<?xml version="1.0"?>

-<RelativeLayout tools:context=".MainActivity" android:paddingTop="@dimen/activity_vertical_margin" android:paddingRight="@dimen/activity_horizontal_margin" android:paddingLeft="@dimen/activity_horizontal_margin" android:paddingBottom="@dimen/activity_vertical_margin" android:layout_height="match_parent" android:layout_width="match_parent" xmlns:tools="http://schemas.android.com/tools" xmlns:android="http://schemas.android.com/apk/res/android">

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

</RelativeLayout>

<?xml version="1.0"?>

-<RelativeLayout tools:context=".MainActivity" android:paddingTop="@dimen/activity_vertical_margin" android:paddingRight="@dimen/activity_horizontal_margin" android:paddingLeft="@dimen/activity_horizontal_margin" android:paddingBottom="@dimen/activity_vertical_margin" android:layout_height="match_parent" android:layout_width="match_parent" xmlns:tools="http://schemas.android.com/tools" xmlns:android="http://schemas.android.com/apk/res/android">

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

</RelativeLayout>

package com.itheima.news_listview.utils;

import java.util.ArrayList;

import android.content.Context;

import com.itheima.news_listview.R;

import com.itheima.news_listview.bean.NewsBean;

public class NewsUtils {

    //封装新闻的假数据到list中返回

    public static ArrayList<NewsBean> getAllNews(Context context) {

        ArrayList<NewsBean> arrayList = new ArrayList<NewsBean>();

        for(int i = 0 ;i <100;i++)

        {

            NewsBean newsBean = new NewsBean();

            newsBean.title ="谢霆锋经纪人：偷拍系侵权行为：";

            newsBean.des= "称谢霆锋隐私权收到侵犯，将保留追究法律责任";

            newsBean.news_url= "http://www.sina.cn";

            newsBean.icon = context.getResources().getDrawable(R.drawable.ic_launcher);//通过context对象将一个资源id转换成一个Drawable对象。

            arrayList.add(newsBean);

            NewsBean newsBean1 = new NewsBean();

            newsBean1.title ="知情人：王菲是谢霆锋心头最爱的人";

            newsBean1.des= "身边的人都知道谢霆锋最爱王菲，二人早有复合迹象";

            newsBean1.news_url= "http://www.baidu.cn";

            newsBean1.icon = context.getResources().getDrawable(R.drawable.icon);//通过context对象将一个资源id转换成一个Drawable对象。

            arrayList.add(newsBean1);

            NewsBean newsBean2 = new NewsBean();

            newsBean2.title ="热烈祝贺黑马74高薪就业";

            newsBean2.des= "74期平均薪资20000，其中有一个哥们超过10万，这些It精英都迎娶了白富美.";

            newsBean2.news_url= "http://www.itheima.com";

            newsBean2.icon = context.getResources().getDrawable(R.drawable.icon2);//通过context对象将一个资源id转换成一个Drawable对象。

            arrayList.add(newsBean2);

        }

        return arrayList;

    }

}

package com.itheima.news_listview.bean;

import android.graphics.Bitmap;

import android.graphics.drawable.Drawable;

public class NewsBean {

    public String title;

    public String des;

    public Drawable icon;

    public String news_url;

}

package com.itheima.news_listview.adapter;

import java.util.ArrayList;

import com.itheima.news_listview.R;

import com.itheima.news_listview.bean.NewsBean;

import android.content.Context;

import android.view.LayoutInflater;

import android.view.View;

import android.view.ViewGroup;

import android.webkit.WebView.FindListener;

import android.widget.BaseAdapter;

import android.widget.ImageView;

import android.widget.LinearLayout;

import android.widget.RelativeLayout;

import android.widget.TextView;

public class NewsAdapter extends BaseAdapter {

    private ArrayList<NewsBean> list;

    private Context context;

    //通过构造方法接受要显示的新闻数据集合

    public NewsAdapter(Context context,ArrayList<NewsBean> list){

        this.list = list;

        this.context = context;

    }

    @Override

    public int getCount() {

        return list.size();

    }

    @Override

    public Object getItem(int position) {

        return list.get(position);

    }

    @Override

    public long getItemId(int position) {

        return position;

    }

    @Override

    public View getView(int position, View convertView, ViewGroup parent) {

        View view = null;

        //1.复用converView优化listview,创建一个view作为getview的返回值用来显示一个条目

        if(convertView != null){

            view = convertView;

        }else {

            //context:上下文, resource:要转换成view对象的layout的id, root:将layout用root(ViewGroup)包一层作为codify的返回值,一般传null

//            view = View.inflate(context, R.layout.item_news_layout, null);//将一个布局文件转换成一个view对象

            //通过LayoutInflater将布局转换成view对象

//            view =  LayoutInflater.from(context).inflate(R.layout.item_news_layout, null);

            //通过context获取系统服务得到一个LayoutInflater，通过LayoutInflater将一个布局转换为view对象

            LayoutInflater layoutInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);

            view = layoutInflater.inflate(R.layout.item_news_layout, null);

        }

        //2.获取view上的子控件对象

        ImageView item_img_icon = (ImageView) view.findViewById(R.id.item_img_icon);

        TextView item_tv_des = (TextView) view.findViewById(R.id.item_tv_des);

        TextView item_tv_title = (TextView) view.findViewById(R.id.item_tv_title);

        //3.获取postion位置条目对应的list集合中的新闻数据，Bean对象

        NewsBean newsBean = list.get(position);

        //4.将数据设置给这些子控件做显示

        item_img_icon.setImageDrawable(newsBean.icon);//设置imageView的图片

        item_tv_title.setText(newsBean.title);

        item_tv_des.setText(newsBean.des);

        return view;

    }

}