无法让SupportMapFragment返回任何内容。似乎始终为null

Question

所以这是我的代码：Krux的事情是onMapReady没有被调用所以我玩了

错误

进程：com.example.herbstzu.listview，PID：16963 kotlin.TypeCastException：null无法转换为非null类型com.google.android.gms.maps.SupportMapFragment

XML

.....
 <LinearLayout
            android:id="@+id/LayoutInfo"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:layout_marginVertical="10dp"
            android:orientation="horizontal">

            <ImageView
                android:id="@+id/imagePhone2"
                android:layout_width="60dp"
                android:layout_height="60dp"
                android:layout_gravity="start"
                android:layout_marginLeft="15dp"
                android:layout_marginRight="15dp"
                app:srcCompat="@drawable/ic_exclamation" />

            <TextView
                android:id="@+id/info_text"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:text="TextView"
                android:textColor="#000000" />
        </LinearLayout>

        <fragment
            class="com.google.android.gms.maps.MapFragment"
            android:id="@+id/mapF"
            android:layout_width="match_parent"
            android:layout_height="200dp"/>

    </LinearLayout>

</ScrollView>

Kotlin片段类

import android.os.Bundle
import android.support.v4.app.Fragment
import android.util.Log
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import com.google.android.gms.maps.model.LatLng
import com.google.android.gms.maps.model.MarkerOptions
import com.google.android.gms.maps.SupportMapFragment
import com.google.android.gms.maps.CameraUpdateFactory
import com.google.android.gms.maps.GoogleMap
import com.google.android.gms.maps.OnMapReadyCallback

class Event_details : Fragment(),OnMapReadyCallback{

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
    }

    override fun onCreateView(inflater: LayoutInflater?, container: ViewGroup?,
                              savedInstanceState: Bundle?): View? {
        var myView = inflater!!.inflate(R.layout.fragment_event_details, container, false)

        var mapFragment = activity.fragmentManager.findFragmentById(R.id.mapF) as SupportMapFragment
        mapFragment.getMapAsync(this)

        return  myView
    }
     override fun onMapReady(googleMap: GoogleMap) {
        Log.d("onMapready","MapReady")
        val cphbusiness = LatLng(55.770535, 12.511922)
        googleMap.addMarker(MarkerOptions().position(cphbusiness).title("Her"))
        googleMap.moveCamera(CameraUpdateFactory.zoomTo(16.0F))
        googleMap.moveCamera(CameraUpdateFactory.newLatLng(cphbusiness))

    }
}// Required empty public constructor

Answer 1

您正在使用错误的片段管理器。您需要使用supportFragmentManager

    var mapFragment = activity.supportFragmentManager.findFragmentById(R.id.mapF) as SupportMapFragment