!4 fix: 关联文件打开会出现两个tap

Merge pull request !4 from 一个大转盘/master

src/main/java/org/jcnc/jnotepad/LunchApp.java

@@ -56,7 +56,9 @@ public class LunchApp extends Application {
             List<String> rawParameters = getParameters().getRaw();
             threadPool.execute(() -> {
                 TextArea textArea = controller.openAssociatedFileAndCreateTextArea(rawParameters);
-                Platform.runLater(() -> updateUIWithNewTextArea(textArea));
+                if (!Objects.isNull(textArea)) {
+                    Platform.runLater(() -> updateUIWithNewTextArea(textArea));
+                }
             });
         }
     }

src/main/java/org/jcnc/jnotepad/controller/manager/Controller.java

@@ -35,12 +35,12 @@ public class Controller implements ControllerInterface {
         if (!rawParameters.isEmpty()) {
             String filePath = rawParameters.get(0);
             openAssociatedFile(filePath);
+            return null;
+        } else {
+            TextArea textArea = createNewTextArea();
+            configureTextArea(textArea);
+            return textArea;
         }
-
-        TextArea textArea = createNewTextArea();
-        configureTextArea(textArea);
-
-        return textArea;
     }
 
     /**