android - 从 ftp 服务器上传或下载 : Android Client

Question

我正在开发 android 项目来测试上传或下载文件的 FTP 功能。这是我基于 this 的第一个尝试代码教程:

public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    try {
        SimpleFTP ftp = new SimpleFTP();

        // Connect to an FTP server on port 21.
        ftp.connect("ftp.olympe-network.com", 21, "username", "password");


        // Set binary mode.
        ftp.bin();

        // Change to a new working directory on the FTP server.
        ftp.cwd("web");

        // Upload some files.
        ftp.stor(new File("shirt.jpg"));
        //ftp.stor(new File("comicbot-latest.png"));

        // You can also upload from an InputStream, e.g.
        ftp.stor(new FileInputStream(new File("shirt.jpg")), "shirt.jpg");
        /*ftp.stor(someSocket.getInputStream(), "blah.dat");
        */

        // Quit from the FTP server.
        ftp.disconnect();
    }
    catch (IOException e) {
        // Jibble.
    }
}

我的 shirt.jpg 文件存储在主项目文件夹中。我使用的是模拟器而不是物理设备。我的日志中没有错误，但文件未上传。

然后，我换了另一种方法:

private void loadLogs() {
    //radBtn.addView(null);
    new processTask().execute();
}
private class processTask extends AsyncTask<String, Void, Void>{
    private ProgressDialog Dialog = new ProgressDialog(activitiMain.this);
     private TextView log; 
     private  Spinner s;
    protected void onPreExecute() {
        Dialog.setMessage("Loading...");
        Dialog.show();
    }
    @Override
    protected Void doInBackground(String... arg0) {
        FTPClient client = new FTPClient();
        try {
        SharedPreferences myPref = PreferenceManager.getDefaultSharedPreferences(getBaseContext());
        String ipaddr = myPref.getString("etServer", "");
        String port= myPref.getString("port", "21");
        String logFile= myPref.getString("logfname", "error_log");
        String filePath= myPref.getString("path", "/public_html");
        String uname= myPref.getString("uname", "");
        String pass= myPref.getString("pass", "");
        client.connect(ipaddr,21);
        client.enterLocalPassiveMode();
        boolean login = client.login(uname, pass);
        client.changeWorkingDirectory(filePath);
        System.out.println(client.printWorkingDirectory());

        BufferedReader reader = null;
        String line = null;
        sv = new ScrollView(activitiMain.this);                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
        sv.setLayoutParams(LP_FF);
        LinearLayout loglay  =  new LinearLayout(activitiMain.this);
        loglay.setOrientation( LinearLayout.VERTICAL );  //FTPFile[] ftpFiles = client.listFiles();
        FTPFile[] ftpFiles = client.listFiles();
        ArrayList<String> name = new ArrayList<String>();                              
        ArrayAdapter <CharSequence> adapter =new ArrayAdapter <CharSequence> (getBaseContext(), android.R.layout.simple_spinner_item );
            adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);

             adapter.add("Select File");*/      
            //s = new (Spinner)findViewById(R.id.Spinner01);
            s = new Spinner(activitiMain.this);
            for (int i = 0; i < ftpFiles.length; i++) { 
                String fname =ftpFiles[i].getName();
                Log.i("FTP", "File " +i +" : "+fname);
                       name.add(fname);
                        long length = ftpFiles[i].getSize();
                        //adapter2.add(ftpFiles[i].getName());
                        //String readableLength = FileUtils.byteCountToDisplaySize( length );
                        ///System.out.println( name + ":\t\t" + readableLength );  
                    }
            //String [] strArray =null;
            //strArray.toArray(name);
            String [] files = name.toArray(new String[name.size()]);
            @SuppressWarnings("unchecked")
            ArrayAdapter<Object> adapter2 = new ArrayAdapter<Object>(getApplicationContext(), android.R.layout.simple_spinner_item,files);  
             adapter2.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);  
             s.setAdapter(adapter2);  
             loglay.addView(s);

         Log.i("Files", ftpFiles.toString());
            for (FTPFile ftpFile : ftpFiles) {
                String fileName = ftpFile.getName(); 
                if (fileName.equals(logFile)){
                     try {
                         InputStream stream = client.retrieveFileStream(fileName);                             
                         reader = new BufferedReader(new InputStreamReader(stream, "UTF-8"));
                         //line = reader.readLine();


