Signal-Android/app/src/main/res/layout/fragment_registration_lock.xml

<?xml version="1.0" encoding="utf-8"?>
<ScrollView 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:fillViewport="true">

    <androidx.constraintlayout.widget.ConstraintLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content">

        <TextView
            android:id="@+id/kbs_lock_pin_title"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:gravity="center_horizontal"
            android:text="@string/RegistrationLockFragment__enter_your_pin"
            android:textAppearance="@style/Signal.Text.HeadlineMedium"
            app:layout_constraintBottom_toTopOf="@id/kbs_lock_keyboard_toggle"
            app:layout_constraintTop_toTopOf="parent"
            app:layout_constraintVertical_bias="0.20" />

        <TextView
            android:id="@+id/kbs_lock_pin_description"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginStart="27dp"
            android:layout_marginTop="12dp"
            android:layout_marginEnd="27dp"
            android:gravity="center_horizontal"
            android:minHeight="66dp"
            android:text="@string/RegistrationLockFragment__enter_the_pin_you_created"
            android:textAppearance="@style/Signal.Text.BodyLarge"
            android:textColor="@color/signal_text_secondary"
            app:layout_constraintTop_toBottomOf="@id/kbs_lock_pin_title" />

        <EditText
            android:id="@+id/kbs_lock_pin_input"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center_horizontal"
            android:layout_marginTop="12dp"
            android:gravity="center_horizontal"
            android:inputType="numberPassword"
            android:minWidth="210dp"
            android:textColor="@color/signal_colorOnSurface"
            app:layout_constraintEnd_toEndOf="parent"
            app:layout_constraintStart_toStartOf="parent"
            app:layout_constraintTop_toBottomOf="@id/kbs_lock_pin_description" />

        <TextView
            android:id="@+id/kbs_lock_pin_input_label"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginTop="8dp"
            android:gravity="center_horizontal"
            android:textAppearance="@style/Signal.Text.BodyMedium"
            app:layout_constraintEnd_toEndOf="parent"
            app:layout_constraintStart_toStartOf="parent"
            app:layout_constraintTop_toBottomOf="@id/kbs_lock_pin_input"
            tools:text="@string/RegistrationLockFragment__incorrect_pin_try_again" />

        <com.google.android.material.button.MaterialButton
            android:id="@+id/kbs_lock_forgot_pin"
            style="@style/Signal.Widget.Button.Large.Secondary"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginStart="32dp"
            android:layout_marginEnd="32dp"
            android:text="@string/RegistrationLockFragment__forgot_pin"
            app:layout_constraintEnd_toEndOf="parent"
            app:layout_constraintStart_toStartOf="parent"
            app:layout_constraintTop_toBottomOf="@id/kbs_lock_pin_input_label" />

        <com.google.android.material.button.MaterialButton
            android:id="@+id/kbs_lock_keyboard_toggle"
            style="@style/Signal.Widget.Button.Large.Secondary"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            app:layout_constraintBottom_toTopOf="@id/kbs_lock_pin_confirm"
            app:layout_constraintTop_toBottomOf="@id/kbs_lock_forgot_pin"
            app:layout_constraintVertical_bias="0.0"
            tools:layout_editor_absoluteX="32dp"
            tools:text="Create Alphanumeric Pin" />

        <org.thoughtcrime.securesms.util.views.CircularProgressMaterialButton
            android:id="@+id/kbs_lock_pin_confirm"
            style="@style/Signal.Widget.Button.Large.Tonal"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginStart="32dp"
            android:layout_marginEnd="32dp"
            android:layout_marginBottom="16dp"
            app:circularProgressMaterialButton__label="@string/RegistrationActivity_continue"
            app:layout_constraintBottom_toBottomOf="parent"
            app:layout_constraintEnd_toEndOf="parent"
            app:layout_constraintHorizontal_bias="1.0"
            app:layout_constraintStart_toStartOf="parent"
            app:materialThemeOverlay="@style/ThemeOverlay.Signal.CircularProgressIndicator.Tonal" />

    </androidx.constraintlayout.widget.ConstraintLayout>
</ScrollView>