仿照探探卡片滑动

SlideCardLayoutManager

package com.enjoy.leo_slidecard;

import android.view.View;
import android.view.ViewGroup;

import androidx.recyclerview.widget.RecyclerView;

public class SlideCardLayoutManager extends RecyclerView.LayoutManager {

    @Override
    public RecyclerView.LayoutParams generateDefaultLayoutParams() {
        return new RecyclerView.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT,
                ViewGroup.LayoutParams.WRAP_CONTENT);
    }

    // 布局
    @Override
    public void onLayoutChildren(RecyclerView.Recycler recycler, RecyclerView.State state) {

        // ViewHodler回收复用
        detachAndScrapAttachedViews(recycler);

        int bottomPosition;
        int itemCount = getItemCount();
        if (itemCount < CardConfig.MAX_SHOW_COUNT) {
            bottomPosition = 0;
        } else {
            // 布局了四张卡片 --- 4，5，6，7
            bottomPosition = itemCount - CardConfig.MAX_SHOW_COUNT;
        }

        for (int i = bottomPosition; i < itemCount; i++) {
            // 复用
            View view = recycler.getViewForPosition(i);
            addView(view);

            measureChildWithMargins(view, 0, 0);

            int widthSpace = getWidth() - getDecoratedMeasuredWidth(view);
            int heightSpace = getHeight() - getDecoratedMeasuredHeight(view);

            // 布局 ---draw -- onDraw ,onDrawOver, onLayout
            layoutDecoratedWithMargins(view, widthSpace / 2, heightSpace / 2,
                    widthSpace / 2 + getDecoratedMeasuredWidth(view),
                    heightSpace / 2 + getDecoratedMeasuredHeight(view));

            int level = itemCount - i - 1;
            if (level > 0) {
                if (level < CardConfig.MAX_SHOW_COUNT - 1) {
                    view.setTranslationY(CardConfig.TRANS_Y_GAP * level);
                    view.setScaleX(1 - CardConfig.SCALE_GAP * level);
                    view.setScaleY(1 - CardConfig.SCALE_GAP * level);
                } else {
                    // 最下面的那个view 与前一个view 布局一样
                    view.setTranslationY(CardConfig.TRANS_Y_GAP * (level - 1));
                    view.setScaleX(1 - CardConfig.SCALE_GAP * (level - 1));
                    view.setScaleY(1 - CardConfig.SCALE_GAP * (level - 1));
                }
            }
        }


    }
}

SlideCallback

package com.enjoy.leo_slidecard;

import android.graphics.Canvas;
import android.util.Log;
import android.view.View;

import androidx.annotation.NonNull;
import androidx.recyclerview.widget.ItemTouchHelper;
import androidx.recyclerview.widget.RecyclerView;

import com.enjoy.leo_slidecard.adapter.UniversalAdapter;

import java.util.List;

public class SlideCallback extends ItemTouchHelper.SimpleCallback {

    private RecyclerView mRv;
    private UniversalAdapter<SlideCardBean> adapter;
    private List<SlideCardBean> mDatas;

    public SlideCallback(RecyclerView mRv,
                         UniversalAdapter<SlideCardBean> adapter, List<SlideCardBean> mDatas) {
        super(0, 15);
        this.mRv = mRv;
        this.adapter = adapter;
        this.mDatas = mDatas;
    }

    // drag  拖拽
    @Override
    public boolean onMove(@NonNull RecyclerView recyclerView, @NonNull RecyclerView.ViewHolder viewHolder, @NonNull RecyclerView.ViewHolder target) {
        return false;
    }

    // 滑动
    @Override
    public void onSwiped(@NonNull RecyclerView.ViewHolder viewHolder, int direction) {
        SlideCardBean remove = mDatas.remove(viewHolder.getLayoutPosition());
        mDatas.add(0, remove);
        adapter.notifyDataSetChanged();// onMeasure, onlayout
    }

