TouTiao开源项目分析笔记13 最后一个订阅号的实现主页面

1.实现订阅号的基础类

1.1.本地订阅号的Bean类==>MediaChannelBean

public class MediaChannelBean implements Parcelable {

    public static final Creator<MediaChannelBean> CREATOR = new Creator<MediaChannelBean>() {

        @Override

        public MediaChannelBean createFromParcel(Parcel in) {

            return new MediaChannelBean(in);

        }

        @Override

        public MediaChannelBean[] newArray(int size) {

            return new MediaChannelBean[size];

        }

    };

    private String id;

    private String name;

    private String avatar;

    private String type;

    private String followCount;

    private String descText;

    private String url;

    public MediaChannelBean() {

    }

    protected MediaChannelBean(Parcel in) {

        id = in.readString();

        name = in.readString();

        avatar = in.readString();

        type = in.readString();

        followCount = in.readString();

        descText = in.readString();

        url = in.readString();

    }

    @Override

    public void writeToParcel(Parcel dest, int flags) {

        dest.writeString(id);

        dest.writeString(name);

        dest.writeString(avatar);

        dest.writeString(type);

        dest.writeString(followCount);

        dest.writeString(descText);

        dest.writeString(url);

    }

    @Override

    public int describeContents() {

        return 0;

    }

    public String getId() {

        return id;

    }

    public void setId(String id) {

        this.id = id;

    }

    public String getName() {

        return name;

    }

    public void setName(String name) {

        this.name = name;

    }

    public String getAvatar() {

        return avatar;

    }

    public void setAvatar(String avatar) {

        this.avatar = avatar;

    }

    public String getType() {

        return type;

    }

    public void setType(String type) {

        this.type = type;

    }

    public String getFollowCount() {

        return followCount;

    }

    public void setFollowCount(String followCount) {

        this.followCount = followCount;

    }

    public String getDescText() {

        return descText;

    }

    public void setDescText(String descText) {

        this.descText = descText;

    }

    public String getUrl() {

        return url;

    }

    public void setUrl(String url) {

        this.url = url;

    }

}

1.2.数据库建立订阅号的基础表==>MediaChannelTable　

public class MediaChannelTable {

    /**

     * 头条号信息表

     */

    public static final String TABLENAME = "MediaChannelTable";

    /**

     * 字段部分

     */

    public static final String ID = "id";

    public static final String NAME = "name";

    public static final String AVATAR = "avatar";

    public static final String TYPE = "type";

    public static final String FOLLOWCOUNT = "followCount";

    public static final String DESCTEXT = "descText";

    public static final String URL = "url";

    /**

     * 字段ID 数据库操作建立字段对应关系 从0开始

     */

    public static final int ID_ID = 0;

    public static final int ID_NAME = 1;

    public static final int ID_AVATAR = 2;

    public static final int ID_TYPE = 3;

    public static final int ID_FOLLOWCOUNT = 4;

    public static final int ID_DESCTEXT = 5;

    public static final int ID_URL = 6;

    /**

     * 创建表

     */

    public static final String CREATE_TABLE = "create table if not exists " + TABLENAME + "(" +

            ID + " text primary key, " +

            NAME + " text, " +

            AVATAR + " text, " +

            TYPE + " text, " +

            FOLLOWCOUNT + " text, " +

            DESCTEXT + " text, " +

            URL + " text) ";

}

1.3.实现最底层订阅号的数据库操作

public class MediaChannelDao {

    private SQLiteDatabase db;

    public MediaChannelDao(){

        this.db= DatabaseHelper.getDatabase();

    }

    public void initData(){

        add("4377795668", "新华网", "http://p2.pstatp.com/large/3658/7378365093", "news",

                "", "传播中国，报道世界；权威声音，亲切表达。", "http://toutiao.com/m4377795668/");

        add("52445544609", "互联网的这点事", "http://p3.pstatp.com/large/ef300164e786ff295da", "news",

                "", "每天为你速递最新、最鲜、最有料的互联网科技资讯！", "http://toutiao.com/m52445544609/");

