android_multiviewwer/app/src/main/res/layout/booktoki.xml

<?xml version="1.0" encoding="utf-8"?>
<layout>
        <androidx.constraintlayout.widget.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"
            >

                <bums.lunatic.launcher.tokiz.view.BWebview
                    android:id="@+id/menu_web"
                    android:layout_margin="5dp"
                    android:layout_width="match_parent"
                    android:layout_height="0dp"
                    app:layout_constraintLeft_toLeftOf="parent"
                    app:layout_constraintRight_toRightOf="parent"
                    app:layout_constraintBottom_toBottomOf="parent"
                    app:layout_constraintTop_toBottomOf="@id/textview_title" />

                <androidx.constraintlayout.utils.widget.ImageFilterButton
                    android:id="@+id/btn_home"
                    android:layout_width="wrap_content"
                    android:layout_height="@dimen/main_top_height"
                    android:background="@android:color/transparent"
                    android:adjustViewBounds="true"
                    android:scaleType="fitCenter"
                    android:src="@drawable/home"
                    app:layout_constraintLeft_toLeftOf="parent"
                    app:layout_constraintTop_toTopOf="parent"
                    tools:ignore="MissingConstraints" />


                <TextView
                    android:id="@+id/textview_title"
                    android:layout_width="0dp"
                    android:layout_height="@dimen/main_top_height"
                    android:text="@string/app_name"
                    android:gravity="center"
                    android:textColor="@color/white"
                    android:textSize="18sp"
                    app:layout_constraintRight_toLeftOf="@id/btn_list"
                    app:layout_constraintLeft_toRightOf="@id/btn_setting"
                    app:layout_constraintTop_toTopOf="parent" />

                <androidx.constraintlayout.utils.widget.ImageFilterButton
                    android:background="@android:color/transparent"
                    android:id="@+id/btn_list"
                    android:layout_width="wrap_content"
                    android:layout_height="@dimen/main_top_height"
                    android:adjustViewBounds="true"
                    android:scaleType="centerInside"
                    android:src="@drawable/bookmark"
                    app:layout_constraintTop_toTopOf="parent"
                    app:layout_constraintLeft_toRightOf="@id/textview_title"
                    app:layout_constraintRight_toLeftOf="@+id/btn_history"
                    app:layout_constraintHorizontal_chainStyle="spread_inside"
                    />

                <androidx.constraintlayout.utils.widget.ImageFilterButton
                    android:id="@+id/btn_history"
                    android:layout_width="wrap_content"
                    android:layout_height="@dimen/main_top_height"
                    android:adjustViewBounds="true"
                    android:scaleType="fitCenter"
                    android:src="@drawable/saved"
                    android:background="@android:color/transparent"
                    app:layout_constraintRight_toRightOf="parent"
                    app:layout_constraintTop_toTopOf="parent"
                    app:layout_constraintHorizontal_chainStyle="spread_inside"
                    />



                <androidx.constraintlayout.utils.widget.ImageFilterButton
                    android:id="@+id/btn_setting"
                    android:layout_width="wrap_content"
                    android:src="@drawable/settings"
                    android:layout_height="@dimen/main_top_height"
                    android:scaleType="fitCenter"
                    android:adjustViewBounds="true"
                    android:background="@android:color/transparent"
                    app:layout_constraintLeft_toRightOf="@+id/btn_home"
                    app:layout_constraintTop_toTopOf="parent"
                    app:layout_constraintHorizontal_chainStyle="spread"
                    />


                <bums.lunatic.launcher.tokiz.view.PagedTextLayout
                    android:id="@+id/paged_layer"
                    android:layout_margin="1dp"
                    android:layout_width="0dp"
                    android:layout_height="0dp"
                    android:orientation="vertical"
                    android:visibility="gone"
                    android:elevation="5dp"
                    app:layout_constraintLeft_toLeftOf="parent"
                    app:layout_constraintRight_toRightOf="parent"
                    app:layout_constraintBottom_toBottomOf="parent"
                    app:layout_constraintTop_toBottomOf="@id/textview_title" />

                <ProgressBar
                    android:id="@+id/progress"
                    android:layout_width="0dp"
                    android:layout_height="0dp"
                    android:layout_gravity="center"
                    android:layout_marginTop="48dp"
                    android:indeterminate="false"
                    android:max="100"
                    android:progressBackgroundTint="#FBE7C6"
                    android:progressDrawable="@drawable/circle_progressbar"
                    android:progressTint="#edbf41"
                    android:visibility="gone"
                    app:layout_constraintBottom_toBottomOf="parent"
                    app:layout_constraintEnd_toEndOf="parent"
                    app:layout_constraintStart_toStartOf="parent"
                    app:layout_constraintTop_toTopOf="parent" />

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