Hide/Show bottomNavigationView on Scroll

问题:

I have to hide bottom navigation view on up scroll and show on down scroll .how to implement this? my layout is like this

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent">


    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical"
        android:layout_above="@+id/navigation"
        android:layout_alignParentTop="true"
        android:layout_marginBottom="5dp">

        <FrameLayout
            android:id="@+id/container1"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
          />


    </LinearLayout>

    <android.support.design.widget.BottomNavigationView
        android:id="@+id/navigation"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:background="?android:attr/windowBackground"
        app:layout_scrollFlags="scroll|enterAlways|snap"
        app:menu="@menu/dashboard_slider_menu" />

</RelativeLayout>

I have attached screenshot of view. Kindly check it.

回答1:

UPDATE

Update to latest Support Library Version 28.0.0 or higher version and just add one attribute to BottomNavigationView.

<BottomNavigationView
 ....
 ....
 app:layout_behavior="@string/hide_bottom_view_on_scroll_behavior"/>

Note:- Your XML should follow the structure of XML given below in old answer.

OLD ANSWER(Still Works)

You need a helper class to do this .This solution works like Google Material Design Guideline.

Create a class BottomNavigationViewBehavior

public class BottomNavigationViewBehavior extends CoordinatorLayout.Behavior<BottomNavigationView> {

    private int height;

    @Override
    public boolean onLayoutChild(CoordinatorLayout parent, BottomNavigationView child, int layoutDirection) {
        height = child.getHeight();
        return super.onLayoutChild(parent, child, layoutDirection);
    }

    @Override
    public boolean onStartNestedScroll(@NonNull CoordinatorLayout coordinatorLayout,
                                   BottomNavigationView child, @NonNull 
                                   View directTargetChild, @NonNull View target,
                                   int axes, int type)
    {
        return axes == ViewCompat.SCROLL_AXIS_VERTICAL;
    }

    @Override
    public void onNestedScroll(@NonNull CoordinatorLayout coordinatorLayout, @NonNull BottomNavigationView child,
               @NonNull View target, int dxConsumed, int dyConsumed,
               int dxUnconsumed, int dyUnconsumed, 
                @ViewCompat.NestedScrollType int type)
    {
       if (dyConsumed > 0) {
           slideDown(child);
       } else if (dyConsumed < 0) {
           slideUp(child);
       }
    }

    private void slideUp(BottomNavigationView child) {
        child.clearAnimation();
        child.animate().translationY(0).setDuration(200);
    }

    private void slideDown(BottomNavigationView child) {
        child.clearAnimation();
        child.animate().translationY(height).setDuration(200);
    }
}

For using this behavior you need to use cooradinator layout...

<android.support.v4.widget.DrawerLayout 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:id="@+id/drawer_layout"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="com.kliff.digitaldwarka.activity.MainActivity">

    <android.support.design.widget.CoordinatorLayout
        android:id="@+id/coordinator_layout"
        android:layout_width="match_parent"
        android:layout_height="match_parent">

        <android.support.design.widget.AppBarLayout
            android:id="@+id/myAppBar"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:descendantFocusability="beforeDescendants"
            android:focusableInTouchMode="true"
            android:theme="@style/AppTheme.AppBarOverlay"
            app:elevation="0dp">

            <android.support.v7.widget.Toolbar
                android:id="@+id/toolbar"
                android:layout_width="match_parent"
                android:layout_height="?attr/actionBarSize"
                android:background="?attr/colorPrimary"
                app:contentInsetStart="0dp"
                app:layout_scrollFlags="scroll|enterAlways"
                app:popupTheme="@style/AppTheme.PopupOverlay"/>
        </android.support.design.widget.AppBarLayout>

        <!---your RecyclerView/Fragment Container Layout-->
        <FrameLayout
             android:id="@+id/container"
             android:layout_width="match_parent"
             android:layout_height="match_parent"
             app:layout_behavior="@string/appbar_scrolling_view_behavior" />


         <android.support.design.widget.BottomNavigationView
             android:id="@+id/bottom_nav"
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
             android:layout_gravity="bottom"
             app:itemBackground="@color/white"
             app:menu="@menu/bottom_nav_menu" />

      </android.support.design.widget.CoordinatorLayout>

      <!---NavigationView-->
</android.support.v4.widget.DrawerLayout>

Add this code to your Activity that contains bottom nav..

mBottomNavigationView = (BottomNavigationView) findViewById(R.id.bottom_nav);
CoordinatorLayout.LayoutParams layoutParams = (CoordinatorLayout.LayoutParams) mBottomNavigationView.getLayoutParams();
    layoutParams.setBehavior(new BottomNavigationViewBehavior());

回答2:

Try this,

 mRecyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
            @Override
            public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
                if (dy > 0 && bottom_navigation.isShown()) {
                    bottom_navigation.setVisibility(View.GONE);
                } else if (dy < 0 ) {
                    bottom_navigation.setVisibility(View.VISIBLE);

                }
            }

            @Override
            public void onScrollStateChanged(RecyclerView recyclerView, int newState) {

                super.onScrollStateChanged(recyclerView, newState);
            }
        });

Image while scrolling up :-

Image while scrolling down:

回答3:

Updated answer after the latest library updates:

Hiding the BottomNavigationView on scrolling is now available with just one flag in the layout! Starting from version 28.0.0-alpha1 or the material/androidX 1.0.0-alpha1.

