java - 单击两个不同的复选框(一个接着另一个)在 netbeans 中调用两个不同的窗口会出现异常

Question

这是复选框的两个函数

复选框:ActiveBox

private void Active_BoxActionPerformed(java.awt.event.ActionEvent evt) {
    if (Active_Box.isSelected() == true) {
       Active_Link.main(args);
    }
}

复选框:SQLBox

private void SQL_boxActionPerformed(java.awt.event.ActionEvent evt) {
    if (ESC_box.isSelected() == true) {
       ESC.main(args);
    }
}

Active.java

public class Active extends Application { 
private final Node rootIcon=null; 

TreeItem<String> rootNode = new TreeItem<String>("My Workflows");

public static void main(String[] args) {
    launch(args);
}

public void start(Stage stage) {
    rootNode.setExpanded(true);
    BufferedReader reader = null;

    try {
       reader = new BufferedReader(new FileReader("D:\\onlyForms.txt"));

       String line=null;

       while ((line = reader.readLine()) != null) {
           if (line.indexOf("Checking") >= 0) {
               String next=reader.readLine();
               if(next.contains("Passed_qualification ")) {
                  TreeItem<String> depNode = new TreeItem<String>(line)              
                  depNode.setExpanded(false);
                  TreeItem<String> depNode1 = new TreeItem<String>(next); 
                  depNode.getChildren().add(depNode1);
                  String next1=reader.readLine();
                  TreeItem<String> depNode2 = new TreeItem<String>(next1);
                  depNode.getChildren().add(depNode2);
                  rootNode.getChildren().add(depNode);
               }
               if(next.contains("Failed_qualification ")) {
                  TreeItem<String> depNode = new TreeItem<String>(line);
                  depNode.setExpanded(false);
                  TreeItem<String> depNode1 = new TreeItem<String>(next); 
                  depNode.getChildren().add(depNode1);
                  String next1=reader.readLine();
                  TreeItem<String> depNode2 = new TreeItem<String>(next1);
                  depNode.getChildren().add(depNode2);
                  rootNode.getChildren().add(depNode);
        }
        stage.setTitle("Escalations");
        VBox box = new VBox();
        final Scene scene = new Scene(box, 500, 500);
        scene.setFill(Color.LIGHTGRAY);
        box.setStyle("-fx-font: 18 arial;"); 
        TreeView<String> treeView = new TreeView<String>(rootNode);
        box.getChildren().add(treeView);
        stage.setScene(scene);
        stage.show();
    }
}

SQL.java

public class SQL extends Application { 
  static String str=null;

  static  String next_line=null;

  static BufferedReader br;

  private final Node rootIcon; 

  public static void main(String[] args) throws IOException {           
     launch(args);

  }

  public SQL() {
      this.rootIcon = null;
  }

  public void start(Stage stage) throws IOException {
    rootNode.setExpanded(true);

    BufferedReader reader=null;

    try
    {
      FileInputStream f=new FileInputStream("D:\\SQL\\SQL_XML_TXT.txt");
      reader = new BufferedReader(new InputStreamReader(f));
      String line=null;
      while ((line = reader.readLine()) != null) {   
         if (line.indexOf("TID") >=0) { 
           String next1=reader.readLine();
           String next2=reader.readLine();
           String next3=reader.readLine();
           String next4=reader.readLine();
           String next5=reader.readLine();
           String next6=reader.readLine();
           String next7=reader.readLine();

           String time_date=SQL.GetTime(br);

           if(((next7.indexOf("OK"))<0)) {
              if(((next7.indexOf("SQL Trace Log- ON"))<0)) {  
                TreeItem<String>depNode=new TreeItem<String>(line);
                depNode.setExpanded(false);
                TreeItem<String> depNode1 = new TreeItem<String>(next1); 
                depNode.getChildren().add(depNode1);

                TreeItem<String> depNode2=new TreeItem<String>(next2);

                depNode1.getChildren().add(depNode2);

                TreeItem<String> depNode3=new TreeItem<String>(next3);
                depNode1.getChildren().add(depNode3);

                TreeItem<String> depNode4=new TreeItem<String>(next4);

                depNode1.getChildren().add(depNode4);   

                TreeItem<String> depNode5=new TreeItem<String>(next5);
                depNode1.getChildren().add(depNode5);

                TreeItem<String> depNode6=new TreeItem<String>(next6);

                depNode1.getChildren().add(depNode6);  

                TreeItem<String> depNode7=new TreeItem<String>(next7);

                depNode1.getChildren().add(depNode7);  
                rootNode.getChildren().add(depNode);
              }

            } 
          }
      }

   }        
   stage.setTitle("Escalations");
   VBox box = new VBox();
   final Scene scene = new Scene(box, 500, 500);
   scene.setFill(Color.LIGHTGRAY);
   box.setStyle("-fx-font: 18 arial;");
   TreeView<String> treeView = new TreeView<String>(rootNode);
   box.getChildren().add(treeView);
   stage.setScene(scene);
   stage.show();
  }
}

当我单击两个复选框时，第一个窗口将打开，当我单击另一个复选框时，它会引发以下异常

"Exception in thread "AWT-EventQueue-0" java.lang.IllegalStateException: Application launch must not be called more than once at com.sun.javafx.application.LauncherImpl.launchApplication(LauncherImpl.java:137) at com.sun.javafx.application.LauncherImpl.launchApplication(LauncherImpl.java:118) at javafx.application.Application.launch(Application.java:241)

Answer 1

不要尝试多次调用javafx.application.Application.launch。这会导致你的异常。如果您想创建一个新窗口，只需创建一个新的 Stage 并将新内容添加到此阶段(因为您是从 Swing 创建窗口，所以您必须从 JFX 线程执行此操作；请参阅最后的代码片段):

Stage stage = new Stage();
// add your content here
stage.show();

如果您仍然希望将 SQL 和 Active 作为应用程序的可能入口点，我建议编写基本上与您的 start 相同的方法 方法(减去 Stage 部分)，但返回 Scene 对象，例如像这样的东西:

public class Active extends Application {

    public static Scene createScene() {
        Scene scene = //... insert your code here

        return scene;
    }

    @Override
    public void start(Stage stage) throws Exception {
        stage.setScene(createScene());
        stage.show();
    }

    public static void main(String[] args) {
        launch(args);
    }

}

并像这样更改 CheckBox 函数:

private void Active_BoxActionPerformed(java.awt.event.ActionEvent evt) {
    if (Active_Box.isSelected() == true) {
        Platform.runLater(() -> { // invoke "Runnable" from JFX thread
            Stage stage = new Stage();
            stage.setScene(Active.createScene());
            stage.show();
        });
    }
}

并对 SQL 部分执行相同的操作。

如果您不需要 SQL 和 Active 作为入口点，那么您当然不需要扩展 Application 。 .