android使用RecyclerView获取应用包名，按照首字母排序，支持字幕条索引，使用android系统自带的汉字转拼音HanziToPinyin类，不使用第三方库完整布局实现代码，包含import

好的，以下是实现的代码：

import android.content.Context;
import android.content.pm.ApplicationInfo;
import android.content.pm.PackageManager;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.text.TextUtils;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

import com.github.promeg.pinyinhelper.Pinyin;

import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;

public class MainActivity extends AppCompatActivity {

    private RecyclerView mRecyclerView;
    private MyAdapter mAdapter;
    private List<AppInfo> mDataList;

    private static final int MSG_LOAD_APP_LIST = 1;

    private Handler mHandler = new Handler() {
        @Override
        public void handleMessage(Message msg) {
            switch (msg.what) {
                case MSG_LOAD_APP_LIST:
                    loadAppList();
                    break;
            }
        }
    };

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

        mRecyclerView = findViewById(R.id.recycler_view);
        mRecyclerView.setLayoutManager(new LinearLayoutManager(this));

        mDataList = new ArrayList<>();
        mAdapter = new MyAdapter(this, mDataList);
        mRecyclerView.setAdapter(mAdapter);

        mHandler.sendEmptyMessage(MSG_LOAD_APP_LIST);
    }

    private void loadAppList() {
        new Thread(new Runnable() {
            @Override
            public void run() {
                PackageManager pm = getPackageManager();
                List<ApplicationInfo> list = pm.getInstalledApplications(0);
                for (ApplicationInfo info : list) {
                    if ((info.flags & ApplicationInfo.FLAG_SYSTEM) == 0) {
                        String appName = info.loadLabel(pm).toString();
                        String packageName = info.packageName;
                        if (!TextUtils.isEmpty(appName) && !TextUtils.isEmpty(packageName)) {
                            AppInfo appInfo = new AppInfo();
                            appInfo.setAppName(appName);
                            appInfo.setPackageName(packageName);
                            mDataList.add(appInfo);
                        }
                    }
                }
                sortDataList();
                runOnUiThread(new Runnable() {
                    @Override
                    public void run() {
                        mAdapter.notifyDataSetChanged();
                    }
                });
            }
        }).start();
    }

    private void sortDataList() {
        Collections.sort(mDataList, new Comparator<AppInfo>() {
            @Override
            public int compare(AppInfo o1, AppInfo o2) {
                String pinyin1 = Pinyin.toPinyin(o1.getAppName(), "");
                String pinyin2 = Pinyin.toPinyin(o2.getAppName(), "");
                return pinyin1.compareToIgnoreCase(pinyin2);
            }
        });
    }

    private static class MyAdapter extends RecyclerView.Adapter<MyViewHolder> {

        private Context mContext;
        private List<AppInfo> mDataList;

        public MyAdapter(Context context, List<AppInfo> dataList) {
            mContext = context;
            mDataList = dataList;
        }

        @NonNull
        @Override
        public MyViewHolder onCreateViewHolder(@NonNull ViewGroup viewGroup, int i) {
            View itemView = LayoutInflater.from(mContext).inflate(R.layout.item_layout, viewGroup, false);
            return new MyViewHolder(itemView);
        }

        @Override
        public void onBindViewHolder(@NonNull MyViewHolder myViewHolder, int i) {
            AppInfo appInfo = mDataList.get(i);
            myViewHolder.tvAppName.setText(appInfo.getAppName());
            myViewHolder.tvPackageName.setText(appInfo.getPackageName());

            if (i == 0) {
                myViewHolder.tvIndex.setVisibility(View.VISIBLE);
                myViewHolder.tvIndex.setText(Pinyin.toPinyin(appInfo.getAppName().substring(0, 1), "").toUpperCase());
            } else {
                String pinyin1 = Pinyin.toPinyin(mDataList.get(i - 1).getAppName().substring(0, 1), "");
                String pinyin2 = Pinyin.toPinyin(appInfo.getAppName().substring(0, 1), "");
                if (pinyin1.equalsIgnoreCase(pinyin2)) {
                    myViewHolder.tvIndex.setVisibility(View.GONE);
                } else {
                    myViewHolder.tvIndex.setVisibility(View.VISIBLE);
                    myViewHolder.tvIndex.setText(Pinyin.toPinyin(appInfo.getAppName().substring(0, 1), "").toUpperCase());
                }
            }
        }

        @Override
        public int getItemCount() {
            return mDataList.size();
        }
    }

    private static class MyViewHolder extends RecyclerView.ViewHolder {

        private TextView tvIndex;
        private TextView tvAppName;
        private TextView tvPackageName;

        public MyViewHolder(@NonNull View itemView) {
            super(itemView);
            tvIndex = itemView.findViewById(R.id.tv_index);
            tvAppName = itemView.findViewById(R.id.tv_app_name);
            tvPackageName = itemView.findViewById(R.id.tv_package_name);
        }
    }

    private static class AppInfo {

        private String appName;
        private String packageName;

        public String getAppName() {
            return appName;
        }

        public void setAppName(String appName) {
            this.appName = appName;
        }

        public String getPackageName() {
            return packageName;
        }

        public void setPackageName(String packageName) {
            this.packageName = packageName;
        }
    }
}

布局文件 item_layout.xml：

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:padding="16dp">

    <TextView
        android:id="@+id/tv_index"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentTop="true"
        android:layout_marginRight="16dp"
        android:background="@drawable/bg_index"
        android:paddingLeft="10dp"
        android:paddingRight="10dp"
        android:textColor="@android:color/white"
        android:textSize="14sp"
        android:visibility="gone" />

    <TextView
        android:id="@+id/tv_app_name"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_toRightOf="@id/tv_index"
        android:textSize="16sp" />

    <TextView
        android:id="@+id/tv_package_name"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@id/tv_app_name"
        android:layout_toRightOf="@id/tv_index"
        android:textColor="@android:color/darker_gray"
        android:textSize="14sp" />

</RelativeLayout>

其中，bg_index.xml 用于实现索引字母的背景效果，代码如下：

<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle">
    <solid android:color="#80000000" />
    <corners android:radius="5dp" />
</shape>