How to implement collapsing toolbar with tablayout like Watsapp

Question

Xml File

<?xml version="1.0" encoding="utf-8"?>
<androidx.coordinatorlayout.widget.CoordinatorLayout 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=".MainActivity">

    <com.google.android.material.appbar.AppBarLayout
        android:id="@+id/app_bar_layout"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:fitsSystemWindows="true"
        android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar">


        <com.google.android.material.appbar.CollapsingToolbarLayout
            android:id="@+id/collapsingToolbar"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            app:layout_scrollFlags="scroll|exitUntilCollapsed">

            <androidx.appcompat.widget.Toolbar
                android:id="@+id/toolbar"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
               >

                <TextView
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:text="@string/app_name"
                    android:textSize="22sp"
                    android:textColor="@color/black"
                    />

            </androidx.appcompat.widget.Toolbar>

        </com.google.android.material.appbar.CollapsingToolbarLayout>

        <com.google.android.material.tabs.TabLayout
            android:id="@+id/tab_layout"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            app:layout_collapseMode="pin"
            />

    </com.google.android.material.appbar.AppBarLayout>

    <androidx.viewpager2.widget.ViewPager2
        android:id="@+id/view_pager"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:layout_behavior="com.google.android.material.appbar.AppBarLayout$ScrollingViewBehavior"/>

</androidx.coordinatorlayout.widget.CoordinatorLayout>

In Watsapp home screen, when user scrolls up the toolbar disappears and only tablayout is visible. I was just trying to implement this feature. I went through a lot of youtube tutorial but could not find any solution.

something like this - https://i.stack.imgur.com/76m5h.gif

Answer 1

Put your toolbar inside of a CollapsingToolbarLayout

Add app:layout_scrollFlags="scroll|exitUntilCollapsed" to the collapsing toolbar

Remove app:layout_collapseMode="pin" from your toolbar

Add app:layout_collapseMode="pin" to the tablayout

Add app:layout_behavior="com.google.android.material.appbar.AppBarLayout$ScrollingViewBehavior" to your viewpager