JavaFX学习之道：文本框TextField

Example 8-1 Creating a Text Field

Label label1 = new Label("Name:");
TextField textField = new TextField ();
HBox hb = new HBox();
hb.getChildren().addAll(label1, textField);
hb.setSpacing(10);

Figure 8-2 TextFieldSample Application

Example 8-2 Adding Text Fields to the Application

//Creating a GridPane container
GridPane grid = new GridPane();
grid.setPadding(new Insets(10, 10, 10, 10));
grid.setVgap(5);
grid.setHgap(5);
//Defining the Name text field
final TextField name = new TextField();
name.setPromptText("Enter your first name.");
name.setPrefColumnCount(10);
name.getText();
GridPane.setConstraints(name, 0, 0);
grid.getChildren().add(name);
//Defining the Last Name text field
final TextField lastName = new TextField();
lastName.setPromptText("Enter your last name.");
GridPane.setConstraints(lastName, 0, 1);
grid.getChildren().add(lastName);
//Defining the Comment text field
final TextField comment = new TextField();
comment.setPrefColumnCount(15);
comment.setPromptText("Enter your comment.");
GridPane.setConstraints(comment, 0, 2);
grid.getChildren().add(comment);
//Defining the Submit button
Button submit = new Button("Submit");
GridPane.setConstraints(submit, 1, 0);
grid.getChildren().add(submit);
//Defining the Clear button
Button clear = new Button("Clear");
GridPane.setConstraints(clear, 1, 1);
grid.getChildren().add(clear);

Figure 8-3 Three Text Fields with the Prompt Messages

Example 8-3 Defining Actions for the Submit and Clear Buttons

//Adding a Label
final Label label = new Label();
GridPane.setConstraints(label, 0, 3);
GridPane.setColumnSpan(label, 2);
grid.getChildren().add(label);

//Setting an action for the Submit button
submit.setOnAction(new EventHandler<ActionEvent>() {

@Override
    public void handle(ActionEvent e) {
        if ((comment.getText() != null && !comment.getText().isEmpty())) {
            label.setText(name.getText() + " " + lastName.getText() + ", "
                + "thank you for your comment!");
        } else {
            label.setText("You have not left a comment.");
        }
     }
 });
 
//Setting an action for the Clear button
clear.setOnAction(new EventHandler<ActionEvent>() {

@Override
    public void handle(ActionEvent e) {
        name.setText("");
        lastName.setText("");
        comment.setText("");
        label.setText(null);
    }
});