新闻详情页实现

一、效果

 

 二、设计思路

1、通过点击新闻列表跳转到新闻详情界面是使用，intent，携带这条新闻的一些必要参数（eg：url）。

2、使用jsoup解析html，获取新闻的图片和正文信息。

3、使用一个listView来展示用户的评论。（评论区、输入框都可以实现，显示/隐藏的切换）

参考：https://blog.csdn.net/yypccc/article/details/52168311

view.setVisibility(View.VISIBLE);// 显示评
viewview.setVisibility(View.GONE);// 隐藏评view

三、代码

1、新闻详情页布局：

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context=".NewsActivity">

    <com.me.view.MyImageView
        android:id="@+id/iv_new_dg"
        android:layout_width="match_parent"
        android:layout_height="200dp"
        android:scaleType="fitXY"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintVertical_bias="0.05" />

    <ScrollView
        android:id="@+id/scrollView2"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        app:layout_constraintBottom_toTopOf="@+id/linearLayout"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/iv_new_dg">

        <TextView
            android:id="@+id/tv_zw"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="123"
            android:textSize="24dp" />
    </ScrollView>

    <LinearLayout
        android:id="@+id/linearLayout"
        android:layout_width="match_parent"
        android:layout_height="200dp"
        android:orientation="horizontal"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintVertical_bias="1.0" >
        <include layout="@layout/activity_comment" />
    </LinearLayout>

</androidx.constraintlayout.widget.ConstraintLayout>

2、评论区布局：

<RelativeLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <ListView
        android:id="@+id/comment_list"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_marginTop="10dp"
        android:layout_marginBottom="50dp" />

    <LinearLayout
        android:id="@+id/rl_enroll"
        android:layout_width="match_parent"
        android:layout_height="50dp"
        android:orientation="horizontal"
        android:layout_alignParentBottom="true"
        android:background="#ffffff">

        <ImageView
            android:id="@+id/comment"
            android:layout_width="32dp"
            android:layout_height="32dp"
            android:src="@drawable/comment"
            android:layout_weight="1"
            android:layout_gravity="center" />

        <ImageView
            android:id="@+id/chat"
            android:layout_width="23dp"
            android:layout_height="23dp"
            android:src="@drawable/chat"
            android:layout_weight="1"
            android:layout_gravity="center"/>
    </LinearLayout>

    <RelativeLayout
        android:id="@+id/rl_comment"
        android:layout_width="match_parent"
        android:layout_height="50dp"
        android:background="#ffffff"
        android:visibility="gone"
        android:layout_alignParentBottom="true">

        <View
            android:layout_width="match_parent"
            android:layout_height="1dp"
            android:background="#969696" />

        <TextView
            android:id="@+id/hide_down"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="隐藏"
            android:textSize="13sp"
            android:textColor="#E91E63"
            android:drawableBottom="@drawable/hide_dowm"
            android:layout_alignParentLeft="true"
            android:layout_centerVertical="true"
            android:layout_marginLeft="10dp"/>
        <View
            android:layout_width="1dp"
            android:layout_height="match_parent"
            android:background="#969696"
            android:layout_toRightOf="@id/hide_down"
            android:layout_marginLeft="10dp"/>
        <EditText
            android:id="@+id/comment_content"
            android:hint="评论"
            android:textSize="15sp"
            android:singleLine="true"
            android:layout_width="240dp"
            android:layout_height="match_parent"
            android:background="@null"
            android:layout_toRightOf="@id/hide_down"
            android:layout_marginLeft="20dp"/>

        <Button
            android:id="@+id/comment_send"
            android:layout_width="50dp"
            android:layout_height="35dp"
            android:layout_margin="5dp"
            android:text="发送"
            android:textSize="13sp"
            android:textColor="#ffffff"
            android:background="#E91E63"
            android:layout_alignParentRight="true"
            android:layout_marginRight="10dp"
            android:layout_marginLeft="15dp"/>
    </RelativeLayout>
</RelativeLayout>

3、评论项的简单布局：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="horizontal"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <TextView
        android:id="@+id/comment_name"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textColor="#969696"
        android:textSize="24sp"
        android:layout_marginLeft="15dp"
        android:layout_marginRight="3dp"/>

    <TextView
        android:id="@+id/comment_content"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textColor="@color/colorAccent"
        android:textSize="24sp" />

</LinearLayout>

4、评论的实体类：

package com.me.domain;

public class Comment {

    String name; //评论者
    String content; //评论内容

    public Comment(){

    }

    public Comment(String name, String content){
        this.name = name;
        this.content = content;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getContent() {
        return content;
    }

    public void setContent(String content) {
        this.content = content;
    }
}

5、评论区的适配器：

package com.me.adapter;

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.TextView;

import com.me.domain.Comment;
import com.me.news.R;

import java.util.List;

public class AdapterComment extends BaseAdapter {

    Context context;
    List<Comment> data;

    public AdapterComment(Context c, List<Comment> data){
        this.context = c;
        this.data = data;
    }

