新任務導致java.lang.IllegalStateException：不上，即使Platform.runLater FX應用程序線程（）包裹

Question

我試圖在Platform.runLater（）包裹ObservableList，他們卻給我一個錯誤：

local variables referenced from an inner class must be final or effectively final

我想不出有什麼解決這個錯誤的。這裏是我的代碼：

Task task = new Task<Void>() { 
      @Override public Void call() {     
       try { 

        for (int i = 0; i < obLstDataset.size(); i++){ 
         // **************************       
         //doing other stuff here 
         // ************************** 
         if (pageVLEDEResult.contains("something")) {        
          Platform.runLater(new Runnable() { 
          @Override 
          public void run() { 
            obLstInvalid.add((String)obLstDataset.get(i));  
           } 
          }); 
         } 

         else if (pageVLEDEResult.contains("something else")){ 
          if (i!=0){ 
           i--; 
          } 
         } 

         updateProgress (i+1, obLstDataset.size()); 

        } 

       } catch (IOException | FailingHttpStatusCodeException ex) { 
        Logger.getLogger(VehicleLicenceExpiryDateEnquirer.class.getName()).log(Level.SEVERE, null, ex); 
       } 
       return null; 
      } 
     }; 

Answer 1

我認爲你需要使runLater最終的變量被訪問。另外，在for循環中修改for循環變量（在本例中爲i）是非常糟糕的做法。所以我已經將它重新寫入while循環。

Task task = new Task<Void>() { 
     @Override public Void call() {     
      try { 
       int i=0; 
       do { 
        // **************************       
        //doing other stuff here 
        // ************************** 
        if (pageVLEDEResult.contains("something")) {       
         final List <not sure what class this is> fobLstInvalid = obLstInvalid; 
         final List <not sure what class this is> fobLstDataset = obLstDataset; 
         final int fi = i; 

         Platform.runLater(new Runnable() { 
         @Override 
         public void run() { 
           obLstInvalid.add((String)obLstDataset.get(fi));  
          } 
         }); 
        } 

        else if (pageVLEDEResult.contains("something else")){ 
         if (i!=0){ 
          i--; 
         } 
        } 

        updateProgress (i+1, obLstDataset.size()); 
        i++; 
       } while (i < obLstDataset.size()) 

      } catch (IOException | FailingHttpStatusCodeException ex) { 
       Logger.getLogger(VehicleLicenceExpiryDateEnquirer.class.getName()).log(Level.SEVERE, null, ex); 
      } 
      return null; 
     } 
    };