自定义进度框

  首先如果要在程序中使用sdcard进行存储，我们必须要在AndroidManifset.xml文件进行下面的权限设置:  在AndroidManifest.xml中加入访问SDCard的权限如下:                  接着我们在使用SDcard进行读写的时候 会用到Environment类下面的几个静态方法     1: getDataDirectory()  获取到Androi中的data数据目录    2:getDownloadCacheDirectory()  获取到下载的缓存目录    3:getExternalStorageDirectory()  获取到外部存储的目录 一般指SDcard    4:getExternalStorageState() 获取外部设置的当前状态 一般指SDcard,          android系统中对于外部设置的状态，我们比较常用的应该是 MEDIA_MOUNTED（SDcard存在并且可以进行读写）  MEDIA_MOUNTED_READ_ONLY (SDcard存在，只可以进行读操作)  当然还有其他的一些状态，可以在文档中进行查找到     5:getRootDirectory()  获取到Android Root路径    6:isExternalStorageEmulated() 返回Boolean值判断外部设置是否有效    7:isExternalStorageRemovable()  返回Boolean值，判断外部设置是否可以移除  

【实例简介】仿电商后台管理系统源码 ：本系统采用的还layUI模板，基于ssm框架,功能趋于成熟，运行环境：mysql8.0，jdk8.0及以上，IDEA；我做此项目是用来实训结业答辩，项目可流畅运行，毕竟答辩时在领导面前总不能报错吧，若有意外，请亲检查版本，believe me!

用jfreechart实现动态曲线，有系统产生随机数，然后画出曲线，并能实时显示曲线

ListView下拉刷新,上拉加载更多

接收发送蓝牙消息、建立蓝牙通信连接、打印蓝牙消息

服务器端源码 看这里 https://github.com/simplehappy2600/simple-webrtc-video-chat

非常入门级的示例，适合新手

搞的地图最新1.4.2 Demo1.将MapApi.jar放到工程libs目录下；如果需要使用矢量地图，将libminimapv320.so放到libs下的armeabi目录下。2.在工程Build Path>Configure Build Path…>libraries 中选择“Add Externel JARs…”，选定MapApi.jar，点击OK，这样就可以将高德地图Android API 库文件引入。然后在工程Build Path>Configure Build Path…>Order and Export 中将引入的库文件MapApi.jar 选中（在Android2.2及以前的版本中必须选中，否则会有问题），点击OK。3.如果遇到问题，可以上问答社区http://api.amap.com/qa/。    

【核心代码】package com.gson;import java.io.File;import java.io.FileInputStream;import java.io.FileNotFoundException;import java.io.IOException;import java.lang.reflect.Field;import java.lang.reflect.Method;import java.util.Date;import java.util.Properties;import javax.servlet.Filter;import javax.servlet.FilterChain;import javax.servlet.FilterConfig;import javax.servlet.ServletException;import javax.servlet.ServletInputStream;import javax.servlet.ServletRequest;import javax.servlet.ServletResponse;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import org.apache.log4j.Logger;import com.gson.bean.Articles;import com.gson.bean.InMessage;import com.gson.bean.OutMessage;import com.gson.bean.TextOutMessage;import com.gson.inf.MessageProcessingHandler;import com.gson.util.Tools;import com.gson.util.XStreamFactory;import com.thoughtworks.xstream.XStream;/** * 请求拦截 * * @author GodSon * */public class WeChatFilter implements Filter { private final Logger logger = Logger.getLogger(WeChatFilter.class); private String _token; private String conf = "classPath:wechat.properties"; private String defaultHandler = "com.gson.inf.DefaultMessageProcessingHandlerImpl"; private Properties p; @Override public void destroy() { logger.info("WeChatFilter已经销毁"); } @Override public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws IOException, ServletException { HttpServletRequest request = (HttpServletRequest) req; HttpServletResponse response = (HttpServletResponse) res; Boolean isGet = request.getMethod().equals("GET"); String path = request.getServletPath(); String pathInfo = path.substring(path.lastIndexOf("/")); if (pathInfo == null) { response.getWriter().write("error"); } else { _token = pathInfo.substring(1); if (isGet) { doGet(request, response); } else { doPost(request, response); } } } private void doPost(HttpServletRequest request, HttpServletResponse response) throws IOException { response.setCharacterEncoding("UTF-8"); response.setContentType("text/xml"); OutMessage oms = new OutMessage(); ServletInputStream in = request.getInputStream(); // 转换微信post过来的xml内容 XStream xs = XStreamFactory.init(false); xs.alias("xml", InMessage.class); String xmlMsg = Tools.inputStream2String(in); logger.debug("输入消息:[" xmlMsg "]"); InMessage msg = (InMessage) xs.fromXML(xmlMsg); // 获取自定消息处理器，如果自定义处理器则使用默认处理器。 String handler = p.getProperty("MessageProcessingHandlerImpl"); if (handler == null) handler = defaultHandler; try { // 加载处理器 Class clazz = Class.forName(handler); MessageProcessingHandler processingHandler = (MessageProcessingHandler) clazz.newInstance(); // 取得消息类型 String type = msg.getMsgType(); Method mt = clazz.getMethod(type "TypeMsg", InMessage.class); oms = (OutMessage) mt.invoke(processingHandler, msg); if (oms == null) { oms = new TextOutMessage(); ((TextOutMessage) oms).setContent("系统错误!"); } setMsgInfo(oms,msg); } catch (Exception e) { logger.error(e); oms = new TextOutMessage(); ((TextOutMessage) oms).setContent("系统错误!"); try { setMsgInfo(oms,msg); } catch (Exception e1) { logger.error(e); } } // 把发送发送对象转换为xml输出 xs = XStreamFactory.init(true); xs.alias("xml", oms.getClass()); xs.alias("item", Articles.class); String xml = xs.toXML(oms); logger.debug("输出消息:[" xml "]"); response.getWriter().write(xml); } private void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException { String signature = request.getParameter("signature");// 微信加密签名 String timestamp = request.getParameter("timestamp");// 时间戳 String nonce = request.getParameter("nonce");// 随机数 String echostr = request.getParameter("echostr");// // 验证 if (Tools.checkSignature(_token, signature, timestamp, nonce)) { response.getWriter().write(echostr); } } private void setMsgInfo(OutMessage oms,InMessage msg) throws Exception { // 设置发送信息 Class outMsg = oms.getClass().getSuperclass(); Field CreateTime = outMsg.getDeclaredField("CreateTime"); Field ToUserName = outMsg.getDeclaredField("ToUserName"); Field FromUserName = outMsg.getDeclaredField("FromUserName"); ToUserName.setAccessible(true); CreateTime.setAccessible(true); FromUserName.setAccessible(true); CreateTime.set(oms, new Date().getTime()); ToUserName.set(oms, msg.getFromUserName()); FromUserName.set(oms, msg.getToUserName()); } /** * 启动的时候加载wechat.properties配置 可以在过滤器配置wechat.properties路径 */ @Override public void init(FilterConfig config) throws ServletException { String cf = config.getInitParameter("conf"); if (cf != null) { conf = cf; } String classPath = this.getClass().getResource("/").getPath().replaceAll("%20", " "); conf = conf.replace("classPath:", classPath); p = new Properties(); File pfile = new File(conf); if (pfile.exists()) { try { p.load(new FileInputStream(pfile)); } catch (FileNotFoundException e) { logger.error("未找到wechat.properties", e); } catch (IOException e) { logger.error("wechat.properties读取异常", e); } } logger.info("WeChatFilter已经启动！"); }}

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