragment_main.xml
DialogFragment在
onCreateDialog()
之后调用
onCreateView()
,然后将该视图用于对话框的内容,替换在
onCreateDialog()中已经设置的内容。因此,将视图创建移动到
onCreateView()

class MainFragment: DialogFragment() {

    override fun onCreateDialog(savedInstanceState: Bundle?) =
            AlertDialog.Builder(context!!)
                .setView(FragmentMainBinding.inflate(LayoutInflater.from(context)).root)
                .setTitle(R.string.title_main)
                .setNegativeButton(R.string.cancel, null)
                .setPositiveButton(R.string.ok) { _, _ -> onPositiveButtonTapped() }
                .create()

    private fun onPositiveButtonTapped() {
        val g = arrayListOf(ground_nbr_edit_text.text.toString()) // NullPointerException
        // ...
    }

}
<?xml version="1.0" encoding="utf-8"?>
<layout>
    <LinearLayout
        xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical">

        <EditText
            android:id="@+id/ground_nbr_edit_text"
            android:layout_width="match_parent"
            android:layout_height="wrap_content" />

    </LinearLayout>
</layout>
class MainFragment: DialogFragment() {

    override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?) =
        FragmentMainBinding.inflate(inflater).root

    override fun onCreateDialog(savedInstanceState: Bundle?) =
            AlertDialog.Builder(context!!)
                .setTitle(R.string.title_main)
                .setNegativeButton(R.string.cancel, null)
                .setPositiveButton(R.string.ok) { _, _ -> onPositiveButtonTapped() }
                .create()

    private fun onPositiveButtonTapped() {
        val g = arrayListOf(ground_nbr_edit_text.text.toString()) // NullPointerException
        // ...
    }

}