ScrollView and Spinner

问题

Spinner's "skeleton" shown behind another layout while scrolling up. When I scroll up Spinner's arrow and underline shown. I want it to hide it like it going to the behind of another layout.

before scrolling

after scrolling

I have a two ConstraintLayout second one for ScrollView.

Here is part of my XML.

<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="match_parent"
    android:layout_marginBottom="8dp"
    android:layout_marginLeft="8dp"
    android:layout_marginRight="8dp"
    android:layout_marginTop="8dp"
    app:layout_constraintBottom_toBottomOf="parent"
    app:layout_constraintLeft_toLeftOf="parent"
    app:layout_constraintRight_toRightOf="parent"
    app:layout_constraintTop_toTopOf="parent"
    tools:layout_editor_absoluteX="1dp"
    tools:layout_editor_absoluteY="159dp">




<TextView
    android:id="@+id/textView3"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_marginEnd="8dp"
    android:layout_marginLeft="8dp"
    android:layout_marginRight="8dp"
    android:layout_marginStart="8dp"
    android:layout_marginTop="7dp"
    android:text="Cummulative GPA: 0.00"
    app:layout_constraintLeft_toLeftOf="parent"
    app:layout_constraintRight_toRightOf="parent"
    app:layout_constraintTop_toBottomOf="@+id/textView2"/>

<ScrollView
    android:layout_width="0dp"
    android:layout_height="0dp"
    android:layout_marginTop="8dp"
    app:layout_constraintBottom_toBottomOf="parent"
    app:layout_constraintHorizontal_bias="1.0"
    app:layout_constraintLeft_toLeftOf="parent"
    app:layout_constraintRight_toRightOf="parent"
    app:layout_constraintTop_toBottomOf="@+id/textView3">

    <android.support.constraint.ConstraintLayout
        android:layout_width="match_parent"
        android:layout_height="0dp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintHorizontal_bias="1.0"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/textView3"
        app:layout_constraintVertical_bias="0.0">

        <TextView
            android:id="@+id/fenn1"
            style="@style/InputLabel"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="Fenn 1"
            app:layout_constraintBottom_toTopOf="@+id/spinner"
            app:layout_constraintLeft_toLeftOf="@+id/spinner"/>

        <Spinner
            android:id="@+id/spinner"
            style="@style/Widget.AppCompat.Spinner.Underlined"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginLeft="5dp"
            android:layout_marginStart="8dp"
            android:layout_marginTop="55dp"
            app:layout_constraintLeft_toLeftOf="parent"
            app:layout_constraintTop_toBottomOf="@+id/fenn1"
            />


        <TextView
            android:id="@+id/label1"
            style="@style/InputLabel"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="Fenn 2"
            app:layout_constraintBottom_toTopOf="@+id/spinner3"
            app:layout_constraintLeft_toLeftOf="@+id/spinner3"/>


        <Spinner
            android:id="@+id/spinner3"
            style="@style/Widget.AppCompat.Spinner.Underlined"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_marginLeft="8dp"
            android:layout_marginStart="8dp"
            android:layout_marginTop="43dp"
            app:layout_constraintLeft_toLeftOf="parent"
            app:layout_constraintTop_toBottomOf="@+id/spinner"/>

        <TextView
            android:id="@+id/label2"
            style="@style/InputLabel"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="Fenn 3"
            app:layout_constraintBottom_toTopOf="@+id/spinner6"
            app:layout_constraintLeft_toLeftOf="@+id/spinner6"/>

        <Spinner
            android:id="@+id/spinner6"
            style="@style/Widget.AppCompat.Spinner.Underlined"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginLeft="8dp"
            android:layout_marginStart="8dp"
            android:layout_marginTop="43dp"
            app:layout_constraintLeft_toLeftOf="parent"
            app:layout_constraintTop_toBottomOf="@+id/spinner3"/>

        <TextView
            android:id="@+id/label3"
            style="@style/InputLabel"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="Fenn 4"
            app:layout_constraintBottom_toTopOf="@+id/spinner7"
            app:layout_constraintLeft_toLeftOf="@+id/spinner7"/>

        <Spinner
            android:id="@+id/spinner7"
            style="@style/Widget.AppCompat.Spinner.Underlined"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginLeft="8dp"
            android:layout_marginStart="8dp"
            android:layout_marginTop="45dp"
            app:layout_constraintLeft_toLeftOf="parent"
            app:layout_constraintTop_toBottomOf="@+id/spinner6"/>

        <TextView
            android:id="@+id/label4"
            style="@style/InputLabel"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="Fenn 5"
            app:layout_constraintBottom_toTopOf="@+id/spinner8"
            app:layout_constraintLeft_toLeftOf="@+id/spinner8"
            />

        <Spinner
            android:id="@+id/spinner8"
            style="@style/Widget.AppCompat.Spinner.Underlined"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginLeft="8dp"
            android:layout_marginStart="8dp"
            android:layout_marginTop="43dp"
            app:layout_constraintLeft_toLeftOf="parent"
            app:layout_constraintTop_toBottomOf="@+id/spinner7"/>

        <TextView
            android:id="@+id/label5"
            style="@style/InputLabel"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="Fenn 6"
            app:layout_constraintBottom_toTopOf="@+id/spinner9"
            app:layout_constraintLeft_toLeftOf="@+id/spinner9"/>

        <Spinner
            android:id="@+id/spinner9"
            style="@style/Widget.AppCompat.Spinner.Underlined"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginLeft="8dp"
            android:layout_marginStart="8dp"
            android:layout_marginTop="40dp"
            app:layout_constraintLeft_toLeftOf="parent"
            app:layout_constraintTop_toBottomOf="@+id/spinner8"/>

        </android.support.constraint.ConstraintLayout>
    </ScrollView>
</android.support.constraint.ConstraintLayout>

回答1:

Try to set a background color for the ScrollView, like:

android:background="#00FFFFFF"

Please, do not ask me why it should work :) Just try it.

来源：https://stackoverflow.com/questions/45442578/scrollview-and-spinner