how to Use RecyclerView.ItemAnimator With RecyclerView

Question

I am a beginner in Android Development. When I search for RecyclerView animation, I have found about RecyclerView.ItemAnimator and but I can't find any tutorial on how to use this. I have read this How to use ItemAnimator in a RecyclerView?. But still, I don't get anything.

I have found documentation.

By default, RecyclerView uses DefaultItemAnimator.

What type of animation can expect from DefaultItemAnimator If I use RecyclerView?

I have used LayoutAnimation, When should I use RecyclerView.ItemAnimator?

The default item animator works when updating your `RecycleView`. Let's say when you delete, add or update. For eg., the animation in Gmail or Messages when you delete. — sanjeev, Nov 21 '19 at 09:51
Oh sorry. I am weak in English too. could you please give me more information. What you mean by that? — Athira Reddy, Nov 21 '19 at 09:58
Alright. A simple yet visually understanding way would be to refer this library https://github.com/wasabeef/recyclerview-animators. This is how an item animator works. — sanjeev, Nov 21 '19 at 10:04
I have seen most of the site use DefaultItemAnimator like this recyclerView.setItemAnimator(new DefaultItemAnimator());, If it is default, then why they need to implement like this? — Athira Reddy, Dec 06 '19 at 11:00
Let's call it an additional functionality to default one! :) — sanjeev, Dec 07 '19 at 11:19

Jasurbek · Answer 1 · 2019-11-21T12:42:28.830

You can use Any type of animation to animate your recycler view item

Required steps to build the following behavior

Start off by creating the file item_animation_fall_down.xml in res/anim/ and add the following:

<set xmlns:android="http://schemas.android.com/apk/res/android"
     android:duration="@integer/anim_duration_medium">

    <translate
        android:fromYDelta="-20%"
        android:toYDelta="0"
        android:interpolator="@android:anim/decelerate_interpolator"
        />

    <alpha
        android:fromAlpha="0"
        android:toAlpha="1"
        android:interpolator="@android:anim/decelerate_interpolator"
        />

    <scale
        android:fromXScale="105%"
        android:fromYScale="105%"
        android:toXScale="100%"
        android:toYScale="100%"
        android:pivotX="50%"
        android:pivotY="50%"
        android:interpolator="@android:anim/decelerate_interpolator"
        />

</set>

Defining the LayoutAnimation

With the item animation done it’s time to define the layout animation which will apply the item animation to each child in the layout. Create a new file called layout_animation_fall_down.xml in res/anim/ and add the following:

<?xml version="1.0" encoding="utf-8"?>
<layoutAnimation
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:animation="@anim/item_animation_fall_down"
    android:delay="15%"
    android:animationOrder="normal"
    />

Applying the LayoutAnimation

A LayoutAnimation can be applied both programmatically and in XML.

JAVA

int resId = R.anim.layout_animation_fall_down;
LayoutAnimationController animation = AnimationUtils.loadLayoutAnimation(ctx, resId);
recyclerview.setLayoutAnimation(animation);

XML

<android.support.v7.widget.RecyclerView
    android:layout_width="match_parent"
    android:layout_height="match_parent"                                        
    android:layoutAnimation="@anim/layout_animation_fall_down"
    />

For more info visit here

You can use ItemAnimator to apply default animation or create a class then extend ItemAnimator and apply your desired animation, after all, set created class as a default animation — Jasurbek, Nov 21 '19 at 10:49

score 0 · Answer 2 · answered Nov 21 '19 at 09:36

0

You wish to animate rows of recyclerview. Use below function

 public void setFadeAnimation(View view) {
    AlphaAnimation anim = new AlphaAnimation(0.0f, 1.0f);
    anim.setDuration(1000);
    view.startAnimation(anim);
}

Now Go to Adapter class and call this function like this inside onBindViewHolder method

setFadeAnimation(myViewHolder.itemView);

It will animate your rows

answered Nov 21 '19 at 09:36

Sanwal Singh

1,765
3
17
35

1

Thank you for your answer. But I want to know what is the use of ItemAnimator? When should I use? – Athira Reddy Nov 21 '19 at 09:48

how to Use RecyclerView.ItemAnimator With RecyclerView

2 Answers2