微调器自定义下拉视图怪异行为

在微调器中,我放置了以下自定义下拉视图

<android.support.constraint.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="wrap_content">

<ImageView
    android:id="@+id/imageView_allowance"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_marginBottom="8dp"
    android:layout_marginStart="16dp"
    android:layout_marginTop="8dp"
    android:visibility="gone"
    app:layout_constraintBottom_toBottomOf="@+id/tv_allowance"
    app:layout_constraintStart_toStartOf="parent"
    app:layout_constraintTop_toTopOf="@+id/tv_allowance"
    app:srcCompat="@drawable/ic_local_dining_black_24dp" />

<TextView
    android:id="@+id/tv_allowance"
    android:layout_width="0dp"
    android:layout_height="wrap_content"
    android:layout_marginBottom="16dp"
    android:layout_marginEnd="8dp"
    android:layout_marginStart="16dp"
    android:layout_marginTop="16dp"
    android:text="TextView"
    app:layout_constraintBottom_toBottomOf="parent"
    app:layout_constraintEnd_toEndOf="parent"
    app:layout_constraintStart_toEndOf="@+id/imageView_allowance"
    app:layout_constraintTop_toTopOf="parent"
    tools:text="Repas du midi" />

并制作了如下自定义适配器:

class SpinnerAllowanceAdapter extends ArrayAdapter<String> {

    SpinnerAllowanceAdapter(@NonNull Context context, int resource, int textViewResourceId, @NonNull String[] objects) {
        super(context, resource, textViewResourceId, objects);
    }

    @Override
    public boolean isEnabled(int position) {
        return position != 0;
    }

    @Override
    public View getDropDownView(int position, View convertView, ViewGroup parent) {
        View view = super.getDropDownView(position, convertView, parent);

        TextView tv = view.findViewById(R.id.tv_allowance);
        ImageView iv = view.findViewById(R.id.imageView_allowance);

        if (position == 0) {
            // Set the hint text color gray
            tv.setTextColor(Color.GRAY);
        } else {
            iv.setVisibility(View.VISIBLE);
            tv.setTextColor(Color.BLACK);
            iv.setImageResource(getAllowanceIcon(position));
        }
        return view;
    }



    private int getAllowanceIcon(int position){
        int drawableId;

        //image selection

        return drawableId;
    }
}

当没有选择任何项目时,它会正常工作。但当用户从微调器中选择一个项目时,该项目的图像视图将消失在下拉视图中。

drop down view when no items have been selected by the user

Drop down view, image dispared on item selected

始终激活图像视图是我的代码中的正常行为还是缺少部分?

非常感谢。