类似于网易新闻客户端的界面实现02

上篇博文中点击打开链接我们已经实现了网易新闻的大概视图，但是这次的实现和上次有点不同，但是大体的思路都是一样的。

和上篇博文中的唯一不同是：

上篇博文中我们是在ActionBar中通过添加Tab的方式添加titles，并实现Tab的监听事件

而在本篇博文中我们实现的是在布局文件中添加titles并添加点击事件

好了，我们直接看代码吧。

一、首先是activity_main.xml文件：

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:orientation="vertical" >    <LinearLayout        android:layout_width="match_parent"        android:layout_height="0dp"        android:layout_weight="1"        android:background="#f00"        android:orientation="vertical" >        <TextView            android:layout_width="match_parent"            android:layout_height="0dp"            android:layout_marginBottom="10dp"            android:layout_marginLeft="10dp"            android:layout_weight="1"            android:gravity="bottom"            android:text="网易新闻"            android:textSize="16sp" />    </LinearLayout>    <LinearLayout        android:id="@+id/layout"        android:layout_width="match_parent"        android:layout_height="0dp"        android:layout_weight="1"        android:gravity="center"        android:orientation="horizontal" >        <TextView            android:layout_width="0dp"            android:layout_height="wrap_content"            android:layout_weight="1"            android:gravity="center"            android:text="国际" />        <TextView            android:layout_width="0dp"            android:layout_height="wrap_content"            android:layout_weight="1"            android:gravity="center"            android:text="军事" />        <TextView            android:layout_width="0dp"            android:layout_height="wrap_content"            android:layout_weight="1"            android:gravity="center"            android:text="体育" />        <TextView            android:layout_width="0dp"            android:layout_height="wrap_content"            android:layout_weight="1"            android:gravity="center"            android:text="娱乐" />        <TextView            android:layout_width="0dp"            android:layout_height="wrap_content"            android:layout_weight="1"            android:gravity="center"            android:text="科技" />    </LinearLayout>    <android.support.v4.view.ViewPager        android:id="@+id/viewPager"        android:layout_width="match_parent"        android:layout_height="0dp"        android:layout_weight="8" >    </android.support.v4.view.ViewPager></LinearLayout>

二、MainActivity：

package com.example.text_01;import java.io.Serializable;import java.util.ArrayList;import java.util.List;import com.example.text_01_bean.Data;import com.example.text_01_http.HttpUtils;import android.os.AsyncTask;import android.os.Bundle;import android.app.Activity;import android.graphics.Color;import android.support.v4.app.Fragment;import android.support.v4.app.FragmentActivity;import android.support.v4.app.FragmentManager;import android.support.v4.app.FragmentPagerAdapter;import android.support.v4.view.ViewPager;import android.support.v4.view.ViewPager.OnPageChangeListener;import android.view.Menu;import android.view.View;import android.view.Window;import android.widget.LinearLayout;import android.widget.TextView;public class MainActivity extends FragmentActivity {private ViewPager viewPager;private LinearLayout layout;private MyFragment fragment;private List<Fragment> fragments;private TextView titles[];@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);requestWindowFeature(Window.FEATURE_NO_TITLE);setContentView(R.layout.activity_main);viewPager = (ViewPager) findViewById(R.id.viewPager);layout = (LinearLayout) findViewById(R.id.layout);// 初始化List<Fragment>initFragment();// 初始化标题栏initTitles();// 设置viewPager的适配器，需要传一个SupportFragmentManager管理者对象viewPager.setAdapter(new MyAdapter(getSupportFragmentManager()));// 给ViewPager设置监听事件viewPager.setOnPageChangeListener(new OnPageChangeListener() {// 当我们滚动屏幕时，设置title显示不同的颜色@Overridepublic void onPageSelected(int arg0) {// 其他位置设置为灰色for (int i = 0; i < titles.length; i++) {titles[i].setTextColor(Color.GRAY);}// 当前所处界面的title设置为红色titles[arg0].setTextColor(Color.RED);}@Overridepublic void onPageScrolled(int arg0, float arg1, int arg2) {}@Overridepublic void onPageScrollStateChanged(int arg0) {}});}// 初始化标题栏private void initTitles() {// 设置标题长度titles = new TextView[fragments.size()];// 初始化标题for (int i = 0; i < titles.length; i++) {// 根据线性布局控件的getChildAt(index)方法得到TextViewtitles[i] = (TextView) layout.getChildAt(i);// 设置一个标记便于添加点击事件titles[i].setTag(i);titles[i].setTextColor(Color.GRAY);// 给标题设置监听事件，点击标题时进行相应页面的切换titles[i].setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {viewPager.setCurrentItem((Integer) v.getTag());}});}// 默认设置0角标为红色titles[0].setTextColor(Color.RED);}// 初始化List<Fragment>private void initFragment() {fragments = new ArrayList<Fragment>();for (int i = 0; i < 5; i++) {fragment = new MyFragment();// 传一个索引给FragmentBundle bundle = new Bundle();bundle.putSerializable("tabIndex", i);fragment.setArguments(bundle);fragments.add(fragment);}}// 设置适配器class MyAdapter extends FragmentPagerAdapter {public MyAdapter(FragmentManager fm) {super(fm);}@Overridepublic Fragment getItem(int arg0) {return fragments.get(arg0);}@Overridepublic int getCount() {return fragments.size();}}}

