图片框架 三重更新 联网解析json设置默认图片以及图片圆角弧度 储存到sd卡

import android.graphics.Bitmap;
import com.ljn.myapplication.R;
import com.nostra13.universalimageloader.core.DisplayImageOptions;
import com.nostra13.universalimageloader.core.assist.ImageScaleType;
import com.nostra13.universalimageloader.core.display.RoundedBitmapDisplayer;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;

public class Utils {
public static DisplayImageOptions getDisplayImageOption() {
DisplayImageOptions options = new DisplayImageOptions.Builder()
.showImageOnLoading(R.mipmap.ic_launcher) //设置图片在下载期间显示的图片
.showImageForEmptyUri(R.mipmap.ic_launcher)//设置图片Uri为空或是错误的时候显示的图片
.showImageOnFail(R.mipmap.ic_launcher)  //设置图片加载/解码过程中错误时候显示的图片
.cacheInMemory(true)//设置下载的图片是否缓存在内存中
.cacheOnDisk(true)
.considerExifParams(true)  //是否考虑JPEG图像EXIF参数（旋转，翻转）
.imageScaleType(ImageScaleType.EXACTLY_STRETCHED)//设置图片以如何的编码方式显示
.bitmapConfig(Bitmap.Config.RGB_565)//设置图片的解码类型//
.displayer(new RoundedBitmapDisplayer(30))//是否设置为圆角，弧度为多少
//                .displayer(new FadeInBitmapDisplayer(100))//是否图片加载好后渐入的动画时间
.build();//构建完成
return options;
}

public static String getNetString(String str){
try {
URL url=new URL(str);
HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();
int responseCode = urlConnection.getResponseCode();
if (responseCode==200){
InputStream is = urlConnection.getInputStream();
BufferedReader br=new BufferedReader(new InputStreamReader(is));
StringBuilder sb=new StringBuilder();
String line=null;
while ((line=br.readLine())!=null){
sb.append(line);
}
return sb.toString();
}
} catch (MalformedURLException e) {
e.printStackTrace();
}catch (IOException e) {
e.printStackTrace();
}
return null;
}

}

import android.app.Application;
import android.os.Environment;

import com.nostra13.universalimageloader.cache.disc.impl.UnlimitedDiskCache;
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.QueueProcessingType;

import java.io.File;

/**
* Created by HP on 2017/11/8.
*/

public class MApp extends Application{
File cacheFile= new File(Environment.getExternalStorageDirectory()+"/"+"imgages");

@Override
public void onCreate() {
super.onCreate();
//初始化组件,链式开发思想,整个框架的参数初始化配置
ImageLoaderConfiguration configuration = new ImageLoaderConfiguration.Builder(this)
.memoryCacheExtraOptions(480, 800) // default = device screen dimensions 内存缓存文件的最大长宽
.diskCacheExtraOptions(480, 800, null)  // 本地缓存的详细信息(缓存的最大长宽)，最好不要设置这个
.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
.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
.diskCache(new UnlimitedDiskCache(cacheFile))//自定义缓存目录
// 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())
.defaultDisplayImageOptions(DisplayImageOptions.createSimple()) // default
.writeDebugLogs() // 打印debug log
.build();

ImageLoader.getInstance().init(configuration);

}
}

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.ImageView;
import android.widget.ListView;

import com.ljn.myapplication.bean.TextBean;
import com.ljn.myapplication.utils.Utils;
import com.nostra13.universalimageloader.core.ImageLoader;

import android.os.AsyncTask;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.graphics.Bitmap;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
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.google.gson.Gson;

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

public class MainActivity extends AppCompatActivity {
private ListView lv;
// ImagesUtils imagUtils;
private String NetString="https://api.tianapi.com/wxnew/?key=8d6e3228d25298f13af4fc40ce6c9679&num=10";
private List<TextBean.NewslistBean> list=new ArrayList<TextBean.NewslistBean>();
private MyAdapter adapter;
private ImageLoader instance;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// imagUtils = new ImagesUtils(this,handler);
instance = ImageLoader.getInstance();
lv = (ListView) findViewById(R.id.lv);
new MyAsyncTask().execute(NetString);
adapter = new MyAdapter();
lv.setAdapter(adapter);
}
//instance.displayImage(urlBitmap,iv, Utils.getDisplayImageOption());//如果listview配置图片用这一行
private class MyAsyncTask extends AsyncTask<String,Void,String> {
@Override
protected String doInBackground(String... strings) {
return Utils.getNetString(strings[0]);
}

@Override
protected void onPostExecute(String s) {
super.onPostExecute(s);
Gson gson=new Gson();
TextBean json = gson.fromJson(s, TextBean.class);
List<TextBean.NewslistBean> newslist = json.getNewslist();
list.addAll(newslist);
adapter.notifyDataSetChanged();
}
}

private class MyAdapter extends BaseAdapter {

private ViewHolder vh;
private TextView ctime;
private TextView title;
private TextView description;
private ImageView img;

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

@Override
public Object getItem(int i) {
return null;
}

@Override
public long getItemId(int i) {
return 0;
}

@Override
public View getView(int i, View view, ViewGroup viewGroup) {
if (view==null){
vh = new ViewHolder();
view = View.inflate(MainActivity.this, R.layout.item, null);
view.setTag(vh);
}else{
vh = (ViewHolder) view.getTag();
}
vh.ctime = view.findViewById(R.id.item_ctime);
vh.title = view.findViewById(R.id.item_title);
vh.description = view.findViewById(R.id.item_description);
vh.img = view.findViewById(R.id.item_img);
vh.ctime.setText(list.get(i).getCtime());
vh.title.setText(list.get(i).getTitle());
vh.description.setText(list.get(i).getDescription());
instance.displayImage(list.get(i).getPicUrl(),vh.img, Utils.getDisplayImageOption());
return view;
}
}
class ViewHolder{
TextView ctime;
TextView title;
TextView description;
ImageView img;
}
}

在application中配置

android:name=".Mapp"

在build.grable下配置

compile 'com.nostra13.universalimageloader:universal-image-loader:1.9.5'

compile 'com.google.code.gson:gson:2.2.4'