private lateinit var keyboardHelper: KeyboardHelper
keyboardHelper = KeyboardHelper()
        keyboardHelper.init(this)
            .bindRootLayout(layout_main)
            .bindBodyLayout(layout_body)
            .bindInputPanel(chat_input_panel)
            .bindExpressionPanel(expression_panel)
            .bindMorePanel(more_panel)
            .setKeyboardHeight(
                if (App.instance.keyboardHeight == 0) DensityUtil.getScreenHeight(applicationContext) / 5 * 2 else App.instance.keyboardHeight
            )
            .setOnKeyboardStateListener(object : KeyboardHelper.OnKeyboardStateListener {
                override fun onOpened(keyboardHeight: Int) {
                    App.instance.keyboardHeight = keyboardHeight
                }

                override fun onClosed() {
                }
            })

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:id="@+id/layout_main"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:clipChildren="false"
        android:orientation="vertical"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintTop_toBottomOf="@id/top_bar">

        <LinearLayout
            android:id="@+id/layout_body"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:orientation="vertical">

            <androidx.recyclerview.widget.RecyclerView
                android:id="@+id/recycler_view"
                android:layout_width="match_parent"
                android:layout_height="0dp"
                android:layout_weight="1"
                android:background="#333333" />

            <com.freddy.kulakeyboard.sample.CInputPanel
                android:id="@+id/chat_input_panel"
                android:layout_width="match_parent"
                android:layout_height="wrap_content" />
        </LinearLayout>

        <com.freddy.kulakeyboard.sample.CExpressionPanel
            android:id="@+id/expression_panel"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:visibility="invisible" />

        <com.freddy.kulakeyboard.sample.CMorePanel
            android:id="@+id/more_panel"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:visibility="invisible" />
    </LinearLayout>

    <TextView
        android:id="@+id/top_bar"
        android:layout_width="match_parent"
        android:layout_height="48dp"
        android:background="#00bfcf"
        android:gravity="center"
        android:textStyle="bold"
        android:text="TopBar"
        android:textColor="#000000"
        android:textSize="18sp"
        app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>

Copyright 2020, chenshichao

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

   http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.