    @Override
    public int getCount() {
        return data.size();
    }

    @Override
    public Object getItem(int i) {
        return data.get(i);
    }

    @Override
    public long getItemId(int i) {
        return i;
    }

    @Override
    public View getView(int i, View convertView, ViewGroup viewGroup) {
        ViewHolder holder;
        // 重用convertView
        if(convertView == null){
            holder = new ViewHolder();
            convertView = LayoutInflater.from(context).inflate(R.layout.item_comment, null);
            holder.comment_name = (TextView) convertView.findViewById(R.id.comment_name);
            holder.comment_content = (TextView) convertView.findViewById(R.id.comment_content);

            convertView.setTag(holder);
        }else{
            holder = (ViewHolder) convertView.getTag();
        }
        // 适配数据
        holder.comment_name.setText(data.get(i).getName());
        holder.comment_content.setText(data.get(i).getContent());

        return convertView;
    }

    /**
     * 添加一条评论,刷新列表
     * @param comment
     */
    public void addComment(Comment comment){
        data.add(comment);
        notifyDataSetChanged();
    }

    /**
     * 静态类，便于GC回收
     */
    public static class ViewHolder{
        TextView comment_name;
        TextView comment_content;
    }
}

6、新闻页的逻辑代码activity：

package com.me.news;

import androidx.appcompat.app.AppCompatActivity;

import android.content.Context;
import android.os.Bundle;
import android.view.View;
import android.view.inputmethod.InputMethodManager;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.ListView;
import android.widget.RelativeLayout;
import android.widget.TextView;
import android.widget.Toast;

import com.me.adapter.AdapterComment;
import com.me.domain.Comment;

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

public class CommentActivity extends AppCompatActivity implements View.OnClickListener{

    private ImageView comment;
    private ImageView chat;
    private TextView hide_down;
    private EditText comment_content;
    private Button comment_send;

    private LinearLayout rl_enroll;
    private RelativeLayout rl_comment;

    private ListView comment_list;
    private AdapterComment adapterComment;
    private List<Comment> data;


    private void initView() {

        // 初始化评论列表
        comment_list =  findViewById(R.id.comment_list);
        // 初始化数据
        data = new ArrayList<>();
        // 初始化适配器
        adapterComment = new AdapterComment(getApplicationContext(), data);
        // 为评论列表设置适配器
        comment_list.setAdapter(adapterComment);

        comment = findViewById(R.id.comment);
        hide_down =  findViewById(R.id.hide_down);
        comment_content = findViewById(R.id.comment_content);
        comment_send = findViewById(R.id.comment_send);

        rl_enroll =  findViewById(R.id.rl_enroll);
        rl_comment =  findViewById(R.id.rl_comment);
        chat = findViewById(R.id.chat);
        setListener();
    }

    /**
     * 设置监听
     */
    public void setListener(){
        comment.setOnClickListener(this);
        hide_down.setOnClickListener(this);
        comment_send.setOnClickListener(this);
        chat.setOnClickListener(this);
    }




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

    @Override
    public void onClick(View v) {
        switch (v.getId()) {
            case R.id.comment:
                // 弹出输入法
                InputMethodManager imm = (InputMethodManager) getApplicationContext().getSystemService(Context.INPUT_METHOD_SERVICE);
                imm.toggleSoftInput(0, InputMethodManager.HIDE_NOT_ALWAYS);
                // 显示评论框
                rl_enroll.setVisibility(View.GONE);
                rl_comment.setVisibility(View.VISIBLE);
                break;
            case R.id.hide_down:
                // 隐藏评论框
                rl_enroll.setVisibility(View.VISIBLE);
                rl_comment.setVisibility(View.GONE);
                // 隐藏输入法，然后暂存当前输入框的内容，方便下次使用
                InputMethodManager im = (InputMethodManager)getApplicationContext().getSystemService(Context.INPUT_METHOD_SERVICE);
                im.hideSoftInputFromWindow(comment_content.getWindowToken(), 0);
                break;
            case R.id.comment_send:
                sendComment();
                break;
            case R.id.chat:
                if(View.GONE==comment_list.getVisibility()){
                    comment_list.setVisibility(View.GONE);
                }else{
                    comment_list.setVisibility(View.VISIBLE);
                }

            default:
                break;
        }

    }
    /**
     * 发送评论
     */
    public void sendComment(){
        if(comment_content.getText().toString().equals("")){
            Toast.makeText(getApplicationContext(), "评论不能为空！", Toast.LENGTH_SHORT).show();
        }else{
            // 生成评论数据
            Comment comment = new Comment();
            comment.setName("评论者"+(data.size()+1)+"：");
            comment.setContent(comment_content.getText().toString());
            adapterComment.addComment(comment);
            // 发送完，清空输入框
            comment_content.setText("");

            Toast.makeText(getApplicationContext(), "评论成功！", Toast.LENGTH_SHORT).show();
        }
    }

}

初步成果......