如何从对象数组列表中获取项

Question

那么我该怎么"打开"约会对象的数组列表呢？我尝试过迭代，但它得到了2个正确的显示，或者重复了最后一个条目。我需要将文本字段设置为对象数组中的一个变量。我该怎么做？这是一个将约会保存到数组列表中的日历，注意到该列表属于名为约会的对象类型。我很快就要完成了，我就是不知道如何在文本字段中显示或设置信息。

import java.awt.Color;
import java.util.*;
import javafx.application.Application;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.geometry.Insets;
import javafx.geometry.Pos;
import javafx.scene.Scene;
import javafx.scene.control.*;
import javafx.scene.layout.*;
import javafx.stage.Stage;

public class Calendario extends Application {
private TextField s = new TextField();
private TextField m = new TextField();
private TextField t = new TextField();
private TextField w = new TextField();
private TextField th = new TextField();
private TextField f = new TextField();
private TextField st = new TextField();
private TextField dom = new TextField();
private TextField lun = new TextField();
private TextField mar = new TextField();
private TextField mie = new TextField();
private TextField hue = new TextField();
private TextField vir = new TextField();
private TextField sab = new TextField();
private Label firstd = new Label("Sunday");
private Label secd = new Label("Monday");
private Label thrd = new Label("Tuesday");
private Label fortd = new Label("Wednesday");
private Label fiftd = new Label("Thursday");
private Label sistd = new Label("Friday");
private Label svnd = new Label("Saturday");
private Button submit = new Button();
private Button open = new Button();
private Button clear = new Button();
private ArrayList<Appointment> date = new ArrayList<Appointment>();
public class Appointment{
DayOfWeek day;
String tiempo;
String d;
Appointment(String tiempo,String d){
if(Character.isDigit(tiempo.charAt(0)) && tiempo.endsWith("a") || 
tiempo.endsWith("p")){
this.tiempo = tiempo;
}
else{
throw new IllegalArgumentException("First input must be numeric and a for am"+
"p for pm");
}
this.d = d;
}
}
public void submit(){
for (DayOfWeek day : DayOfWeek.values()){
switch (day){
case SUNDAY: 
Appointment sunday = new Appointment(s.getText(),dom.getText());
date.add(sunday);
break;
case MONDAY:
Appointment monday = new Appointment(m.getText(),lun.getText());
date.add(monday);
break;
case TUESDAY:
Appointment tuesday = new Appointment(t.getText(),mar.getText());
date.add(tuesday);
break;
case WEDNESDAY:
Appointment wednesday = new Appointment(w.getText(),mie.getText());
date.add(wednesday);
break;
case THURSDAY:
Appointment thursday = new Appointment(th.getText(),hue.getText());
date.add(thursday);
break;
case FRIDAY:
Appointment friday = new Appointment(f.getText(),vir.getText());
date.add(friday);
break;
case SATURDAY:
Appointment saturday = new Appointment(st.getText(),sab.getText());
date.add(saturday);
break; 
default:
System.out.println("Error oh no help master");
break;
}
}
}
public void open(){

}
public void clear(){
date.clear();
}
@Override
public void start(Stage primaryStage) {
submit.setText("Submit");
submit.setStyle("-fx-background-color: #00ff00");
submit.setOnAction(new EventHandler<ActionEvent>() {
@Override
public void handle(ActionEvent event) {
submit();
}
});
open.setText("Open");
open.setOnAction(new EventHandler<ActionEvent>() {
@Override
public void handle(ActionEvent event) {
open();
}
});
clear.setText("Clear");
clear.setStyle("-fx-background-color: #ff0000");
clear.setOnAction(new EventHandler<ActionEvent>() {
@Override
public void handle(ActionEvent event) {
clear();
}
});
HBox frame = new HBox();
VBox sun = new VBox(10);
VBox mon = new VBox(10);
VBox tues = new VBox(10);
VBox wed = new VBox(10);
VBox thur = new VBox(10);
VBox fri = new VBox(10);
VBox sat = new VBox(10);
sun.getChildren().addAll(firstd,s,dom);
mon.getChildren().addAll(secd,m,lun);
tues.getChildren().addAll(thrd,t,mar);
wed.getChildren().addAll(fortd,w,mie);
thur.getChildren().addAll(fiftd,th,hue,clear);
fri.getChildren().addAll(sistd,f,vir,open);
sat.getChildren().addAll(svnd,st, sab,submit);
firstd.setTranslateX(20);
secd.setTranslateX(20);
thrd.setTranslateX(20);
fortd.setTranslateX(10);
fiftd.setTranslateX(20);
sistd.setTranslateX(20);
svnd.setTranslateX(20);
frame.getChildren().addAll(sun,mon,tues,wed,thur,fri,sat);
Scene scene = new Scene(frame, 600, 300);
primaryStage.setTitle("Appoinment Calendar");
primaryStage.setScene(scene);
primaryStage.show();
}
/**
* @param args the command line arguments
*/
public static void main(String[] args) {
launch(args);
}

