黑莓屏幕導航

Question

我有一個屏幕名稱下載屏幕當屏幕開始時它將開始下載一些文件，當下載完成後它會自動轉到下一個屏幕。我使用下面的代碼。

public DownloaderScreen() { 
     super(NO_VERTICAL_SCROLL | NO_HORIZONTAL_SCROLL | USE_ALL_HEIGHT 
       | USE_ALL_WIDTH); 

     this.application = UiApplication.getUiApplication(); 
     HorizontalFieldManager outerBlock = new HorizontalFieldManager(USE_ALL_HEIGHT); 
     VerticalFieldManager innerBlock = new VerticalFieldManager(USE_ALL_WIDTH | FIELD_VCENTER); 
     innerBlock.setPadding(0, 10, 0, 10); 
     outerBlock.setBackground(BackgroundFactory 
       .createBitmapBackground(LangValue.dlBgimg)); 
     outerBlock.add(innerBlock); 
     add(outerBlock); 

     phraseHelper = new PhraseHelper(); 
     final String[][] phraseList = phraseHelper.getDownloadList(); 

     gaugeField = new GaugeField("Downloading ", 0, phraseList.length, 0, GaugeField.PERCENT); 
     innerBlock.add(gaugeField); 

     Thread dlTread = new Thread() { 
      public void run() { 
       startDownload(phraseList); 
      } 
     }; 
     dlTread.start(); 

    } 

private void startDownload(String[][] phraseList){ 

     if(phraseList.length!=0){ 

      for(int i=0; i < phraseList.length ; i++){// 
       gaugeField.setValue(i); 
       // code for download 
      } 
     } 
     goToNext(); 
    } 

private void goToNext() { 

final Screen currentScreen = application.getActiveScreen(); 

    if (UiApplication.isEventDispatchThread()) { 
     application.popScreen(currentScreen); 
     application.pushScreen(new HomeScreen()); 
     } else { 
      application.invokeLater(new Runnable() { 
       public void run() { 
        application.popScreen(currentScreen); 
        application.pushScreen(new HomeScreen()); 
       } 
      }); 
     } 
} 

該代碼工作正常，並開始下載文件，當下載完成後，它將前進到下一個屏幕。但是當沒有文件需要下載phraseList數組長度爲零時，它不會前進。我的代碼中有什麼問題？

Answer 1

的GuageField不喜歡從0到0。當長度爲零，不添加GuageField。

Answer 2

更改代碼以

if(phraseList.length!=0){ 

     for(int i=0; i < phraseList.length ; i++){// 
      gaugeField.setValue(i); 
      // code for download 
     } 
     goToNext(); 

    } 
    else{ 
     goToNext(); //if nothing to download, then it will goto the next screen. 
     }