Java GridPane元素最初超出边界，仅在调整窗口大小后捕捉到位

我希望创建一个2x2网格窗格，其中所有子按钮都是网格窗格的25%。当我用GridPane填充StackPane时，子按钮会超出约束。只有在我调整窗口大小后，子按钮才会捕捉到它们的位置

<VBox fx:id="answerableList" styleClass="pane-with-border" minWidth="340" prefWidth="340" VBox.vgrow="ALWAYS">
          <padding>
            <Insets top="10" right="10" bottom="10" left="10" />
          </padding>
          <StackPane fx:id="answerableListPanelPlaceholder" VBox.vgrow="ALWAYS"/>
</VBox>

调整大小之前：

---

调整大小后：

请..更准确地说：第二个片段何时发生与创建/显示场景有关？你能在没有css风格的情况下重现这个问题吗？如果没有，添加一个最小版本的css，仍然允许重现问题。

answerableListPanelPlaceholder.getChildren().add(answersGridPane.getRoot());

<GridPane fx:id="cardPane" maxWidth="Infinity" maxHeight="Infinity"
          xmlns="http://javafx.com/javafx/8" xmlns:fx="http://javafx.com/fxml/1"
          alignment="center" >
    <columnConstraints>
        <ColumnConstraints hgrow="ALWAYS" minWidth="10.0" percentWidth="50.0"/>
        <ColumnConstraints hgrow="ALWAYS" minWidth="10.0" percentWidth="50.0"/>
    </columnConstraints>

    <rowConstraints>
        <RowConstraints vgrow="ALWAYS" minHeight="10.0" percentHeight="50.0"/>
        <RowConstraints vgrow="ALWAYS" minHeight="10.0" percentHeight="50.0"/>
    </rowConstraints>

    <children>
        <Button styleClass="option-label" fx:id="option1" text="\$option1" wrapText="true"
               GridPane.columnIndex="0" GridPane.rowIndex="0">
        </Button>

        <Button styleClass="option-label" fx:id="option2" text="\$option2" wrapText="true"
               GridPane.columnIndex="1" GridPane.rowIndex="0">

        </Button>

        <Button styleClass="option-label" fx:id="option3" text="\$option3" wrapText="true"
               GridPane.columnIndex="0" GridPane.rowIndex="1">

        </Button>
        <Button styleClass="option-label" fx:id="option4" text="\$option4" wrapText="true"
               GridPane.columnIndex="1" GridPane.rowIndex="1">
        </Button>
    </children>

</GridPane>