解析接口中的json串网络图片数据，实现效果为无限轮播图+小圆点

一.MainActivity.java  主页面

package com.month_02;
import android.content.Intent;
import android.os.AsyncTask;
import android.os.Handler;
import android.os.Message;
import android.support.v4.view.ViewPager;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.ImageView;
import android.widget.LinearLayout;
import com.adapter.MyPagerAdapter;
import com.bean.DishBean;
import com.google.gson.Gson;
import com.util.StringUtil;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.ArrayList;
import java.util.List;

public class MainActivity extends AppCompatActivity {
private List<DishBean.ResultBean.DataBean>  list = new ArrayList<>();
private MyPagerAdapter pagerAdapter;
private ViewPager main_viewPager;
private LinearLayout linearLayout;
private List<ImageView> images;
private Handler handler = new Handler() {
@Override
public void handleMessage(Message msg) {
if (msg.what == 0) {
int currentItem = main_viewPager.getCurrentItem();
main_viewPager.setCurrentItem(currentItem + 1);

//延时发送消息
handler.sendEmptyMessageDelayed(0, 2888);
}
}
};

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

linearLayout = (LinearLayout) findViewById(R.id.lineLayout);
main_viewPager = (ViewPager) findViewById(R.id.main_ViewPager);

//异步任务加载数据
task();

//延时发送空消息，设置图片的位置
main_viewPager.setCurrentItem(list.size() % 10000);
handler.sendEmptyMessageDelayed(0, 2888);
}

private void task() {
AsyncTask<String,String,String> task = new AsyncTask<String,String,String>() {

@Override
protected String doInBackground(String... strings) {
try {
//路径
String path="http://apis.juhe.cn/cook/query?key=ab2da3f9abd4556dfd68086a66ffc4a8&menu=%E8%A5%BF%E7%BA%A2%E6%9F%BF&rn=10&pn=3";
//连接设置网络
URL url = new URL(path);
HttpURLConnection connection = (HttpURLConnection) url.openConnection();
connection.setRequestMethod("GET");
connection.setConnectTimeout(5000);
connection.setReadTimeout(5000);
//响应数据
int responseCode = connection.getResponseCode();
if (responseCode == 200){
InputStream inputStream = connection.getInputStream();
String json = StringUtil.streamToString(inputStream,"utf-8");
return json;
}
} catch (Exception e) {
e.printStackTrace();
}
return null;
}

@Override
protected void onPostExecute(String result) {
DishBean dishBean = new Gson().fromJson(result, DishBean.class);

//调用设置适配器的方法，设置展示数据
if (dishBean != null) {
list.addAll(dishBean.getResult().getData());

// 初始化小圆点的方法
initCircle();

//设置适配器
setAdapter();
}
}
};
task.execute();
}

private void initCircle() {
//首先需要一个集合记录这些小圆点的图片,,,,当页面切换的时候,可以从集合中取出imageView进行显示图片的设置
images = new ArrayList<>();
//再清除线性布局中的view视图
linearLayout.removeAllViews();

//遍历集合数据对应的圆点
for(int i = 0;i<list.size();i++) {
//先初始化一个ImageView视图
ImageView imageView = new ImageView(MainActivity.this);

//再设置小圆点刚开始的颜色
if (i == 0){
imageView.setImageResource(R.drawable.shape_selected);
}else {
imageView.setImageResource(R.drawable.shape_select_no);
}

//把设置好的视图添加到集合中
images.add(imageView);

//再把视图添加到线性布局中显示
LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT, LinearLayout.LayoutParams.WRAP_CONTENT);
params.setMargins(12,0,12,0);
linearLayout.addView(imageView,params);
}
}

private void setAdapter() {
//设置无限轮播图的适配器
if (pagerAdapter == null) {
pagerAdapter = new MyPagerAdapter(MainActivity.this, list);
main_viewPager.setAdapter(pagerAdapter);

//viewPager页面改变的监听事件
main_viewPager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {
@Override
public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
}

@Override
public void onPageSelected(int position) {
//设置小圆点的选中颜色
for (int i = 0; i < images.size(); i++) {
if (i == position%images.size()){
images.get(i).setImageResource(R.drawable.shape_selected);
}else {
images.get(i).setImageResource(R.drawable.shape_select_no);
}
}
}

@Override
public void onPageScrollStateChanged(int state) {
}
});
}else {
pagerAdapter.notifyDataSetChanged();
}
}
}

