Android Recycleview与AnimatorSet实现画廊中卡片翻转效果

前言

前一段时间发现微信读书中卡片翻转的效果很炫酷。就仔细研究了一下卡片翻转的效果，就写了一个在画廊中实现图片翻转的Demo。

1.使用recycleview实现画廊效果

 //设置recycleview横向滑动
        LinearLayoutManager ms = new LinearLayoutManager(this);
        ms.setOrientation(LinearLayoutManager.HORIZONTAL);
        recycler.setLayoutManager(ms);

        cardRollingAdapter = new CardRollingAdapter(this,cardTextList);
        recycler.setAdapter(cardRollingAdapter);
        //实现像ViewPager一次滑动一页的效果
        new PagerSnapHelper().attachToRecyclerView(recycler);

2.实现item中卡片翻转的效果

2.1 item中的布局，由卡片的正反面组成。

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/ll_icontainer"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <FrameLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent">
        <LinearLayout
            android:id="@+id/back_layout"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:layout_marginLeft="15dp"
            android:layout_marginRight="15dp"
            android:layout_marginTop="45dp"
            android:layout_marginBottom="45dp"
            android:gravity="center"
            android:background="@drawable/sh_all_back_shadow">

            <TextView
                android:id="@+id/book_author"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:textColor="#0f1312"
                android:textSize="19sp"
                android:text="作者"/>

        </LinearLayout>

        <LinearLayout
            android:id="@+id/font_layout"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:layout_marginLeft="15dp"
            android:layout_marginRight="15dp"
            android:layout_marginTop="45dp"
            android:layout_marginBottom="45dp"
            android:gravity="center"
            android:background="@drawable/sh_all_red_shadow">

            <TextView
                android:id="@+id/book_title"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:textColor="#f7f7f7"
                android:textSize="19sp"
                android:text="书名"/>

        </LinearLayout>

    </FrameLayout>

</LinearLayout>

2.2 在adapter中的onBindViewHolder（@NonNull RollingHolder holder, int position）方法中对点击事件进行监听实现卡片翻转的效果。

 @Override
    public void onBindViewHolder(@NonNull RollingHolder holder, int position) {
    
        mRightOutSet = (AnimatorSet) AnimatorInflater.loadAnimator(context, R.anim.anim_out);
        mLeftInSet = (AnimatorSet) AnimatorInflater.loadAnimator(context, R.anim.anim_in);
        //设置数据
        holder.bookTitle.setText(mData.get(position).getFontText());
        holder.bookAuthor.setText(mData.get(position).getBackText());
        //设置正面不同的背景
        position++;
        if (position % 2 == 0){
            holder.fontLayout.setBackgroundResource(R.drawable.sh_all_white_shadow);
            holder.bookTitle.setTextColor(mContext.getResources().getColor(R.color.color_ff8a8s8s));
        }else{
            holder.fontLayout.setBackgroundResource(R.drawable.sh_all_red_shadow);
            holder.bookTitle.setTextColor(mContext.getResources().getColor(R.color.color_f7f7f7));
        }

        //对item 设置翻转动画
        holder.itemView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if (!mRightOutSet.isRunning() && !mLeftInSet.isRunning()){
                    String tag = "";
                    if (null == holder.ll_container.getTag()) {
                        tag = "back";
                        //设置视角距离  贴近屏幕
                        int distance = 16000;
                        float scale = mContext.getResources().getDisplayMetrics().density * distance;
                        holder.fontLayout.setCameraDistance(scale);
                        holder.backLayout.setCameraDistance(scale);
                    } else {
                        tag = holder.ll_container.getTag().toString();
                    }

                    if ("back".equals(tag)) {
                        mRightOutSet.setTarget(holder.fontLayout);
                        mLeftInSet.setTarget(holder.backLayout);
                        mRightOutSet.start();
                        mLeftInSet.start();
                        holder.ll_container.setTag("front");
                    } else {
                        mRightOutSet.setTarget(holder.backLayout);
                        mLeftInSet.setTarget(holder.fontLayout);
                        mRightOutSet.start();
                        mLeftInSet.start();
                        holder.ll_container.setTag("back");
                    }
                }

            }
        });


    }

2.3 动画的实现初始化右出(RightOut）和左入(LeftIn)使用动画集合AnimatorSet.。在Recycleview的 adapter中通过标记的形式设置动画的翻转动作。

 //左入动画
<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android">

    <!--消失-->
    <objectAnimator
        android:duration="0"
        android:propertyName="alpha"
        android:valueFrom="1.0"
        android:valueTo="0.0" />

    <!--旋转-->
    <objectAnimator
        android:duration="@integer/anim_length"
        android:propertyName="rotationY"
        android:valueFrom="-180"
        android:valueTo="0" />

    <!--出现-->
    <objectAnimator
        android:duration="0"
        android:propertyName="alpha"
        android:startOffset="@integer/anim_half_length"
        android:valueFrom="0.0"
        android:valueTo="1.0" />
</set>

//右出动画
<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android">
    <!--旋转-->
    <objectAnimator
        android:duration="@integer/anim_length"
        android:propertyName="rotationY"
        android:valueFrom="0"
        android:valueTo="180" />

    <!--消失-->
    <objectAnimator
        android:duration="0"
        android:propertyName="alpha"
        android:startOffset="@integer/anim_half_length"
        android:valueFrom="1.0"
        android:valueTo="0.0" />
</set>

3.动画效果

参考文章

https://blog.csdn.net/caroline_wendy/article/details/50756697