为什么getDescription（）总是返回null，即使邮件有描述？

Question

我使用下面的代码：

public class tets extends Activity implements OnClickListener, 
android.view.View.OnClickListener { 
    /** Called when the activity is first created. */ 
    @Override 
    public void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.main); 
     Properties props = System.getProperties();  
     props.setProperty("mail.store.protocol", "imaps"); 
     Session session = Session.getDefaultInstance(props, null); 
     Store store = null; 
     Folder folder = null; 
     Message[] messages = null; 
     try { 
      store = session.getStore("imaps"); 
      store.connect("imap.gmail.com","xxx@gmail.com", "xxx"); 
      folder = store.getDefaultFolder(); 
      folder = folder.getFolder("INBOX"); 
      folder.open(Folder.READ_ONLY); 
      messages = folder.getMessages(); 
      Message Message[] = folder.getMessages(); 
      FetchProfile fp = new FetchProfile(); 
      folder.fetch(messages, fp);     
     } catch (MessagingException e) { 
      e.printStackTrace(); 
     } 
     //System.out.println("Message Count "+folder.getMessageCount()); 
     //System.out.println("New Message Count "+folder.getUnreadMessageCount()); 
     //FetchProfile fp = new FetchProfile(); 
     //fp.add(FetchProfile.Item.ENVELOPE); 
     //folder.fetch(messages, fp); 

     TableLayout table = (TableLayout) findViewById(R.id.TableLayout01); 


     for (int i = 0; i < messages.length; i++) 
     { 
      //System.out.println("From:"+ messages[i].getFrom()); 

      TableRow row = new TableRow(this); 
      // create a new TextView 
      TextView number = new TextView(this); 
      number.setOnClickListener(this); 
      TextView country = new TextView(this); 
      number.setOnClickListener(this); 
      // set the text to "text xx" 
      try{ 
       number.setText(messages[i].getDescription().toString()); 

      } 
      catch(MessagingException e) 
      { 
       e.printStackTrace(); 
      } 

      //country.setPadding(2, 1, 1, 1); 
      // add the TextView 
      row.addView(number); 
      row.addView(country); 
      // add the TableRow to the TableLayout 
      table.addView(row); 
      } try { 
          folder.close(true); 
          store.close(); 
         } catch (MessagingException e) { 
          e.printStackTrace(); 
         } 
    } 
    public void onClick(View v) { 
     Bundle bundle = new Bundle(); 
     bundle.putString("data", ((TextView) v).getText().toString()); 
     Intent newIntent = new Intent(this.getApplicationContext(), 
       Details.class); 
     newIntent.putExtras(bundle); 
     startActivity(newIntent); 
    } 
    public void onClick(DialogInterface dialog, int which) { 
     // TODO Auto-generated method stub 
     setContentView(R.layout.main); 
    } 

} 

Answer 1

看来folder.getMessages()给null值