    }

    public boolean add(String id,

                       String name,

                       String avatar,

                       String type,

                       String followCount,

                       String descText,

                       String url) {

        ContentValues values = new ContentValues();

        values.put(MediaChannelTable.ID, id);

        values.put(MediaChannelTable.NAME, name);

        values.put(MediaChannelTable.AVATAR, avatar);

        values.put(MediaChannelTable.TYPE, type);

        values.put(MediaChannelTable.FOLLOWCOUNT, followCount);

        values.put(MediaChannelTable.DESCTEXT, descText);

        values.put(MediaChannelTable.URL, url);

        long result = db.insert(MediaChannelTable.TABLENAME, null, values);

        return result != -1;

    }

    public List<MediaChannelBean> queryAll() {

        Cursor cursor = db.query(MediaChannelTable.TABLENAME, null, null, null, null, null, null);

        List<MediaChannelBean> list = new ArrayList<>();

        while (cursor.moveToNext()) {

            MediaChannelBean bean = new MediaChannelBean();

            bean.setId(cursor.getString(MediaChannelTable.ID_ID));

            bean.setName(cursor.getString(MediaChannelTable.ID_NAME));

            bean.setAvatar(cursor.getString(MediaChannelTable.ID_AVATAR));

            bean.setType(cursor.getString(MediaChannelTable.ID_TYPE));

            bean.setFollowCount(cursor.getString(MediaChannelTable.ID_FOLLOWCOUNT));

            bean.setDescText(cursor.getString(MediaChannelTable.ID_DESCTEXT));

            bean.setUrl(cursor.getString(MediaChannelTable.ID_URL));

            list.add(bean);

        }

        cursor.close();

        return list;

    }

    public boolean queryIsExist(String id) {

        Cursor cursor = db.query(MediaChannelTable.TABLENAME, null, MediaChannelTable.ID + "=?", new String[]{id}, null, null, null);

        if (cursor.moveToNext()) {

            cursor.close();

            return true;

        }

        cursor.close();

        return false;

    }

    public boolean delete(String mediaId) {

        int id = db.delete(MediaChannelTable.TABLENAME, MediaChannelTable.ID + "=?", new String[]{mediaId});

        return id != -1;

    }

}

2.构建订阅号视图页面

2.1.创建订阅号视图布局==>fragment_media.xml　

<?xml version="1.0" encoding="utf-8"?>

<LinearLayout

    xmlns:android="http://schemas.android.com/apk/res/android"

    xmlns:app="http://schemas.android.com/apk/res-auto"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    android:background="@color/windowBackground"

    android:orientation="vertical"

    app:layout_behavior="@string/appbar_scrolling_view_behavior">

    <android.support.v4.widget.SwipeRefreshLayout

        android:id="@+id/refresh_layout"

        android:layout_width="match_parent"

        android:layout_height="match_parent">

        <android.support.design.widget.CoordinatorLayout

            android:layout_width="match_parent"

            android:layout_height="match_parent">

            <TextView

                android:id="@+id/tv_desc"

                android:layout_width="wrap_content"

                android:layout_height="wrap_content"

                android:layout_gravity="center"

                android:text="@string/media_hint_desc"/>

            <android.support.v7.widget.RecyclerView

                android:id="@+id/recycler_view"

                android:layout_width="match_parent"

                android:layout_height="match_parent"

                android:fadeScrollbars="true"

                android:scrollbarFadeDuration="1"

                android:scrollbars="vertical"/>

        </android.support.design.widget.CoordinatorLayout>

    </android.support.v4.widget.SwipeRefreshLayout>

</LinearLayout>

　　预览图片：

2.2.定义一个长按监听事件==>长按弹出提示框　

public interface IOnItemLongClickListener {

    /**

     * RecyclerView Item长按事件

     */

    void onLongClick(View view, int position);

}

2.3.构建一个订阅号视图类　

public class MediaChannelView extends RxFragment implements SwipeRefreshLayout.OnRefreshListener {

    private static final String TAG = "MediaChannelView";

    private static MediaChannelView instance = null;

    private RecyclerView recyclerView;

    private SwipeRefreshLayout swipeRefreshLayout;

    private MultiTypeAdapter adapter;

    private MediaChannelDao dao = new MediaChannelDao();

    private TextView tv_desc;

    private String isFirstTime = "isFirstTime";

    private List<MediaChannelBean> list;

    public static MediaChannelView getInstance() {

        if (instance == null) {

            instance = new MediaChannelView();

        }

        return instance;

    }

    @Nullable

    @Override

    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {

        View view = inflater.inflate(R.layout.fragment_media, container, false);

        initView(view);

        initData();

        return view;

    }

    @Override

    public void onResume() {

        super.onResume();

        swipeRefreshLayout.setColorSchemeColors(SettingUtil.getInstance().getColor());

        setAdapter();

    }

    private void initData() {

        SharedPreferences editor = getActivity().getSharedPreferences(TAG, Context.MODE_PRIVATE);

        boolean result = editor.getBoolean(isFirstTime, true);

        if (result) {

            dao.initData();

            editor.edit().putBoolean(isFirstTime, false).apply();

        }

        setAdapter();

    }

    private void setAdapter() {

        Observable

                .create(new ObservableOnSubscribe<List<MediaChannelBean>>() {

                    @Override

                    public void subscribe(@NonNull ObservableEmitter<List<MediaChannelBean>> e) throws Exception {

                        list = dao.queryAll();

                        e.onNext(list);

                    }

                })

                .subscribeOn(Schedulers.io())

                .observeOn(AndroidSchedulers.mainThread())

                .compose(this.<List<MediaChannelBean>>bindUntilEvent(FragmentEvent.DESTROY))

                .subscribe(new Consumer<List<MediaChannelBean>>() {

                    @Override

                    public void accept(@NonNull List<MediaChannelBean> list) throws Exception {

                        adapter.setItems(list);

                        adapter.notifyDataSetChanged();

                        if (list.size() == 0) {

                            tv_desc.setVisibility(View.VISIBLE);

                        } else {

                            tv_desc.setVisibility(View.GONE);

                        }

                    }

                });

    }

    private void initView(View view) {

        recyclerView = view.findViewById(recycler_view);

        recyclerView.setHasFixedSize(true);

        recyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));

        swipeRefreshLayout = view.findViewById(R.id.refresh_layout);

        swipeRefreshLayout.setColorSchemeColors(SettingUtil.getInstance().getColor());

        swipeRefreshLayout.setOnRefreshListener(this);

        tv_desc = view.findViewById(R.id.tv_desc);

        IOnItemLongClickListener listener = new IOnItemLongClickListener() {

            @Override

            public void onLongClick(View view, int position) {

                final MediaChannelBean item = list.get(position);

                AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());

                builder.setMessage("取消订阅\" " + item.getName() + " \"?");

                builder.setPositiveButton(R.string.button_enter, new DialogInterface.OnClickListener() {

                    @Override

                    public void onClick(DialogInterface dialog, int which) {

                        new Thread(new Runnable() {

                            @Override

                            public void run() {

                                dao.delete(item.getId());

                                setAdapter();

                            }

                        }).start();

                        dialog.dismiss();

                    }

                });

                builder.setNegativeButton(R.string.button_cancel, new DialogInterface.OnClickListener() {

                    @Override

                    public void onClick(DialogInterface dialog, int which) {

                        dialog.dismiss();

                    }

                });

                builder.show();

            }

        };

        adapter = new MultiTypeAdapter();

        Register.registerMediaChannelItem(adapter, listener);

        recyclerView.setAdapter(adapter);

    }

    @Override

    public void onRefresh() {

        swipeRefreshLayout.setRefreshing(true);

        setAdapter();

        swipeRefreshLayout.setRefreshing(false);

    }

    @Override

    public void onDestroyView() {

        super.onDestroyView();

        if (instance != null) {

            instance = null;

        }

    }

}

　　注意：如果setAdapter简化成下面这个函数，直观效果一直。　

private void setAdapter(){

        list=dao.queryAll();

        adapter.setItems(list);

        adapter.notifyDataSetChanged();

        if (list.size() == 0) {

            tv_desc.setVisibility(View.VISIBLE);

        } else {

            tv_desc.setVisibility(View.GONE);