                         while ((line = reader.readLine())!= null && line.trim().length()>0) {
                                //System.out.println(line);
                             log = new TextView(activitiMain.this);
                                String trail = line; 
                                log.setTextColor(Color.GREEN);                                                                                                                                                                                                                                                                                                                                 
                                log.setPadding(10, 5, 0, 5);
                                log.setText(trail);                                                                                                                                                                                                                                                                                                                                   
                                loglay.addView(log);    
                            }
                         sv.addView(loglay);
                     } finally {
                         if (reader != null) try { reader.close(); } catch (IOException logOrIgnore) {}
                     }
                }
            }
               client.logout();


        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                client.disconnect();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        return null;
    }
    protected void onPostExecute(Void unused) {
        Dialog.dismiss();
        setContentView(sv);
        }

在我的首选项屏幕中，我指定了 ftp 服务器参数，但我的 logcat 中也出现错误:

    05-27 18:36:38.237: ERROR/AndroidRuntime(585): FATAL EXCEPTION: main
05-27 18:36:38.237: ERROR/AndroidRuntime(585): java.lang.NullPointerException
05-27 18:36:38.237: ERROR/AndroidRuntime(585):     at android.view.ViewGroup.addViewInner(ViewGroup.java:1969)
05-27 18:36:38.237: ERROR/AndroidRuntime(585):     at android.view.ViewGroup.addView(ViewGroup.java:1865)
05-27 18:36:38.237: ERROR/AndroidRuntime(585):     at android.view.ViewGroup.addView(ViewGroup.java:1845)
05-27 18:36:38.237: ERROR/AndroidRuntime(585):     at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:217)
05-27 18:36:38.237: ERROR/AndroidRuntime(585):     at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:207)
05-27 18:36:38.237: ERROR/AndroidRuntime(585):     at android.app.Activity.setContentView(Activity.java:1658)
05-27 18:36:38.237: ERROR/AndroidRuntime(585):     at com.sam.remote.activitiMain$processTask.onPostExecute(activitiMain.java:160)
05-27 18:36:38.237: ERROR/AndroidRuntime(585):     at com.sam.remote.activitiMain$processTask.onPostExecute(activitiMain.java:1)
05-27 18:36:38.237: ERROR/AndroidRuntime(585):     at android.os.AsyncTask.finish(AsyncTask.java:417)
05-27 18:36:38.237: ERROR/AndroidRuntime(585):     at android.os.AsyncTask.access$300(AsyncTask.java:127)
05-27 18:36:38.237: ERROR/AndroidRuntime(585):     at android.os.AsyncTask$InternalHandler.handleMessage(AsyncTask.java:429)
05-27 18:36:38.237: ERROR/AndroidRuntime(585):     at android.os.Handler.dispatchMessage(Handler.java:99)
05-27 18:36:38.237: ERROR/AndroidRuntime(585):     at android.os.Looper.loop(Looper.java:123)
05-27 18:36:38.237: ERROR/AndroidRuntime(585):     at android.app.ActivityThread.main(ActivityThread.java:4627)
05-27 18:36:38.237: ERROR/AndroidRuntime(585):     at java.lang.reflect.Method.invokeNative(Native Method)
05-27 18:36:38.237: ERROR/AndroidRuntime(585):     at java.lang.reflect.Method.invoke(Method.java:521)
05-27 18:36:38.237: ERROR/AndroidRuntime(585):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
05-27 18:36:38.237: ERROR/AndroidRuntime(585):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
05-27 18:36:38.237: ERROR/AndroidRuntime(585):     at dalvik.system.NativeStart.main(Native Method)

Answer 1

当你说你的文件 shirt.jpg 存储在你的主项目文件夹中时，看看你在这里的第一次尝试我不认为你的代码会发现一旦部署到设备，你可能必须手动存储它设备上的文件，如下所述:

http://developer.android.com/guide/topics/data/data-storage.html#filesInternal

或者您可以先将 shirt.jpg 文件(通过 ADP)上传到您的应用程序共享目录，如下所述:

http://developer.android.com/guide/topics/data/data-storage.html#filesExternal

然后尝试读取它并通过 FTP 传输它。

哦，是的，还有我在 Android 上保存文件然后通过电子邮件发送它们的经验，请使用实际设备进行测试，因为模拟器不会为您提供所需的网络连接。