android - 水平 RecylerView 看起来像 ViewPager

Question

我尝试将水平 RecylerView 转换为 ViewPager。
(工作方式类似于水平RecylerView，看起来像ViewPager)

我正在开发现有项目，其中水平 RecylerView 已经在使用，并且根据要求完美工作，但我需要更改它的设计，因为 RecylerView 是水平的，一次只应显示一项，以便用户更好地理解我需要在项目下方添加一个线性布局，该布局显示 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:在水平 recylerview 中滚动时如何获取指示器中项目的当前位置？

尝试和错误:

我不知道如何在滚动时获取当前项目的位置？
(我在单击项目时获取项目的位置)

我可以使用viewpager代替水平recylerview，但是使用是多次的，我需要在很多地方改变它(时间和精力)。
(我已经根据总项目设置了指示器，但我无法获取项目的位置)

注意:一次仅显示一项

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，这两种方法使我的工作变得轻松..

 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项时，我们可以使用它来代替 viewpager。