除非我调整窗口javaFx的大小，否则GridPane不可见

Question

当我启动应用程序时，TitledPane不会显示我添加的GridPane。令人惊讶的是，当我增加/减少窗口宽度时，它是可见的。我在哪里失踪了？

这是完整的代码：

package com.ct.bic.comparator;
import javafx.application.Application;
import javafx.geometry.Insets;
import javafx.geometry.Pos;
import javafx.scene.Scene;
import javafx.scene.control.Accordion;
import javafx.scene.control.Button;
import javafx.scene.control.Label;
import javafx.scene.control.PasswordField;
import javafx.scene.control.TextField;
import javafx.scene.control.TitledPane;
import javafx.scene.layout.GridPane;
import javafx.scene.text.Font;
import javafx.scene.text.FontWeight;
import javafx.stage.Stage;
public class Comparator extends Application {
    @Override
    public void start(Stage stage) {
        GridPane dbGrid = new GridPane();
        dbGrid.setId("dbGrid");
        dbGrid.setAlignment(Pos.TOP_LEFT);
        dbGrid.setHgap(10);
        dbGrid.setVgap(10);
        dbGrid.setPadding(new Insets(25, 25, 25, 25));
        Label dbConnection = new Label("Database Configuration");
        dbConnection.setId("dbConnection");
        dbConnection.setFont(Font.font("Tahoma", FontWeight.NORMAL, 20));
        dbGrid.add(dbConnection, 0, 0, 2, 1);
        Label server = new Label("Server");
        server.setId("server");
        dbGrid.add(server, 0, 1);
        TextField serverText = new TextField();
        serverText.setId("serverText");
        dbGrid.add(serverText, 1, 1);
        Label database = new Label("Database");
        database.setId("database");
        dbGrid.add(database, 0, 2);
        TextField databaseText = new TextField();
        databaseText.setId("databaseText");
        dbGrid.add(databaseText, 1, 2);
        Label user  = new Label("User");
        user.setId("user");
        dbGrid.add(user, 0, 3);
        TextField userText = new TextField();
        userText.setId("userText");
        dbGrid.add(userText, 1, 3);
        Label password  = new Label("Password");
        password.setId("password");
        dbGrid.add(password, 0, 4);
        PasswordField passwordText = new PasswordField();
        passwordText.setId("passwordText");
        dbGrid.add(passwordText, 1, 4);
        dbGrid.setId("passwordText");
        /*GridPane dbGrid = DatabaseInputGrid.getDatabaseGrid();*/
        TitledPane tp = new TitledPane("Database Configuration", dbGrid);
        Scene scene = new Scene(tp, 500,500);
        stage.setScene(scene);
        stage.setTitle("Bic-Java Output Comparator Pro");
        stage.show();
    }
    public static void main(String[] args) {
        launch(args);
    }
}

Answer 1

我不知道确切的原因，但如果将TitledPane用作Scene的根，似乎不会调整其大小。

我试过这样的东西：

VBox vbox = new VBox();
vbox.getChildren().add(tp);
Scene scene = new Scene(vbox, 500,500);

然后一切都按预期进行。

编辑：我在这里找到了这个：

不要明确设置标题窗格，因为当标题窗格打开或关闭。

因此，我的猜测是，当您将TitledPane设置为场景的根时，它会尝试设置首选高度，这会导致提到的"意外行为"。