<?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" tools:context="org.ntlab.developrx.JavaMainActivity"> <android.support.constraint.ConstraintLayout android:layout_width="match_parent" android:layout_height="match_parent"> <Button android:id="@+id/flowable_btn" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="flowable (Reactive Streams)" app:layout_constraintStart_toStartOf="parent" app:layout_constraintTop_toTopOf="parent" /> <Button android:id="@+id/observable_btn" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="observable" app:layout_constraintStart_toStartOf="parent" app:layout_constraintTop_toBottomOf="@id/flowable_btn" /> <Button android:id="@+id/just_btn" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="just" app:layout_constraintStart_toStartOf="parent" app:layout_constraintTop_toBottomOf="@id/observable_btn" /> <Button android:id="@+id/fromarray_btn" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="fromarray" app:layout_constraintStart_toStartOf="parent" app:layout_constraintTop_toBottomOf="@id/just_btn" /> <Button android:id="@+id/range_btn" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="range" app:layout_constraintStart_toStartOf="parent" app:layout_constraintTop_toBottomOf="@id/fromarray_btn" /> <Button android:id="@+id/interval_btn" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="interval" app:layout_constraintStart_toStartOf="parent" app:layout_constraintTop_toBottomOf="@id/range_btn" /> <Button android:id="@+id/timer_btn" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="timer" app:layout_constraintStart_toStartOf="parent" app:layout_constraintTop_toBottomOf="@id/interval_btn" /> <Button android:id="@+id/error_btn" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="error" app:layout_constraintStart_toStartOf="parent" app:layout_constraintTop_toBottomOf="@id/timer_btn" /> <Button android:id="@+id/map_btn" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="map" app:layout_constraintStart_toStartOf="parent" app:layout_constraintTop_toBottomOf="@id/error_btn" /> <Button android:id="@+id/empty_btn" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="empty" app:layout_constraintStart_toStartOf="parent" app:layout_constraintTop_toBottomOf="@id/map_btn" /> <Button android:id="@+id/flatmap_1_btn" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="flatmap(1)" app:layout_constraintStart_toStartOf="parent" app:layout_constraintTop_toBottomOf="@id/empty_btn" /> <Button android:id="@+id/flatmap_2_btn" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="flatmap(2)" app:layout_constraintStart_toStartOf="parent" app:layout_constraintTop_toBottomOf="@id/flatmap_1_btn" /> </android.support.constraint.ConstraintLayout> </ScrollView>