二.实现轮播图的适配器：  MyPagerAdapter.java（自定义bean类）

package com.adapter;import android.content.Context;import android.support.v4.view.PagerAdapter;import android.view.View;import android.view.ViewGroup;import android.widget.ImageView;import com.bean.DishBean;import com.nostra13.universalimageloader.core.ImageLoader;import java.util.List;public class MyPagerAdapter extends PagerAdapter{private Context context;private List<DishBean.ResultBean.DataBean> list;public MyPagerAdapter(Context context, List<DishBean.ResultBean.DataBean> list) {this.context = context;this.list = list;}@Overridepublic int getCount() {return Integer.MAX_VALUE;}@Overridepublic boolean isViewFromObject(View view, Object object) {return view == object;}@Overridepublic Object instantiateItem(ViewGroup container, int position) {//设置无限轮播图视图ImageView imageView = new ImageView(context);imageView.setScaleType(ImageView.ScaleType.FIT_XY);ImageLoader.getInstance().displayImage(list.get(position%list.size()).getSteps().get(0).getImg(),imageView);container.addView(imageView);return imageView;}@Overridepublic void destroyItem(ViewGroup container, int position, Object object) {container.removeView((View) object);}}

三.使用的工具类：

1.  应用全局化配置Application类：BaseApplication.java

package com.util;import android.app.Application;//全局初始化Application类public class BaseApplication extends Application {@Overridepublic void onCreate() {super.onCreate();//配置imageLoaderImageLoaderUtil.init(this);}}

2.  配置ImageLoader类：ImageLoaderUtil.java

package com.util;import android.content.Context;import android.graphics.Bitmap;import com.month_02.R;import com.nostra13.universalimageloader.cache.disc.impl.UnlimitedDiscCache;import com.nostra13.universalimageloader.cache.disc.naming.HashCodeFileNameGenerator;import com.nostra13.universalimageloader.cache.memory.impl.LruMemoryCache;import com.nostra13.universalimageloader.core.DisplayImageOptions;import com.nostra13.universalimageloader.core.ImageLoader;import com.nostra13.universalimageloader.core.ImageLoaderConfiguration;import com.nostra13.universalimageloader.core.assist.ImageScaleType;import com.nostra13.universalimageloader.core.assist.QueueProcessingType;import com.nostra13.universalimageloader.core.decode.BaseImageDecoder;import com.nostra13.universalimageloader.core.display.RoundedBitmapDisplayer;import com.nostra13.universalimageloader.core.display.SimpleBitmapDisplayer;import com.nostra13.universalimageloader.core.download.BaseImageDownloader;import com.nostra13.universalimageloader.utils.StorageUtils;import java.io.File;public class ImageLoaderUtil {/*** 初始化imageLoader* @param context*/public static void init(Context context) {//1.获取配置config对象File cacheDir = StorageUtils.getCacheDirectory(context);  //缓存文件夹路径ImageLoaderConfiguration config = new ImageLoaderConfiguration.Builder(context).threadPoolSize(3) // default  线程池内加载的数量.threadPriority(Thread.NORM_PRIORITY - 2) // default 设置当前线程的优先级.tasksProcessingOrder(QueueProcessingType.FIFO) // default.denyCacheImageMultipleSizesInMemory().memoryCache(new LruMemoryCache(2 * 1024 * 1024)) //可以通过自己的内存缓存实现.memoryCacheSize(2 * 1024 * 1024)  // 内存缓存的最大值.memoryCacheSizePercentage(13) // default.diskCache(new UnlimitedDiscCache(cacheDir)) // default 可以自定义缓存路径.diskCacheSize(50 * 1024 * 1024) // 50 Mb sd卡(本地)缓存的最大值.diskCacheFileCount(100)  // 可以缓存的文件数量// default为使用HASHCODE对UIL进行加密命名， 还可以用MD5(new Md5FileNameGenerator())加密.diskCacheFileNameGenerator(new HashCodeFileNameGenerator()).imageDownloader(new BaseImageDownloader(context)) // default.imageDecoder(new BaseImageDecoder(true)) // default.defaultDisplayImageOptions(DisplayImageOptions.createSimple()) // default.writeDebugLogs() // 打印debug log.build(); //开始构建//2.初始化配置...ImageLoader.getInstance()图片加载器的对象,单例模式ImageLoader.getInstance().init(config);}/*** imageLoader加载图片的默认选项* @return*/public static DisplayImageOptions getDefaultOption(){DisplayImageOptions options = new DisplayImageOptions.Builder().showImageOnLoading(R.drawable.micpic) // 设置图片下载期间显示的默认图片.showImageForEmptyUri(R.drawable.micpic) // 设置图片Uri为空或是错误的时候显示的图片.showImageOnFail(R.drawable.micpic) // 设置图片加载或解码过程中发生错误显示的图片.resetViewBeforeLoading(true)  // default 设置图片在加载前是否重置、复位.delayBeforeLoading(1000)  // 下载前的延迟时间.cacheInMemory(true) // default  设置下载的图片是否缓存在内存中.cacheOnDisk(true) // default  设置下载的图片是否缓存在SD卡中.considerExifParams(true) // default.imageScaleType(ImageScaleType.IN_SAMPLE_POWER_OF_2) // default 设置图片以如何的编码方式显示.bitmapConfig(Bitmap.Config.RGB_565) // default 设置图片的解码类型.displayer(new SimpleBitmapDisplayer()) // default  还可以设置圆角图片new RoundedBitmapDisplayer(20).build();return options;}/*** imageLoader加载圆角图片....指定圆角的大小* @return*/public static DisplayImageOptions getRoundedOption(int corner){DisplayImageOptions options = new DisplayImageOptions.Builder().showImageOnLoading(R.drawable.micpic) // 设置图片下载期间显示的图片.showImageForEmptyUri(R.drawable.micpic) // 设置图片Uri为空或是错误的时候显示的图片.showImageOnFail(R.drawable.micpic) // 设置图片加载或解码过程中发生错误显示的图片.resetViewBeforeLoading(true)  // default 设置图片在加载前是否重置、复位.delayBeforeLoading(1000)  // 下载前的延迟时间.cacheInMemory(true) // default  设置下载的图片是否缓存在内存中.cacheOnDisk(true) // default  设置下载的图片是否缓存在SD卡中.considerExifParams(true) // default.imageScaleType(ImageScaleType.IN_SAMPLE_POWER_OF_2) // default 设置图片以如何的编码方式显示.bitmapConfig(Bitmap.Config.RGB_565) // default 设置图片的解码类型.displayer(new RoundedBitmapDisplayer(corner)) // default  还可以设置圆角图片new RoundedBitmapDisplayer(20).build();return options;}}