I updated my project using the latter approach since the version now is a stable release candidate. Update: Use fully released version "1.0.0"!

The new out of the box available behaviour is called HideBottomViewOnScrollBehavior. Set it on the BottomNavigationView as app:layout_behavior="@string/hide_bottom_view_on_scroll_behavior" as described in the latest docs.

Here is a full example:

<com.google.android.material.bottomnavigation.BottomNavigationView
        android:id="@+id/navigation"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        app:labelVisibilityMode="selected"
        app:layout_behavior="@string/hide_bottom_view_on_scroll_behavior"
        android:layout_gravity="bottom"
        app:layout_insetEdge="bottom"
        app:menu="@menu/navigation" />

As with the hiding of the Toolbar on scrolling, you have to ensure that the content is a class that supports the latest scrolling like RecyclerView and NestedScrollView.

This ensures all is working as shown in the animation on the design specs

PS: labelVisibilityMode is another cool addition you get for free for taking the trouble of updating and that is described in depth in the design specs.

回答4:

1. Update your project to Androidx i.e Refactor >> Migrate to androidx (Minimum Android studio version 3.4)
2. Using the default Bottom Navigation Menu xml file, replace the parent Constraint Layout with Coordinator layout.
3. Add the line app:layout_behavior="com.google.android.material.behavior.HideBottomViewOnScrollBehavior"

i.e

<?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:id="@+id/container"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".dashboards.Admin_dashboard_main">

    <include layout="@layout/toolbar" />
    <androidx.constraintlayout.widget.ConstraintLayout
        android:id="@+id/main_area"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:layout_constraintTop_toBottomOf="@+id/toolbar"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        android:layout_margin="0dp"
        android:padding="0dp">

        <!-- Fragments Container -->
        <FrameLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            app:layout_behavior="@string/appbar_scrolling_view_behavior"
            tools:context="MainActivity"
            tools:showIn="@layout/activity_tenant_dashboard"
            android:id="@+id/fragment_container">

        </FrameLayout>

    </androidx.constraintlayout.widget.ConstraintLayout>
    <!-- Bottom Navigation View -->

    <com.google.android.material.bottomnavigation.BottomNavigationView
        android:id="@+id/navigation"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginStart="0dp"
        android:layout_marginEnd="0dp"
        android:background="?android:attr/windowBackground"
        android:layout_gravity="bottom"
        app:menu="@menu/menu_admin_dashboard_main"
        app:layout_behavior="com.google.android.material.behavior.HideBottomViewOnScrollBehavior"
        />

</androidx.coordinatorlayout.widget.CoordinatorLayout>

回答5:

Use this

mRecyclerView.addOnScrollListener(new RecyclerView.OnScrollListener()
        {
            @Override
            public void onScrolled(RecyclerView recyclerView, int dx, int dy)
            {
                if (dy > 0 ||dy<0 && csButtonLay.isShown())
                {
                    bottomBar.setVisibility(View.GONE);
                }
            }

            @Override
            public void onScrollStateChanged(RecyclerView recyclerView, int newState)
            {
                if (newState == RecyclerView.SCROLL_STATE_IDLE)
                {
                    bottomBar.setVisibility(View.VISIBLE);
                }

                super.onScrollStateChanged(recyclerView, newState);
            }
        });

回答6:

Just use CoordinatorLayout as a parent container and add the app:layout_behavior in the child View and set the behavior @string/hide_bottom_view_on_scroll_behavior this is the solution.

<?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"
    android:orientation="vertical"
    tools:context=".Main2Activity">

    <androidx.recyclerview.widget.RecyclerView
        android:id="@+id/recyclerView"
        android:layout_width="match_parent"
        android:layout_above="@id/nav_view"
        android:layout_height="wrap_content"
        app:layoutManager="androidx.recyclerview.widget.LinearLayoutManager" />
    <com.google.android.material.bottomnavigation.BottomNavigationView
        android:id="@+id/nav_view"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:layout_gravity="bottom"
        app:layout_behavior="@string/hide_bottom_view_on_scroll_behavior"
        android:background="?android:attr/windowBackground"
        app:menu="@menu/bottom_nav_menu" />
</androidx.coordinatorlayout.widget.CoordinatorLayout>

Happy Coding.