我是 Kotlin Android 开发的新手。在执行教程项目时,我需要将 ArrayAdapter
与自定义类一起使用。构建项目因错误而失败。
The MainActivity.kt class throwing the error:
class MainActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
setSupportActionBar(toolbar)
}
val dm = DataManager()
val adapterCourses = ArrayAdapter<CourseInfo>(
context = this,
android.R.layout.simple_spinner_item,
dm.courses.values.toList()
)
override fun onCreateOptionsMenu(menu: Menu): Boolean {
// Inflate the menu; this adds items to the action bar if it is present.
menuInflater.inflate(R.menu.menu_main, menu)
return true
}
override fun onOptionsItemSelected(item: MenuItem): Boolean {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
return when (item.itemId) {
R.id.action_settings -> true
else -> super.onOptionsItemSelected(item)
}
}
}
错误:
None of the following functions can be called with the arguments supplied:
public constructor ArrayAdapter<T : Any!>(@RecentlyNonNull p0: Context!, p1: Int) defined in android.widget.ArrayAdapter
public constructor ArrayAdapter<T : Any!>(@RecentlyNonNull p0: Context!, p1: Int, @RecentlyNonNull p2: Array<(out) CourseInfo!>!) defined in android.widget.ArrayAdapter
public constructor ArrayAdapter<T : Any!>(@RecentlyNonNull p0: Context!, p1: Int, p2: Int) defined in android.widget.ArrayAdapter
public constructor ArrayAdapter<T : Any!>(@RecentlyNonNull p0: Context!, p1: Int, p2: Int, @RecentlyNonNull p3: Array<(out) CourseInfo!>!) defined in android.widget.ArrayAdapter
public constructor ArrayAdapter<T : Any!>(@RecentlyNonNull p0: Context!, p1: Int, p2: Int, @RecentlyNonNull p3: (Mutable)List<CourseInfo!>!) defined in android.widget.ArrayAdapter
public constructor ArrayAdapter<T : Any!>(@RecentlyNonNull p0: Context!, p1: Int, @RecentlyNonNull p2: (Mutable)List<CourseInfo!>!) defined in android.widget.ArrayAdapter
CourseInfo 类:
class CourseInfo (val courseId: String, val title: String)
DataManager 类:
class DataManager {
val courses = HashMap<String, CourseInfo>()
val notes = ArrayList<NoteInfo>()
init {
initializeCourses()
}
private fun initializeCourses () {
var course = CourseInfo(courseId = "android_intent", title = "Android programming with intent.")
this.courses.set(course.courseId, course)
course = CourseInfo(courseId = "android_async", title = "Android Async Programming and Services.")
courses.set(course.courseId, course)
course = CourseInfo(courseId = "java_lang", title = "Java Fundamentals: The Java Language.")
courses.set(course.courseId, course)
course = CourseInfo(courseId = "java_core", title = "Java Fundamentals: The Core Platforms.")
courses.set(course.courseId, course)
}
}
最佳答案
也许为时已晚,但也许对某人有所帮助。如果您使用的是 fragment ,则不会通过已检查的答案来解决。您必须像这样调用 Activity 上下文。
val adapter = activity?.let {
ArrayAdapter<String>(
it,
android.R.layout.simple_spinner_item,
campaignsType
)
}
关于android - Kotlin ArrayAdapter 错误 : None of the following functions can be called with the arguments supplied,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/52948853/