三、接下来就是在v4包下的Fragment的子类中实现网络数据的加载，这里为了增加用户体验，在Fragment的布局文件fragment中，我们除了添加一个

ListView外，还添加了一个TextView，我们设置当ListView中没有加载数据时，在界面显示TextView“正在加载。。。”

fragment布局文件：

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:gravity="center"    android:orientation="vertical" >    <ListView        android:id="@+id/lv"        android:layout_width="match_parent"        android:layout_height="match_parent" />    <TextView        android:id="@+id/tv"        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:gravity="center"        android:text="正在加载..."        android:textSize="20sp" /></LinearLayout>

接下来是MyFragment：

package com.example.text_01;import java.net.HttpURLConnection;import java.net.MalformedURLException;import java.net.URL;import java.util.List;import android.graphics.Bitmap;import android.graphics.BitmapFactory;import android.os.AsyncTask;import android.os.Bundle;import android.support.v4.app.Fragment;import android.view.LayoutInflater;import android.view.View;import android.view.ViewGroup;import android.widget.BaseAdapter;import android.widget.ImageView;import android.widget.ListView;import android.widget.TextView;import com.example.text_01_bean.Data;import com.example.text_01_http.HttpUtils;public class MyFragment extends Fragment {private ListView lv;private List<Data> list;private Data data;private TextView tv;// 我们解析Json数据的网址private String path[] = new String[] {"http://litchiapi.jstv.com/api/GetFeeds?column=4&PageSize=20&pageIndex=1&val=100511D3BE5301280E0992C73A9DEC41","http://litchiapi.jstv.com/api/GetFeeds?column=5&PageSize=20&pageIndex=1&val=100511D3BE5301280E0992C73A9DEC41","http://litchiapi.jstv.com/api/GetFeeds?column=6&PageSize=20&pageIndex=1&val=100511D3BE5301280E0992C73A9DEC41","http://litchiapi.jstv.com/api/GetFeeds?column=7&PageSize=20&pageIndex=1&val=100511D3BE5301280E0992C73A9DEC41","http://litchiapi.jstv.com/api/GetFeeds?column=8&PageSize=20&pageIndex=1&val=100511D3BE5301280E0992C73A9DEC41", };@Overridepublic View onCreateView(LayoutInflater inflater, ViewGroup container,Bundle savedInstanceState) {View view = inflater.inflate(R.layout.fragment, null);lv = (ListView) view.findViewById(R.id.lv);tv = (TextView) view.findViewById(R.id.tv);// 当ListView中还没有内容时，设置界面显示TextViewlv.setEmptyView(tv);// 得到传来的索引的值，根据不同的索引加载不同的网络数据Bundle bundle = getArguments();int tabIndex = bundle.getInt("tabIndex");switch (tabIndex) {case 0:new MyTask().execute(path[0]);break;case 1:new MyTask().execute(path[1]);break;case 2:new MyTask().execute(path[2]);break;case 3:new MyTask().execute(path[3]);break;case 4:new MyTask().execute(path[4]);break;default:break;}return view;}// 异步任务加载数据得到List<Data>集合class MyTask extends AsyncTask<String, Void, List<Data>> {@SuppressWarnings("unchecked")@Overrideprotected List<Data> doInBackground(String... params) {list = HttpUtils.getList(params[0]);return list;}@Overrideprotected void onPostExecute(List<Data> result) {super.onPostExecute(result);// 给ListView设置适配器lv.setAdapter(new MyAdapter());}}// 创建自定义适配器class MyAdapter extends BaseAdapter {@Overridepublic int getCount() {return list.size();}@Overridepublic Object getItem(int position) {return list.get(position);}@Overridepublic long getItemId(int position) {return position;}@Overridepublic View getView(int position, View convertView, ViewGroup parent) {final ViewHolder holder;if (convertView == null) {holder = new ViewHolder();convertView = LayoutInflater.from(getActivity()).inflate(R.layout.item, null);holder.tvSubject = (TextView) convertView.findViewById(R.id.tv_subject);holder.tvSummary = (TextView) convertView.findViewById(R.id.tv_summary);holder.tvChanged = (TextView) convertView.findViewById(R.id.tv_changed);holder.ivCover = (ImageView) convertView.findViewById(R.id.iv_cover);convertView.setTag(holder);} else {holder = (ViewHolder) convertView.getTag();}data = list.get(position);holder.tvChanged.setText(data.getChanged());holder.tvSubject.setText(data.getSubject());holder.tvSummary.setText(data.getSummary());String path = data.getCover();new ImageTask(new ImageCallback() {@Overridepublic void send(Bitmap bitmap, String path) {holder.ivCover.setImageBitmap(bitmap);}}).execute(path);return convertView;}class ViewHolder {private TextView tvSubject, tvSummary, tvChanged;private ImageView ivCover;}}// 加载图片的异步任务class ImageTask extends AsyncTask<String, Void, Bitmap> {private ImageCallback callback;private String path;public ImageTask(ImageCallback callback) {super();this.callback = callback;}@Overrideprotected Bitmap doInBackground(String... params) {Bitmap bitmap = null;try {URL url = new URL(params[0]);HttpURLConnection conn = (HttpURLConnection) url.openConnection();bitmap = BitmapFactory.decodeStream(conn.getInputStream());} catch (Exception e) {e.printStackTrace();}return bitmap;}@Overrideprotected void onPostExecute(Bitmap result) {super.onPostExecute(result);if (result != null) {callback.send(result, path);}}}public interface ImageCallback {void send(Bitmap bitmap, String path);}}