        }

    }

　　但是，如果订阅号的数量很多很多后，这种效果远远不如订阅的方法性能好。

　　所以我们统一就用订阅的方式吧。

　　而且更加重要的是，如果没有数据的时候，

　　这里要进行界面操作，如果直接在io线程会发生异常的。

2.4.发现Register中还没有注册类型以及传入监听求

 public static void registerMediaChannelItem(@NonNull MultiTypeAdapter adapter, @NonNull IOnItemLongClickListener listener) {

        adapter.register(MediaChannelBean.class, new MediaChannelViewBinder(listener));

    }

　　这里发现了监听器传进去了，说明绑定类中要给每一行都要设置这个listener

　　然后这里又看到MediaChannelViewBinder绑定类还没有实现呢！

　　第三点主要讲解这个简单的绑定类。

3.订阅号视图绑定类

3.1.首先看一下视图布局吧。==>item_media_channel.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:layout_width="match_parent"

    android:layout_height="wrap_content"

    android:background="@color/viewBackground">

    <LinearLayout

        android:id="@+id/content"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:background="?attr/selectableItemBackground"

        android:foreground="?attr/selectableItemBackground"

        android:padding="8dp">

        <com.meiji.toutiao.widget.CircleImageView

            android:id="@+id/cv_avatar"

            android:layout_width="52dp"

            android:layout_height="52dp"

            android:layout_gravity="center"

            android:scaleType="centerCrop"

            android:src="@color/textColorPrimary"/>

        <RelativeLayout

            android:layout_width="match_parent"

            android:layout_height="wrap_content"

            android:layout_gravity="center"

            android:layout_marginLeft="8dp"

            android:layout_marginStart="8dp">

            <TextView

                android:id="@+id/tv_mediaName"

                android:layout_width="wrap_content"

                android:layout_height="wrap_content"

                android:layout_alignParentLeft="true"

                android:layout_alignParentStart="true"

                android:layout_toLeftOf="@+id/tv_followCount"

                android:layout_toStartOf="@+id/tv_followCount"

                android:maxLines="1"

                android:textSize="16sp"

                android:textStyle="bold"

                tools:text="新华国际"/>

            <TextView

                android:id="@+id/tv_followCount"

                android:layout_width="wrap_content"

                android:layout_height="wrap_content"

                android:layout_alignParentEnd="true"

                android:layout_alignParentRight="true"

                android:text=""

                tools:text="111人关注"/>

            <TextView

                android:id="@+id/tv_descText"

                android:layout_width="wrap_content"

                android:layout_height="wrap_content"

                android:layout_below="@+id/tv_mediaName"

                android:layout_marginTop="4dp"

                android:ellipsize="end"

                android:maxLines="1"

                android:textSize="14sp"

                tools:text="中国军力超越日本 日本为什么不怕中国？普京一句话让国人顿悟"/>

        </RelativeLayout>

    </LinearLayout>

    <View

        android:id="@+id/divider"

        android:layout_width="match_parent"

        android:layout_height="1px"

        android:layout_below="@+id/content"

        android:background="@color/line_divider"/>

</RelativeLayout>

　　视图效果预览：

3.2.然后就是这个绑定类了==>MediaChannelViewBinder　

package com.jasonjan.headnews.binder.media;

import android.content.Context;

import android.support.annotation.NonNull;

import android.support.v7.widget.RecyclerView;

import android.view.LayoutInflater;

import android.view.View;

import android.view.ViewGroup;

import android.widget.TextView;

import com.jakewharton.rxbinding2.view.RxView;

import com.jasonjan.headnews.R;

import com.jasonjan.headnews.bean.media.MediaChannelBean;

import com.jasonjan.headnews.interfaces.IOnItemLongClickListener;

import com.jasonjan.headnews.main.ErrorAction;

import com.jasonjan.headnews.util.ImageLoader;

import com.jasonjan.headnews.widget.CircleImageView;

import java.util.concurrent.TimeUnit;

import io.reactivex.functions.Consumer;

import me.drakeet.multitype.ItemViewBinder;

/**

 * Created by JasonJan on 2017/12/14.