Answer 1

代码写得不好。只要考虑一下所有日子的代码有多相似。为什么要重复一遍，而不是想出一个合适的数据结构，让你更方便地访问对象？既然可以创建2并使用循环重复该过程，为什么要创建2 x 7TextFields？

你还需要做的一件事是将一周中的哪一天实际存储在Appointment中。

以下代码中的open实现假设date列表的内容已经包含正确的值，即使当前代码仅恢复上次提交的值，如果用户编辑TextFields。

private ArrayList<Appointment> date = new ArrayList<Appointment>();
public static class Appointment {
final DayOfWeek day;
final String tiempo;
final String d;
Appointment(String tiempo, String d, DayOfWeek day) {
if (Character.isDigit(tiempo.charAt(0)) && tiempo.endsWith("a") || tiempo.endsWith("p")) {
this.tiempo = tiempo;
} else {
throw new IllegalArgumentException("First input must be numeric and a for am" + "p for pm");
}
this.d = d;
this.day = day;
}
}
public void submit() {
// add appointment for each entry in the map
inputs.forEach((day, inputs) -> {
date.add(new Appointment(inputs[0].getText(), inputs[1].getText(), day));
});
}
public void open() {
// clear fields
inputs.values().stream().flatMap(Arrays::stream).forEach(TextField::clear);
// set text for all elements of date
date.forEach(appointment -> {
TextField[] fields = inputs.get(appointment.day);
fields[0].setText(appointment.tiempo);
fields[1].setText(appointment.d);
});
}
public void clear() {
date.clear();
}
private final Map<DayOfWeek, TextField[]> inputs = new EnumMap<>(DayOfWeek.class);
@Override
public void start(Stage primaryStage) {
Button submit = new Button("Submit");
submit.setStyle("-fx-background-color: #00ff00");
submit.setOnAction(event -> submit());
Button open = new Button("Open");
open.setOnAction(event -> open());
Button clear = new Button("Clear");
clear.setStyle("-fx-background-color: #ff0000");
clear.setOnAction(event -> clear());
GridPane grid = new GridPane();
grid.setVgap(10);
Locale locale = Locale.ENGLISH;
TextStyle textStyle = TextStyle.FULL;
Insets headerMargin = new Insets(0, 0, 0, 20);
// add inputs and label for days starting with sunday and store inputs in map
for (int i = 0; i < 7; i++) {
DayOfWeek day = DayOfWeek.SUNDAY.plus(i);
Label label = new Label(day.getDisplayName(textStyle, locale));
GridPane.setMargin(label, headerMargin);
TextField timeField = new TextField();
TextField dField = new TextField();
inputs.put(day, new TextField[] { timeField, dField });
grid.addColumn(i, label, timeField, dField);
}
HBox buttonContainer = new HBox(10, clear, open, submit);
buttonContainer.setAlignment(Pos.TOP_RIGHT);
VBox.setMargin(buttonContainer, new Insets(0, 20, 0, 0));
VBox root = new VBox(10, grid, buttonContainer);
Scene scene = new Scene(root, 600, 300);
primaryStage.setTitle("Appoinment Calendar");
primaryStage.setScene(scene);
primaryStage.show();
}