廢話不說，上程式碼：

package com.jiyun.kaishu.Model;import android.content.Context;import android.util.Log;import java.io.File;import java.io.IOException;import java.util.concurrent.TimeUnit;import okhttp3.Cache;import okhttp3.Callback;import okhttp3.Interceptor;import okhttp3.OkHttpClient;import okhttp3.Request;import okhttp3.Response;/** * Created by lenovo on 2017/10/30. */public class Utils { private static Utils utils; private OkHttpClient okHttpClient; private Context context; private Utils(Context context) { this.context=context; getOk(); } private OkHttpClient getOk() { if (okHttpClient == null) { synchronized (OkHttpClient.class) { if (okHttpClient == null) { initOk(context); } } } return okHttpClient; } private void initOk(final Context context) { File httpCacheDirectory = new File("/sdcard", "cache_xx");// Cache cache = new Cache(this.getCacheDir(), 10240*1024); Cache cache = new Cache(httpCacheDirectory, 10240*1024*10); //10M OkHttpClient okHttpClient1 = new OkHttpClient(); okHttpClient = okHttpClient1.newBuilder() .addNetworkInterceptor(new Interceptor() { @Override public Response intercept(Chain chain) throws IOException { Log.d("MainActivity", "================進入攔截器"); Request request = chain.request(); Log.e("MainActivity", "新請求 =request==" + request.toString()); Response response = chain.proceed(request); //=========== Response response_build; if (NetUtil.checkNet(context)) { int maxAge = 60 * 60 * 24; // 有網路的時候從快取1天后失效 response_build = response.newBuilder() .removeHeader("Pragma") .removeHeader("Cache-Control") .header("Cache-Control", "public, max-age=" + maxAge) .build(); } else { int maxStale = 60 * 60 * 24 * 28; // // 無網路快取儲存四周 response_build = response.newBuilder() .removeHeader("Pragma") .removeHeader("Cache-Control") .header("Cache-Control", "public, only-if-cached, max-stale=" + maxStale) .build(); } return response_build; } }) .cache(cache) .connectTimeout(20, TimeUnit.SECONDS) .readTimeout(20, TimeUnit.SECONDS) .build(); } public static synchronized Utils getInstance(Context context){ if (utils==null){ utils=new Utils(context); } return utils; } public void sendGet(String url, Callback callback){ Request build = new Request.Builder().url(url).build(); okHttpClient.newCall(build).enqueue(callback); }}
package com.jiyun.kaishu.Model;import android.content.Context;import android.net.ConnectivityManager;import android.net.NetworkInfo;/** * Created by DELL on 2017-11-4. */public class NetUtil { //判斷當前手機聯網的渠道 public static boolean checkNet(Context context){ boolean wifiConnected = isWIFIConnected(context); boolean mobileConnected = isMOBILEConnected(context); boolean youxian = isYouXian(context); if(wifiConnected==false && mobileConnected== false&&youxian==false){ //如果都沒有連線，提示使用者當前沒有網路 return false; } return true; } private static boolean isYouXian(Context context) { ConnectivityManager manager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE); NetworkInfo networkInfo = manager.getNetworkInfo(ConnectivityManager.TYPE_ETHERNET); if (networkInfo != null && networkInfo.isConnected()) { return true; } return false; } public static boolean isMOBILEConnected(Context context) { ConnectivityManager manager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE); NetworkInfo networkInfo = manager.getNetworkInfo(ConnectivityManager.TYPE_MOBILE); if(networkInfo !=null && networkInfo.isConnected()){ return true; } return false; } private static boolean isWIFIConnected(Context context) { ConnectivityManager manager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE); NetworkInfo networkInfo = manager.getNetworkInfo(ConnectivityManager.TYPE_WIFI); if(networkInfo !=null && networkInfo.isConnected()){ return true; } return false; } // 新方法 public static boolean isConn(Context context){ boolean bisConnFlag=false; ConnectivityManager conManager = (ConnectivityManager)context.getSystemService(Context.CONNECTIVITY_SERVICE); NetworkInfo network = conManager.getActiveNetworkInfo(); if(network!=null){ bisConnFlag=conManager.getActiveNetworkInfo().isAvailable(); } return bisConnFlag; }}