水平 RecyclerView 看起来像 ViewPager

Question

我尝试将水平 RecylerView 转换为 ViewPager。
（像水平 RecylerView 一样工作看起来像 ViewPager）

我正在处理现有项目，其中水平 RecylerView 已经在使用中并且根据要求完美运行，但我需要更改它的设计，因为 RecylerView 是水平的，一次应该只显示一个项目，以便用户更好理解我需要在项目下方添加一个线性布局，它显示 RecylerView 中总项目的指示器（就像 ViewPager）。指示器的用途，它显示 RecylerView 中当前存在的项目。

我的问题：如何在水平回收视图中滚动时获取指示器中项目的当前位置？

试错：

我不知道如何在滚动时获取当前项目的位置？
（我在点击项目时得到了项目的位置）

我可以使用 viewpager 而不是 horizontal recylerview，但用途是多种我需要在很多地方（时间和精力）进行更改。
（我已经根据总项目设置了指标，但我无法获得项目的位置）

注意: 一次只显示一项

提前致谢。

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/rl"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:padding="16dp"
    tools:context=".MainActivity"
    android:background="#f7eaf9">

    <android.support.v7.widget.RecyclerView
        android:id="@+id/recycler_view"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="#fd7d7d">
    </android.support.v7.widget.RecyclerView>

    <LinearLayout
        android:id="@+id/linlay_pager"
        android:layout_margin="10dp"
        android:layout_below="@+id/recycler_view"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true"
        android:orientation="horizontal"/>
</RelativeLayout>

MainActivity.java

package com.horizontalrecyclerview;

import android.app.Activity;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.graphics.Color;
import android.os.Bundle;
import android.support.graphics.drawable.VectorDrawableCompat;
import android.support.v4.content.LocalBroadcastManager;
import android.support.v4.view.ViewPager;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.support.v7.widget.SnapHelper;
import android.view.Gravity;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.RelativeLayout;

import java.util.ArrayList;
import java.util.List;
import java.util.Random;

public class MainActivity extends AppCompatActivity {

    private Context mContext;
    private Activity mActivity;
    private Button pre;
    private RelativeLayout mRelativeLayout;
    private RecyclerView mRecyclerView;
    private RecyclerView.LayoutManager mLayoutManager;
    private RecyclerView.Adapter mAdapter;
    private Random mRandom = new Random();
    private LinearLayout linlay_pager;
    private VectorDrawableCompat mVectorPagerFillCircle;
    private VectorDrawableCompat mVectorPagerCircle;

    private BroadcastReceiver mBroadcastReceiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            int receivedColor = intent.getIntExtra("Color", Color.WHITE);
            mRelativeLayout.setBackgroundColor(receivedColor);
        }
    };

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        linlay_pager= (LinearLayout) findViewById(R.id.linlay_pager);
        mVectorPagerFillCircle = VectorDrawableCompat.create(getResources(), R.drawable.ic_pager_fill_circle, null);
        mVectorPagerCircle = VectorDrawableCompat.create(getResources(), R.drawable.ic_pager_circle, null);
        mContext = getApplicationContext();
        mActivity = MainActivity.this;
        LocalBroadcastManager.getInstance(mContext).registerReceiver(
                mBroadcastReceiver,
                new IntentFilter("BROADCAST_COLOR")
        );
        mRelativeLayout = (RelativeLayout) findViewById(R.id.rl);
        mRecyclerView = (RecyclerView) findViewById(R.id.recycler_view);

        SnapHelper snapHelper = new GravitySnapHelper(Gravity.START);
        snapHelper.attachToRecyclerView(mRecyclerView);

        mLayoutManager = new LinearLayoutManager(mContext, LinearLayoutManager.HORIZONTAL, false);
        mRecyclerView.setLayoutManager(mLayoutManager);

        List<String> colors = new ArrayList<>();
        for (int i = 0; i < 5; i++) {
            colors.add(getRandomHSVColor() + "");
        }

        LinearLayout.LayoutParams imParams = new LinearLayout.LayoutParams(ViewPager.LayoutParams.WRAP_CONTENT, ViewPager.LayoutParams.WRAP_CONTENT);
        for (int i = 0; i < 5; i++) {
            ImageView mImageCirclePager = new ImageView(this);
            if (i == 0) {
                mImageCirclePager.setImageDrawable(mVectorPagerFillCircle);
            } else {
                mImageCirclePager.setImageDrawable(mVectorPagerCircle);
            }
            linlay_pager.addView(mImageCirclePager, imParams);
        }

        mAdapter = new ColorsAdapter(mContext, colors);
        mRecyclerView.setAdapter(mAdapter);
    }

    public int getRandomHSVColor() {
        int hue = mRandom.nextInt(361);
        float saturation = 1.0f;
        float value = 1.0f;
        int alpha = 255;
        int color = Color.HSVToColor(alpha, new float[]{hue, saturation, value});
        return color;
    }
}

Answer 1

我找到了解决方案，这两种方法让我的工作变得轻松..

 mRecyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
            @Override
            public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
                super.onScrollStateChanged(recyclerView, newState);
                int pos = ((LinearLayoutManager)(recyclerView.getLayoutManager())).findFirstVisibleItemPosition();
                btnAction(pos,5);
            }
        }); 




private void btnAction(int position, int bannerListSize) {
            for (int i = 0; i < bannerListSize; i++) {
                ImageView imageView = (ImageView) linlay_pager.getChildAt(i);
                if (i == position) {
                    imageView.setImageDrawable(mVectorPagerFillCircle);
                } else {
                    imageView.setImageDrawable(mVectorPagerCircle);
                }
            }
        }

注意：当我们只需要显示一个项目时，我们可以用它代替viewpager。

水平 RecyclerView 看起来像 ViewPager

Horizontal RecylerView look as ViewPager

android

scrollview

viewpagerindicator

android-recyclerview