【JavaFX】实现计算器小程序

下面是一个简单的JavaFX计算器示例：

import javafx.application.Application;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.geometry.Insets;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.Label;
import javafx.scene.control.TextField;
import javafx.scene.layout.GridPane;
import javafx.scene.layout.HBox;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;

public class Calculator extends Application {
    private TextField resultField;
    private Button clearButton;
    private Button backButton;
    private Button plusButton;
    private Button minusButton;
    private Button multiplyButton;
    private Button divideButton;
    private Button equalButton;
    private Button decimalButton;
    private Button[] numberButtons;

    public static void main(String[] args) {
        launch(args);
    }

    @Override
    public void start(Stage primaryStage) throws Excepti