 */

public class MediaChannelViewBinder extends ItemViewBinder<MediaChannelBean,MediaChannelViewBinder.ViewHolder> {

    private IOnItemLongClickListener listener;

    public MediaChannelViewBinder(IOnItemLongClickListener listener) {

        this.listener = listener;

    }

    @NonNull

    @Override

    protected MediaChannelViewBinder.ViewHolder onCreateViewHolder(@NonNull LayoutInflater inflater, @NonNull ViewGroup parent) {

        View view = inflater.inflate(R.layout.item_media_channel, parent, false);

        return new ViewHolder(view, listener);

    }

    @Override

    protected void onBindViewHolder(@NonNull final ViewHolder holder, @NonNull final MediaChannelBean item){

        try {

            final Context context = holder.itemView.getContext();

            String url = item.getAvatar();

            ImageLoader.loadCenterCrop(context, url, holder.cv_avatar, R.color.viewBackground);

            holder.tv_mediaName.setText(item.getName());

            holder.tv_descText.setText(item.getDescText());

            RxView.clicks(holder.itemView)

                    .throttleFirst(1, TimeUnit.SECONDS)

                    .subscribe(new Consumer<Object>() {

                        @Override

                        public void accept(@io.reactivex.annotations.NonNull Object o) throws Exception {

                           // MediaHomeActivity.launch(item.getId());

                        }

                    });

        } catch (Exception e) {

            ErrorAction.print(e);

        }

    }

    public class ViewHolder extends RecyclerView.ViewHolder implements View.OnLongClickListener {

        private CircleImageView cv_avatar;

        private TextView tv_mediaName;

        private TextView tv_followCount;

        private TextView tv_descText;

        private IOnItemLongClickListener listener;

        public ViewHolder(View itemView, IOnItemLongClickListener listener) {

            super(itemView);

            this.cv_avatar = itemView.findViewById(R.id.cv_avatar);

            this.tv_mediaName = itemView.findViewById(R.id.tv_mediaName);

            this.tv_followCount = itemView.findViewById(R.id.tv_followCount);

            this.tv_descText = itemView.findViewById(R.id.tv_descText);

            this.listener = listener;

            itemView.setOnLongClickListener(this);

        }

        @Override

        public boolean onLongClick(View v) {

            if (listener != null) {

                listener.onLongClick(v, getLayoutPosition());

                return true;

            }

            return false;

        }

    }

}

　　这里先理一理RxView.clicks思路。

　　这个ViewHolder继承于RecyclerView.ViewHolder

　　绑定类由于继承ItemViewBinder，不得不去实现onBindViewHolder<T,这里面的ViewHolder>

　　所以在这里面处理ViewHolder的holdr.itemView的时候

　　要用到RxView.clicks(view)

　　如下方的代码:

RxView.clicks(holder.itemView)

                    .throttleFirst(1, TimeUnit.SECONDS)

                    .subscribe(new Consumer<Object>() {

                        @Override

                        public void accept(@io.reactivex.annotations.NonNull Object o) throws Exception {

                            MediaHomeActivity.launch(item.getId());

                        }

                    });

　　RxView代表着用了第三方库，结合了RxJava。

　　采用订阅的方式处理点击事件。

　　当然也可以不用这种方式，不过我还没发现这种方式的好处。

　　这里的ThrottleFirst操作符会定期发射这个时间段里源Observable发射的第一个数据。

　　参考博客：RxJava操作符（三）

4.效果预览

4.1.目前完成的工作

　　新闻的主页面三种大类型

　　图片的一种大类型（也只用了一种）

　　视频的一种大类型（采用了新闻主页面的其中一种）

　　订阅号的主页面的一种大类型（也只采用了一种）

　　然后还有一些点击事件，调转到相应的活动页面还未实现。

4.2.目前手机真实数据效果

巴特西

TouTiao开源项目分析笔记13 最后一个订阅号的实现主页面

1.实现订阅号的基础类

2.构建订阅号视图页面

3.订阅号视图绑定类

4.效果预览

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巴特西

TouTiao开源项目 分析笔记13 最后一个订阅号的实现主页面

1.实现订阅号的基础类

2.构建订阅号视图页面

3.订阅号视图绑定类

4.效果预览

最新文章

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TouTiao开源项目分析笔记13 最后一个订阅号的实现主页面