    // onDraw


    @Override
    public void onChildDraw(@NonNull Canvas c, @NonNull RecyclerView recyclerView, @NonNull RecyclerView.ViewHolder viewHolder, float dX, float dY, int actionState, boolean isCurrentlyActive) {
        super.onChildDraw(c, recyclerView, viewHolder, dX, dY, actionState, isCurrentlyActive);


        double maxDistance = recyclerView.getWidth() * 0.5f;
        double distance = Math.sqrt(dX * dX + dY * dY);
        double fraction = distance / maxDistance;

        if (fraction > 1) {
            fraction = 1;
        }

        // 显示的个数  4个
        int itemCount = recyclerView.getChildCount();
        Log.i("SlideCallback",">>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>");
        Log.i("SlideCallback",""+distance);

        for (int i = 0; i < itemCount; i++) {
            Log.i("SlideCallback",""+distance+"    "+i);
            View view = recyclerView.getChildAt(i);

            int level = itemCount - i - 1;

            if (level > 0) {
                if (level < CardConfig.MAX_SHOW_COUNT - 1) {
                    view.setTranslationY((float) (CardConfig.TRANS_Y_GAP * level - fraction * CardConfig.TRANS_Y_GAP));
                    view.setScaleX((float) (1 - CardConfig.SCALE_GAP * level + fraction * CardConfig.SCALE_GAP));
                    view.setScaleY((float) (1 - CardConfig.SCALE_GAP * level + fraction * CardConfig.SCALE_GAP));
                }
            }
        }
        Log.i("SlideCallback","<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<");
    }

    @Override
    public long getAnimationDuration(@NonNull RecyclerView recyclerView, int animationType, float animateDx, float animateDy) {
        return 1500;
    }
}

CardConfig

public class CardConfig {
    //屏幕上最多同时显示几个Item
    public static int MAX_SHOW_COUNT;

    //每一级Scale相差0.05f，translationY相差7dp左右
    public static float SCALE_GAP;
    public static int TRANS_Y_GAP;

    public static void initConfig(Context context) {
        MAX_SHOW_COUNT = 4;
        SCALE_GAP = 0.05f;
        // 把非标准尺寸转换成标准尺寸
        TRANS_Y_GAP = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 15, context.getResources().getDisplayMetrics());
    }
}

MainActivity

package com.enjoy.leo_slidecard;

import androidx.appcompat.app.AppCompatActivity;
import androidx.recyclerview.widget.ItemTouchHelper;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.RecyclerView;

import android.os.Bundle;
import android.widget.ImageView;

import com.bumptech.glide.Glide;
import com.enjoy.leo_slidecard.adapter.UniversalAdapter;
import com.enjoy.leo_slidecard.adapter.ViewHolder;

import java.util.List;

public class MainActivity extends AppCompatActivity {

    private RecyclerView rv;
    private UniversalAdapter<SlideCardBean> adapter;
    private List<SlideCardBean> mDatas;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        rv = findViewById(R.id.rv);
        rv.setLayoutManager(new SlideCardLayoutManager());

        mDatas = SlideCardBean.initDatas();
        adapter = new UniversalAdapter<SlideCardBean>(this, mDatas, R.layout.item_swipe_card) {

            @Override
            public void convert(ViewHolder viewHolder, SlideCardBean slideCardBean) {
                viewHolder.setText(R.id.tvName, slideCardBean.getName());
                viewHolder.setText(R.id.tvPrecent, slideCardBean.getPostition() + "/" + mDatas.size());
                Glide.with(MainActivity.this)
                        .load(slideCardBean.getUrl())
                        .into((ImageView) viewHolder.getView(R.id.iv));
            }
        };
        rv.setAdapter(adapter);
        // 初始化数据
        CardConfig.initConfig(this);

        SlideCallback slideCallback = new SlideCallback(rv, adapter, mDatas);
        ItemTouchHelper itemTouchHelper = new ItemTouchHelper(slideCallback);
        itemTouchHelper.attachToRecyclerView(rv);

    }
}