Android解析XML文件

XML文件和获取XML值

XML文件样例

<?xml version="1.0" encoding="utf-8"?>
<citys>
   <city  name="CAF">中非</city>
   <city  name="TCD">乍得</city>
   <city  name="CHL">智利</city>
   <city  name="CHN">中国</city>
   <city  name="HKG">香港</city>
   <city  name="MAC">澳门</city>
   <city  name="TWN">*</city>
</citys>

获取XML内容

private String getNationality(String str){
    XmlResourceParser xpr = getResources().getXml(R.xml.nationality);// 找到xml文件
    try {
        // 循环解析
        while (xpr.getEventType() != XmlResourceParser.END_DOCUMENT) {
            if (xpr.getEventType() == XmlResourceParser.START_TAG) {
                String name = xpr.getName(); //获取标签名
                if (name.equals("city")) {
                    if(str.equals(xpr.getAttributeValue(null, "name"))){//获取标签里的值
                        return xpr.nextText();//获取标签的内容
                    }
                }
            }
            try {
                xpr.next();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    } catch (XmlPullParserException | IOException e) {
        e.printStackTrace();
    }
    return "null";
}

升级APK

发送请求获取输入流

Thread thread = new Thread() {
    @Override
    public void run() {
        super.run();
        //XML存放在ftp服务器的地址
        String path = FileUtils.getDevice_address()+"News.XML";
        try {
            URL url = new URL(path);
            HttpURLConnection conn = (HttpURLConnection) url
                    .openConnection();
            conn.setRequestMethod("GET");
            conn.setConnectTimeout(5000);
            conn.setReadTimeout(5000);
            //发送http GET请求，获取相应码
            if (conn.getResponseCode() == 200) {
                InputStream is = conn.getInputStream();
                //使用pull解析器，开始解析这个流
                parseNewsXml(is);
            }
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
};
thread.start();    

解析XML文件

private void parseNewsXml(InputStream is) {
    XmlPullParser xp = Xml.newPullParser();
    try {
        xp.setInput(is, "utf-8");
        //对节点的事件类型进行判断，就可以知道当前节点是什么节点
        int type = xp.getEventType();
        News news = null;
        while (type != XmlPullParser.END_DOCUMENT) {
            switch (type) {
                case XmlPullParser.START_TAG:
                    if ("newslist".equals(xp.getName())) {
                        newsList = new ArrayList<>();
                        break;
                    } else if ("news".equals(xp.getName())) {
                        news = new News();
                        break;
                    } else if ("name".equals(xp.getName())) {
                        String name = xp.nextText();
                        news.setName(name);
                        break;
                    } else if ("code".equals(xp.getName())) {
                        String code = xp.nextText();
                        news.setCode(code);
                        break;
                    }
                case XmlPullParser.END_TAG:
                    if ("news".equals(xp.getName())) {
                        newsList.add(news);
                    }
                    break;
                 default:
                    break;
            }
            //解析完当前节点后，把指针移动至下一个节点，直至节点完毕，并返回它的事件类型
            type = xp.next();
        }
        // 发消息
        handler.sendEmptyMessage(1);
    } catch (Exception e) {
        e.printStackTrace();
    }
}

开始下载

//获取下载管理器
DownloadManager manager =(DownloadManager)mContext.getSystemService(mContext.DOWNLOAD_SERVICE);

handler = new Handler() {
    @Override
    public void handleMessage(Message msg) {
        super.handleMessage(msg);
        News news = newsList.get(0);
        Log.i("aii", "XML: "+news.getCode()+"，apk:"+getPackageInfo(mContext));
        if(Integer.valueOf(news.getCode())>Integer.valueOf(getPackageInfo(mContext))){
           if(dowmCliek) {
                //开启进度条线程
                isRun = true;
                dowmCliek = false;
                //更新APK前删除原来的安装包
                DownLoadApk.fileDelete(path + "/" + mAPK);
                //创建下载请求
                DownloadManager.Request down = new DownloadManager.Request(
                        Uri.parse(mWebsite));
                //设置允许使用的网络类型，这里是移动网络和wifi都可以
                down.setAllowedNetworkTypes(DownloadManager.Request.NETWORK_MOBILE | DownloadManager.Request.NETWORK_WIFI);
                //禁止发出通知，既后台下载
                down.setShowRunningNotification(true);
                //不显示下载界面
                down.setVisibleInDownloadsUi(true);
                //标题
                down.setDestinationInExternalFilesDir(mContext, null, "XXX升级中...");
                //将下载请求放入队列，返回下载id
                downId = manager.enqueue(down);
            }else{
                Toast.makeText(mContext,"升级中...",Toast.LENGTH_SHORT).show();
            }
        }else{
                Toast.makeText(mContext,"已是最新版本无需升级...",Toast.LENGTH_SHORT).show();
        }
    }
};

