在JavaFX中使用FXML和Controller創建場景

Question

我在GridPane中創建了一個9x9 GridPane ，並且我想向每個單元格添加單獨的TextFields 。 我敢肯定還有其他方法可以創建像這樣的大表，但是我並沒有在尋找其他方法來完成此操作（這是我學習經驗的一部分）。 我不想在FXML / SceneBuilder中添加TextFields 。 我想跟蹤它們在數組中的位置，以便可以訪問它們的各個值，因此我想一次在Controller中創建一個值，然后將它們添加到數組以及GridPane每個單元格中。

這是我的控制器嘗試添加TextFields （我嘗試在將它們添加到數組之前創建它們）：

@FXML
private GridPane gridPane;
private TextField myTextField[][] = new TextField[9][9];
.
.
.
@Override
public void initialize(URL url, ResourceBundle rb) {
  for (int i = 0; i < 9; ++i){
        for (int j = 0; j < 9; ++j){

            TextField tempTextField = new TextField();
            Font myFont = new Font("System",38);
            tempTextField.setFont(myFont);
            tempTextField.setText(i + ", " + j);
            tempTextField.setPrefSize(70, 70);
            myTextField[i][j] = tempTextField;
            gridPane.add(tempTextField,i,j);
            System.out.println("TextField " +i+j+" Created!");
        }
    } 
}

在運行時之前沒有出現錯誤，並且場景未更新。

編輯：我看了StackTrace並注意到我得到一個空指針

gridPane.add(tempTextField,i,j);

FXML文件 ：

<?xml version="1.0" encoding="UTF-8"?>

<?import javafx.scene.text.*?>
<?import java.lang.*?>
<?import java.util.*?>
<?import javafx.scene.*?>
<?import javafx.scene.control.*?>
<?import javafx.scene.layout.*?>

<AnchorPane id="AnchorPane" prefHeight="654.0" prefWidth="747.0" xmlns:fx="http://javafx.com/fxml/1" xmlns="http://javafx.com/javafx/8" fx:controller="sudokusolver.FXMLDocumentController">
    <children>
      <BorderPane prefHeight="654.0" prefWidth="747.0">
         <center>
            <GridPane fx:id="gridPane" gridLinesVisible="true" prefHeight="198.0" prefWidth="200.0" BorderPane.alignment="CENTER">
               <columnConstraints>
              <ColumnConstraints hgrow="SOMETIMES" minWidth="10.0" prefWidth="100.0" />
                  <ColumnConstraints hgrow="SOMETIMES" minWidth="10.0" prefWidth="100.0" />
                  <ColumnConstraints hgrow="SOMETIMES" minWidth="10.0" prefWidth="100.0" />
                  <ColumnConstraints hgrow="SOMETIMES" minWidth="10.0" prefWidth="100.0" />
                  <ColumnConstraints hgrow="SOMETIMES" minWidth="10.0" prefWidth="100.0" />
                  <ColumnConstraints hgrow="SOMETIMES" minWidth="10.0" prefWidth="100.0" />
                  <ColumnConstraints hgrow="SOMETIMES" minWidth="10.0" prefWidth="100.0" />
                  <ColumnConstraints hgrow="SOMETIMES" minWidth="10.0" prefWidth="100.0" />
                  <ColumnConstraints hgrow="SOMETIMES" minWidth="10.0" prefWidth="100.0" />
               </columnConstraints>
               <rowConstraints>
                  <RowConstraints minHeight="10.0" prefHeight="30.0" vgrow="SOMETIMES" />
                  <RowConstraints minHeight="10.0" prefHeight="30.0" vgrow="SOMETIMES" />
                  <RowConstraints minHeight="10.0" prefHeight="30.0" vgrow="SOMETIMES" />
                  <RowConstraints minHeight="10.0" prefHeight="30.0" vgrow="SOMETIMES" />
                  <RowConstraints minHeight="10.0" prefHeight="30.0" vgrow="SOMETIMES" />
                  <RowConstraints minHeight="10.0" prefHeight="30.0" vgrow="SOMETIMES" />
                  <RowConstraints minHeight="10.0" prefHeight="30.0" vgrow="SOMETIMES" />
                  <RowConstraints minHeight="10.0" prefHeight="30.0" vgrow="SOMETIMES" />
                  <RowConstraints minHeight="10.0" prefHeight="30.0" vgrow="SOMETIMES" />
               </rowConstraints>
            </GridPane>
         </center>
         <bottom>
            <HBox alignment="CENTER" prefHeight="40.0" prefWidth="747.0" BorderPane.alignment="CENTER">
               <children>
                  <FlowPane prefHeight="200.0" prefWidth="200.0">
                     <children>
                        <Button fx:id="loadButton" alignment="CENTER" contentDisplay="CENTER" minHeight="-Infinity" minWidth="-Infinity" onAction="#setGrid" prefHeight="35.0" prefWidth="100.0" text="Load Board" />
                          <Button fx:id="solveButton" alignment="CENTER" contentDisplay="CENTER" minHeight="-Infinity" minWidth="-Infinity" onAction="#sudokuSolve" prefHeight="35.0" prefWidth="100.0" text="Solve" />
                     </children>
                  </FlowPane>
               </children>
            </HBox>
         </bottom>
      </BorderPane>
    </children>
</AnchorPane>

Answer 1

嘗試在控制器中實現javafx.fxml.Initializable接口，並將setGrid()邏輯移至其隨附的方法。