Question

我在JavaFx中看到过Rectangle的例子。但是请任何人可以在输出窗口/场景中提供示例，如果用户放置了所需的宽度和高度，则应自动生成矩形。这是我的例子

            VBox vb = new VBox(20);
            HBox h1  = new HBox(7);
            HBox h2 = new HBox(7);
            Label lebel1 = new Label("X:");
            Label lebel2 = new Label("Y:");

            TextField txt1 = new TextField();
            TextField txt2 = new TextField();

//Converting textfield to integer only    
            ChangeListener<String> forceNumberListener = (observable, oldValue, newValue) -> {
                if (!newValue.matches("\\d*"))
                  ((StringProperty) observable).set(oldValue);
            };

            txt1.textProperty().addListener(forceNumberListener);
            txt2.textProperty().addListener(forceNumberListener);

            double width = Double.parseDouble(txt1.getText());
            double height = Double.parseDouble(txt2.getText());

            Rectangle rect1 = new Rectangle();
            rect1.setHeight(height);
            rect1.setWidth(width);  
            h1.getChildren().addAll(lebel1, txt1);
            h2.getChildren().addAll(lebel2, txt2);  

            vb.getChildren().addAll(h1,h2,rect1);

如果用户将“x”中的任何整数值设置为width，将“y”设置为height，则应在字段下方生成Rectangle。但是这段代码错了，我不知道其他方法。请

非常感谢

Answer 1

您应该使用TextField的onkeyreleased事件处理程序。在此应用程序中，如果两个TextField都输入了数字，则会生成一个矩形。两个TextField都有一个事件处理程序，如果其中一个文本被更改，它会执行相同的操作。这不会捕获任何非双重值。

import javafx.application.Application;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.TextField;
import javafx.scene.input.KeyEvent;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.StackPane;
import javafx.scene.layout.VBox;
import javafx.scene.paint.Color;
import javafx.scene.shape.Rectangle;
import javafx.stage.Stage;

/**
 *
 * @author blj0011
 */
public class JavaFXApplication104 extends Application
{

    @Override
    public void start(Stage primaryStage)
    {


        BorderPane root = new BorderPane();


        VBox vbox = new VBox();
        vbox.setMinWidth(100);

        TextField textfield1 = new TextField();
        TextField textfield2 = new TextField();

        textfield1.setPrefWidth(50);
        textfield1.setPromptText("Enter height");
        textfield1.setOnKeyReleased(new EventHandler<KeyEvent>(){
            @Override
            public void handle(KeyEvent event)
            {  
                if(textfield1.getText().length() > 0 && textfield2.getText().length() > 0)
                {
                    Rectangle rectangle = new Rectangle();
                    rectangle.setHeight(Double.parseDouble(textfield1.getText()));
                    rectangle.setWidth(Double.parseDouble(textfield2.getText()));
                    rectangle.setFill(Color.BLUE);
                    root.setCenter(rectangle);
                }
            }
        });



        textfield2.setPrefWidth(100);
        textfield2.setPromptText("Enter length");
        textfield2.setOnKeyReleased(new EventHandler<KeyEvent>(){
            @Override
            public void handle(KeyEvent event)
            {
                if(textfield1.getText().length() > 0 && textfield2.getText().length() > 0)
                {
                    Rectangle rectangle = new Rectangle();
                    rectangle.setHeight(Double.parseDouble(textfield1.getText()));
                    rectangle.setWidth(Double.parseDouble(textfield2.getText()));
                    rectangle.setFill(Color.BLUE);
                    root.setCenter(rectangle);
                }
            }
        });

        vbox.getChildren().addAll(textfield1, textfield2);
        root.setLeft(vbox);

        Scene scene = new Scene(root, 500, 500);

        primaryStage.setTitle("Hello World!");
        primaryStage.setScene(scene);
        primaryStage.show();
    }

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args)
    {
        launch(args);
    }

}

如何在输出中生成带有用户值的矩形？

1 个答案: