I have this layout :
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#ffffff"
android:clickable="true"
android:focusable="true">
<android.support.constraint.ConstraintLayout
android:id="@+id/details"
android:layout_width="500dp"
android:layout_height="wrap_content"
android:layout_marginStart="8dp"
android:layout_marginTop="8dp"
android:layout_marginEnd="8dp"
android:layout_marginBottom="32dp"
android:background="@color/grayEB"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toStartOf="@+id/shutdownButton"
app:layout_constraintHorizontal_bias="0.0"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintVertical_bias="0.007">
<TextView
android:id="@+id/textView2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="8dp"
android:layout_marginTop="8dp"
android:text="Flusso autorizzativo"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<TextView
android:id="@+id/textView3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="8dp"
android:layout_marginTop="8dp"
android:text="--"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/textView2" />
<TextView
android:id="@+id/textView4"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="8dp"
android:layout_marginEnd="8dp"
android:text="Totale cliente"
app:layout_constraintBaseline_toBaselineOf="@+id/textView2"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.274"
app:layout_constraintStart_toEndOf="@+id/textView2" />
<TextView
android:id="@+id/textView5"
android:layout_width="wrap_content"
android:layout_height="15dp"
android:layout_marginStart="8dp"
android:layout_marginTop="12dp"
android:layout_marginEnd="8dp"
android:layout_marginBottom="8dp"
android:text="Spesa PRE: € --"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toStartOf="@+id/textView6"
app:layout_constraintHorizontal_bias="0.959"
app:layout_constraintStart_toEndOf="@+id/textView3"
app:layout_constraintTop_toBottomOf="@+id/textView4"
app:layout_constraintVertical_bias="0.0" />
<TextView
android:id="@+id/textView6"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginEnd="60dp"
android:text="Spesa stimata: € --"
app:layout_constraintBaseline_toBaselineOf="@+id/textView5"
app:layout_constraintEnd_toEndOf="parent" />
</android.support.constraint.ConstraintLayout>
<Button
android:id="@+id/shutdownButton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="16dp"
android:layout_marginEnd="8dp"
android:text="ShutDown !!!"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<android.support.v4.view.ViewPager
android:id="@+id/frameLayout2"
android:layout_width="0dp"
android:layout_height="0dp"
android:layout_marginStart="8dp"
android:layout_marginEnd="8dp"
android:layout_marginBottom="8dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/MyTabs">
</android.support.v4.view.ViewPager>
<android.support.design.widget.TabLayout
android:id="@+id/MyTabs"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginStart="8dp"
android:layout_marginEnd="8dp"
android:padding="0dp"
android:elevation="4dp"
android:paddingBottom="4dp"
app:tabGravity="center"
app:tabMode="scrollable"
app:layout_constraintBottom_toTopOf="@+id/frameLayout2"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/details"
app:layout_constraintVertical_chainStyle="packed"
android:background="#ffff"/>
</android.support.constraint.ConstraintLayout>
I have set the elevation and paddingBottom of MyTabs to show the shadow under the tablayout, but in this way the shadown is showed not only on the bottom side but on each side.
I have to show the shadow only on the bottom side, what I have to do ?
OT : this layout is also too slow to be rendered