我正在使用javafx创建一个窗格,要求贷款金额和年数计算每月和总付款的数额,根据年利率从.125增加5%到8%。
我想以初始窗格下方的表格形式打印出来。但是,我不知道如何在文本区域变量中添加多行文本。
这是我的代码:
import javafx.application.Application;
import javafx.stage.Stage;
import javafx.scene.Scene;
import javafx.scene.layout.FlowPane;
import javafx.scene.layout.BorderPane;
import javafx.scene.control.ScrollPane;
import javafx.scene.control.Button;
import javafx.scene.control.Label;
import javafx.scene.control.TextField;
import javafx.scene.control.TextArea;
public class LoanTable extends Application {
// create TextField and button variables
private TextField tfAmount = new TextField();
private TextField tfYears = new TextField();
private Button btCalc = new Button("Show Table");
private TextArea taResult = new TextArea();
@Override
public void start(Stage primaryStage) {
// create FlowPane and set properties
FlowPane pane = new FlowPane();
pane.setHgap(10);
tfAmount.setPrefColumnCount(3);
tfYears.setPrefColumnCount(3);
pane.getChildren().addAll(new Label("Loan Amount"), tfAmount, new Label("Number of Years"), tfYears, btCalc);
// create ScrollPane and set properties
ScrollPane scrollPane = new ScrollPane(taResult);
taResult.setEditable(false);
// create BorderPane and add FlowPane and ScrollPane
BorderPane borderPane = new BorderPane();
borderPane.setCenter(pane);
borderPane.setBottom(scrollPane);
// create and register a handler
btCalc.setOnAction(e -> calcTable());
// create a scene and place it in the stage
Scene scene = new Scene(borderPane);
primaryStage.setTitle("Loan-Table");
primaryStage.setScene(scene);
primaryStage.show();
}
// create a method to calculate monthly payment
public double calcMonthly(double interestRate) {
double loanAmount = Double.parseDouble(tfAmount.getText());
int years = Integer.parseInt(tfYears.getText());
double monthlyInterestRate = interestRate / 1200;
double monthlyPayment = loanAmount * monthlyInterestRate / (1 - 1 / Math.pow(1 + monthlyInterestRate, years * 12));
return monthlyPayment;
}
// create a method to calculate total payment
public double calcTotal(double interestRate, double monthlyPayment) {
int years = Integer.parseInt(tfYears.getText());
double totalPayment = monthlyPayment * years * 12;
return totalPayment;
}
private void calcTable() {
// get values from text fields
double interestRate = 5;
// display table header
taResult.setText(String.format("%13s%20s%18s\n", "Interest Rate", "Monthly Payment", "Total Payment"));
// print rest of table
for (int i = 1; i < 26; interestRate+=.125, i++) {
double x = calcMonthly(interestRate);
taResult.setText(String.format("%5.3f%19.2f%22.2f\n", interestRate, calcMonthly(interestRate), calcTotal(interestRate, x)));
}
}
public static void main(String args[]) {
Application.launch(args);
}
}
问题来自&#34; //打印表的其余部分&#34;环。如何在taResult变量中添加多行文本?当我运行这个程序时,我最终得到了表的最后一行。输入10000(贷款金额)和5(年数)输出为:
8.000 202.76 12165.84
但我想要的输出是:
Interest Rate Monthly Payment Total Payment
5.000 188.71 11322.74
5.125 189.29 11357.13
5.250 189.86 11391.59
5.375 190.44 11426.11
5.500 191.01 11460.70
5.625 191.59 11495.35
5.750 192.17 11530.06
5.875 192.75 11564.84
6.000 193.33 11599.68
6.125 193.91 11634.59
6.250 194.49 11669.56
6.375 195.08 11704.59
6.500 195.66 11739.69
6.625 196.25 11774.85
6.750 196.83 11810.08
6.875 197.42 11845.37
7.000 198.01 11880.72
7.125 198.60 11916.14
7.250 199.19 11951.62
7.375 199.79 11987.16
7.500 200.38 12022.77
7.625 200.97 12058.44
7.750 201.57 12094.18
7.875 202.17 12129.97
8.000 202.76 12165.84
我希望我明白这个问题。
答案 0 :(得分:4)
我需要taResult.appendText --- .appendText就是我想要的。
很抱歉浪费任何人阅读此内容的时间。