如何在FXML加载后立即请求将焦点集中在文本字段上？

Question

if(textField.isVisible()) textField.requestFocus();

    //The controller class for the FXML containing the button that is pressed to go to the FXML with the TextField
public class StartScene {
    @FXML
    BorderPane contentPane; //Where the other fxml file will be loaded
    private String path = "../fxml/fxmlFile.fxml";
    private static Parent component = null;
    @FXML
    private void initialize() throws IOException {

        component = FXMLLoader.load(getClass().getResource(path));
    }
    @FXML
    //This method is set to the onAction of a button
    private void loadComponent(){
        if (!contentPane.getChildren().contains(component)) {
            contentPane.getChildren().clear();
            contentPane.setCenter(component);
        }
        else { System.out.println("Component already inserted"); }
     }
}

public class TextFieldSceneController {
    @FXML
    TextField textField;
    @FXML
    private void initialize() {
        textField.setPromptText("Prompt");
    }
}

StartScene得FXML：

<?import javafx.scene.layout.VBox?>
<?import javafx.scene.control.Button?>
<?import javafx.scene.layout.BorderPane?>
<?import javafx.scene.layout.StackPane?>

<StackPane minHeight="500" minWidth="900" xmlns:fx="http://javafx.com/fxml"
       fx:controller="StartScene" >
    <BorderPane fx:id="borderPane">
        <left>
            <VBox minHeight="500" prefWidth="250" minWidth="10">
                    <Button text="BUTTON" minHeight="30" minWidth="100" prefWidth="250"  alignment="CENTER" onAction="#loadComponent"/>
             </VBox>
        </left>
        <center>
            <BorderPane minWidth="600" minHeight="500" fx:id="contentPane">
                 <children>
                 </children>
            </BorderPane>
        </center>
    </BorderPane>
</StackPane>

具有TextField场景的FXML：

<?import javafx.scene.control.*?>
<?import javafx.scene.layout.*?> 

<StackPane xmlns="http://javafx.com/javafx" xmlns:fx="http://javafx.com/fxml"
       fx:controller="TextFieldSceneController" prefHeight="600.0" maxWidth="800.0" fx:id="root">
    <VBox fx:id="base">
        <children>
            <TextField fx:id="textField" alignment="CENTER"/>
        </children>
    </VBox>
</StackPane>

Answer 1

你有几个问题。

首先，您正在实际需要组件之前加载它。这意味着initialize()方法早在您在BorderPane中实际显示组件之前就已经调用并完成了运行。

相反，您应该只在单击按钮后加载FXML文档（将加载移到LoadComponent()方法）。