跟踪下载进度

//定时任务
ScheduledExecutorService scheduledExecutorService = Executors.newScheduledThreadPool(1);
scheduledExecutorService.scheduleAtFixedRate(new Runnable() {
            @Override
            public void run() {
                if(isRun) {
                    Message msg = mHandler.obtainMessage();
                    msg.what = 1;
                    mHandler.sendMessage(msg);
                }
            }
        }, 0, 100, TimeUnit.MILLISECONDS);//延迟0，间隔100，单位毫秒

private Handler mHandler = new Handler(new Handler.Callback() {
    @Override
    public boolean handleMessage(Message msg) {
        switch (msg.what) {
            case 1:
                //android下载管理器
                DownloadManager.Query query = new DownloadManager.Query().setFilterById(downId);
                Cursor cursor = manager.query(query);
                if (cursor != null && cursor.moveToFirst()) {
                    //此处直接查询文件大小
                    long downSize = cursor.getLong(cursor.getColumnIndex(
                            DownloadManager.COLUMN_TOTAL_SIZE_BYTES));
                    //获取文件下载总大小
                    fileTotalSize =cursor.getLong(cursor.getColumnIndex(
                            DownloadManager.COLUMN_BYTES_DOWNLOADED_SO_FAR));
                    cursor.close();

                    Log.w("打印", "总大小" + downSize);
                    Log.w("打印", "下载进度 " + fileTotalSize);
                    if (fileTotalSize>0) {
                        NumberFormat numberFormat = NumberFormat.getInstance();
                        numberFormat.setMaximumFractionDigits(2);
                        String result = numberFormat.format((float)fileTotalSize/(float)downSize*100);
                        Log.w("打印", "downloaded size: " + result+"%");
                        downBtn.setText(result+"%");
                    }
                    //下载完毕
                    if(fileTotalSize==downSize) {
                        isRun = false;
                        downBtn.setText("点击升级");
                    }
                }
        }
        return true;
    }
});

下载完毕启动安装

DownloadCompleteReceiver receiver = new DownloadCompleteReceiver();

//下载完成后的广播
class DownloadCompleteReceiver extends BroadcastReceiver {
    @Override
    public void onReceive(Context context, Intent intent) {
        if(intent.getAction().equals(DownloadManager.ACTION_DOWNLOAD_COMPLETE)){
            long downId = intent.getLongExtra(DownloadManager.EXTRA_DOWNLOAD_ID, -1);
            if(downId!=-1) {
                //启动安装
                DownLoadApk.DownId(context,downId);
                dowmCliek=true;
            }
        }else{
            Toast.makeText(context, intent.getAction()+"下载失败", Toast.LENGTH_SHORT).show();
        }
    }
}

//启动下载完成广播
mContext.registerReceiver(receiver, new IntentFilter(DownloadManager.ACTION_DOWNLOAD_COMPLETE));

安装APK

public class DownLoadApk {
    public static SharedPreferences sharedPrederences = null;
    //启动安装界面
    public static void DownId(Context context, long downId){
        DownloadManager mDownloadManager = (DownloadManager) context.getSystemService(Context.DOWNLOAD_SERVICE);
        Uri downloadUri = mDownloadManager.getUriForDownloadedFile(downId);
        startInstall(context, downloadUri);
   }
    /**
     * 跳转到安装界面
     * @param context 作用域
     * @param uri 包名
     */
    private static void startInstall(Context context, Uri uri) {
        Intent install = new Intent(Intent.ACTION_VIEW);
        install.setDataAndType(uri, "application/vnd.android.package-archive");
        install.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
        context.startActivity(install);
    }
    //删除文件
    public static boolean fileDelete(String filePath) {
        File file = new File(filePath);
        if (file.exists() == false) {
            return false;
        }
        return file.delete();
    }

获取项目包名

private static String getPackageInfo(Context context) {
    PackageInfo pi = null;
    try {
        PackageManager pm = context.getPackageManager();
        pi = pm.getPackageInfo(context.getPackageName(),
                PackageManager.GET_CONFIGURATIONS);
        return pi.versionCode+"";
    } catch (Exception e) {
        e.printStackTrace();
    }
    return null;
}