3. 解析json串数据： StringUtil.java

package com.util;import java.io.BufferedReader;import java.io.InputStream;import java.io.InputStreamReader;public class StringUtil {public static String streamToString(InputStream inputStream, String charset) {try {InputStreamReader inputStreamReader = new InputStreamReader(inputStream,charset);BufferedReader bufferedReader = new BufferedReader(inputStreamReader);String s = null;StringBuilder builder = new StringBuilder();while ((s = bufferedReader.readLine()) != null){builder.append(s);}bufferedReader.close();return builder.toString();} catch (Exception e) {e.printStackTrace();}return  null;}}

四. 自定义布局文件：

1. drawable文件夹下设置小圆点的布局文件（1）shape_selected.xml<?xml version="1.0" encoding="utf-8"?><shape xmlns:android="http://schemas.android.com/apk/res/android"><solid android:color="#00b7ff"></solid><corners android:radius="8dp"></corners><size android:width="8dp" android:height="8dp"></size></shape>（2）shape_select_no.xml<?xml version="1.0" encoding="utf-8"?><shape xmlns:android="http://schemas.android.com/apk/res/android"><solid android:color="#dfdfdf"></solid><corners android:radius="8dp"></corners><size android:width="8dp" android:height="8dp"></size></shape>2. layout文件夹下的布局文件：activity_main.xml<?xml version="1.0" encoding="utf-8"?><RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"android:layout_width="match_parent"android:layout_height="match_parent" ><android.support.v4.view.ViewPagerandroid:id="@+id/main_ViewPager"android:layout_width="match_parent"android:layout_height="match_parent"></android.support.v4.view.ViewPager><LinearLayoutandroid:id="@+id/lineLayout"android:orientation="horizontal"android:gravity="center_horizontal"android:layout_width="match_parent"android:layout_height="wrap_content"android:layout_marginBottom="28dp"android:layout_alignBottom="@+id/main_ViewPager" ></LinearLayout></RelativeLayout>如想实现PullToRefresh，Fragment数据多条目，侧滑菜单栏，TabLayout，点击下面的连接：http://blog.csdn.net/IT666DHW/article/details/78030821