四、接下来是把我们要解析的数据封装成了一个类Data

package com.example.text_01_bean;public class Data {private String subject;private String summary;private String changed;private String cover;public String getSubject() {return subject;}public void setSubject(String subject) {this.subject = subject;}public String getSummary() {return summary;}public void setSummary(String summary) {this.summary = summary;}public String getChanged() {return changed;}public void setChanged(String changed) {this.changed = changed;}public String getCover() {return cover;}public void setCover(String cover) {this.cover = cover;}}

下面是把我们的网址解析为List<Data>集合的工具类HttpUtils：

package com.example.text_01_http;import java.io.BufferedReader;import java.io.IOException;import java.io.InputStreamReader;import java.net.HttpURLConnection;import java.net.URL;import java.util.ArrayList;import java.util.List;import org.json.JSONArray;import org.json.JSONException;import org.json.JSONObject;import com.example.text_01_bean.Data;import android.graphics.Bitmap;import android.graphics.BitmapFactory;public class HttpUtils {// 得到Json字符串的方法public static String getJsonContent(String path) {String result = "";BufferedReader bufr = null;try {URL url = new URL(path);HttpURLConnection conn = (HttpURLConnection) url.openConnection();bufr = new BufferedReader(new InputStreamReader(conn.getInputStream()));String line = "";while ((line = bufr.readLine()) != null) {result += line;}} catch (Exception e) {e.printStackTrace();} finally {try {bufr.close();} catch (IOException e) {e.printStackTrace();}}return result;}// 得到List<Data>集合的方法public static List<Data> getList(String path) {List<Data> list = new ArrayList<Data>();String json = getJsonContent(path);try {JSONObject obj = new JSONObject(json);JSONArray arr = obj.getJSONObject("paramz").getJSONArray("feeds");for (int j = 0; j < arr.length(); j++) {JSONObject obj2 = arr.getJSONObject(j).getJSONObject("data");Data data = new Data();data.setSubject(obj2.getString("subject"));data.setSummary(obj2.getString("summary"));data.setChanged(obj2.getString("changed"));data.setCover("http://litchiapi.jstv.com"+ obj2.getString("cover"));list.add(data);}} catch (JSONException e) {e.printStackTrace();}return list;}}

好了，写了那么多，看一下运行结果吧：第一幅图是我们还没有得到数据时的显示