关于安卓实现新闻发布

来源：互联网发布：软件开发资质证书编辑：程序博客网时间：2024/06/06 01:14

1.activity_main.xml文件如下：

<?xml version="1.0"encoding="utf-8"?><RelativeLayoutxmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:id="@+id/activity_main" android:layout_width="match_parent" android:layout_height="match_parent" tools:context="cn.edu.bzu.anew.MainActivity">

<FrameLayout android:layout_width="match_parent" android:layout_height="match_parent">

<ProgressBar android:layout_width="wrap_content" android:layout_height="wrap_content"/>

</LinearLayout>

<ListView android:id="@+id/lv_news" android:layout_width="match_parent" android:layout_height="match_parent"/>

</FrameLayout>

</RelativeLayout>

news_item.xml文件如下：

<?xml version="1.0"encoding="utf-8"?><RelativeLayoutxmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="65dp">

<com.loopj.android.image.SmartImageView android:id="@+id/siv_icon" android:layout_width="80dp" android:layout_height="60dp" android:scaleType="centerCrop" android:src="@mipmap/ic_launcher" android:layout_alignParentLeft="true" android:layout_alignParentStart="true"></com.loopj.android.image.SmartImageView>

</RelativeLayout>

2.新建一个名为adapter的包名，新建一个NewsAdapter的类，内容如下：

package cn.edu.bzu.anew.adapter;importandroid.content.Context;importandroid.support.annotation.NonNull;importandroid.view.LayoutInflater;importandroid.view.View;importandroid.view.ViewGroup;importandroid.widget.ArrayAdapter;importandroid.widget.TextView;importcom.loopj.android.image.SmartImageView;importjava.util.List;import cn.edu.bzu.anew.R;import cn.edu.bzu.anew.entity.NewsInfo;

public class NewsAdapterextends ArrayAdapter<NewsInfo>{

public NewsAdapter(Context context, List<NewsInfo> objects) {

super(context, R.layout.news_item, objects);

}

@NonNull @Override publicView getView(int position, View convertView, ViewGroup parent) {

NewsInfo newsinfo= getItem(position);//传递position，获取当前位置对应的newsinfo新闻信息 View view=null;

viewHolder viewHolder;

if(convertView==null){//判断convertView中是否加载了布局，有没有缓存。为空说明没有缓存 view=LayoutInflater.from(getContext()).inflate(R.layout.news_item,null);

viewHolder=new viewHolder();

viewHolder.siv= (SmartImageView) view.findViewById(R.id.siv_icon);

viewHolder.tv_title= (TextView) view.findViewById(R.id.tv_title);

viewHolder.tv_description= (TextView) view.findViewById(R.id.tv_description);

viewHolder.tv_type= (TextView) view.findViewById(R.id.tv_type);

view.setTag(viewHolder); //保存 }else{

view=convertView;

viewHolder=(viewHolder) view.getTag();

}

viewHolder.siv.setImageUrl(newsinfo.getIcon());

viewHolder.tv_title.setText(newsinfo.getTitle());//传递题目 viewHolder.tv_description.setText(newsinfo.getDescription());

viewHolder.tv_type.setText(newsinfo.getType()+"");

return view;

}

class viewHolder{//添加类，封装需要查找的控件 TextViewtv_title;

TextView tv_description;

TextView tv_type;

SmartImageView siv;

}

3.新建一个名为entity的包名，新建一个NewsInfo的类，内容如下：

package cn.edu.bzu.anew.entity;public classNewsInfo {

private String icon;

private String title;

private String description;

private int type;

private long comment;

public NewsInfo(String icon, String title, String description,int type, longcomment) {

this.icon= icon;

this.title= title;

this.description= description;

this.type= type;

this.comment= comment;

}

public String getIcon() {

return icon;

}

public void setIcon(String icon) {

this.icon= icon;

}

public String getTitle() {

return title;

}

public void setTitle(String title) {

this.title= title;

}

public String getDescription() {

return description;

}

public void setDescription(String description) {

this.description= description;

}

public int getType() {

return type;

}

public void setType(inttype) {

this.type= type;

}

public long getComment() {

return comment;

}

public void setComment(longcomment) {

this.comment= comment;

}

4.新建一个名为Tools的包，包下新建一个名为JsonParse的类，内容如下：

package cn.edu.bzu.anew.Tools;importcom.google.gson.Gson;importcom.google.gson.reflect.TypeToken;importjava.lang.reflect.Type;importjava.util.List;import cn.edu.bzu.anew.entity.NewsInfo;

/** * Created by Administrator on 2017/5/18. */public classJsonParse {

public static List<NewsInfo>getNewsInfo(String json){

Gson gson =new Gson();

Type listType=new TypeToken<List<NewsInfo>> (){

}.getType();

List<NewsInfo>newsInfos=gson.fromJson(json,listType);

return newsInfos;

}

5.MainActivity的内容如下：

package cn.edu.bzu.anew;

import android.support.v7.app.AppCompatActivity;importandroid.os.Bundle;importandroid.view.View;importandroid.widget.LinearLayout;importandroid.widget.ListView;importandroid.widget.Toast;importcom.loopj.android.http.AsyncHttpClient;importcom.loopj.android.http.AsyncHttpResponseHandler;importjava.io.UnsupportedEncodingException;importjava.util.List;import cn.edu.bzu.anew.Tools.JsonParse;importcn.edu.bzu.anew.adapter.NewsAdapter;importcn.edu.bzu.anew.entity.NewsInfo;

public class MainActivityextends AppCompatActivity {

private ListView lvNews;

private List<NewsInfo> newsInfos;

private LinearLayoutloading;

@Override protected voidonCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

lvNews=(ListView)findViewById(R.id.lv_news);

loading=(LinearLayout)findViewById(R.id.loading);

fillData();

}

private void fillData(){

AsyncHttpClient client =new AsyncHttpClient();

client.get("http://10.51.9.254:8080/NewsInfo.json",newAsyncHttpResponseHandler(){

@Override public voidonSuccess(int i, org.apache.http.Header[] headers,byte[] bytes) {

try{

String json=new String(bytes,"utf-8");

newsInfos= JsonParse.getNewsInfo(json);

if(newsInfos==null){

Toast.makeText(MainActivity.this,"解析失败", Toast.LENGTH_LONG).show();

}else{

loading .setVisibility(View.INVISIBLE);

lvNews.setAdapter(newNewsAdapter(MainActivity.this,newsInfos));

}

} catch (UnsupportedEncodingException e) {

e.printStackTrace();

}

@Override public voidonFailure(int i, org.apache.http.Header[] headers,byte[] bytes, Throwable throwable) {

}

} );

}

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