Question

所以我正在努力学习使用JavaFX和场景构建器，但是当我试图让小费计算器工作时我遇到了一个问题，因为我试图得到它以便当我移动时滑块改变尖端百分比，尖端数量和总数将自动更改，无需单击计算按钮，这里是代码和应用程序的图片！任何帮助表示赞赏！

package tipcalculator;

import java.math.BigDecimal;
import java.math.RoundingMode;
import java.text.NumberFormat;
import javafx.beans.value.ChangeListener;
import javafx.beans.value.ObservableValue;
import javafx.event.ActionEvent;
import javafx.fxml.FXML;
import javafx.scene.control.Label;
import javafx.scene.control.Slider;
import javafx.scene.control.TextField;

/**
 *
 * @author joshd
 */
public class TipCalculatorController {

    private static final NumberFormat currency = NumberFormat.getCurrencyInstance();
    private static final NumberFormat percent
            = NumberFormat.getPercentInstance();
    private BigDecimal tipPercentage = new BigDecimal(0.15);
    @FXML
    private TextField amountTextField;
    @FXML
    private Label tipPercentageLabel;
    @FXML
    private Slider tipPercentageSlider;
    @FXML
    private TextField tipTextField;
    @FXML
    private TextField totalTextField;

    @FXML
    private void calculateButtonPressed(ActionEvent event) {
        try {
            BigDecimal amount = new BigDecimal(amountTextField.getText());
            BigDecimal tip = amount.multiply(tipPercentage);
            BigDecimal total = amount.add(tip);
            tipTextField.setText(currency.format(tip));
            totalTextField.setText(currency.format(total));
        } catch (NumberFormatException ex) {
            amountTextField.setText("Enter amount");
            amountTextField.selectAll();
            amountTextField.requestFocus();
        }
    }

    public void initialize() {
        currency.setRoundingMode(RoundingMode.HALF_UP);
        tipPercentageSlider.valueProperty().addListener(new ChangeListener<Number>() {
            @Override
            public void changed(ObservableValue<? extends Number> ov, Number oldValue, Number newValue) {
                tipPercentage = BigDecimal.valueOf(newValue.intValue() / 100.0);
                tipPercentageLabel.setText(percent.format(tipPercentage));
            }
        }); 
    }

}

Answer 1

将监听器添加到text的{{1}}属性和更新计算的amountTextField value属性。此外，您可以使用绑定来设置tipPercentageSlider：

的文本

tipPercentageLabel

JavaFX小费计算器滑块

1 个答案: