java - GlazedList 更新 JTable 中的 EventList

Question

如何更新 EventList 列表来更新 JTable？这就是我所做的:

        String[] headers = new String[]{"MNO", "NAME", "ID/REG No", "PHONE"};
        String[] properties = new String[]{"milkNo", "fullName", "nationalId", "phone1"};


        TextFilterator<Member> personTextFilterator = new TextFilterator<Member>() {

            @Override
            public void getFilterStrings(List list, Member m) {
                list.add(m.getFullName());
                list.add(m.getMilkNo());
                list.add(m.getNationalId());
                list.add(m.getPhone1());
            }
        };

        MatcherEditor<Member> textMatcherEditor = new TextComponentMatcherEditor<Member>(txtFilter, personTextFilterator);

        FilterList<Member> filterList = new FilterList<Member>(eventList, textMatcherEditor);

        TableFormat tf = GlazedLists.tableFormat(properties, headers);
        model = new EventTableModel<Member>(filterList, tf);

        selectionModel = new EventSelectionModel<Member>(filterList);
        tblMembers.setSelectionModel(selectionModel);

        tblMembers.setModel(model);

问题是当我过滤表中的记录并选择一条记录并尝试更新它时，它会在表中创建一条新记录

int updatedRow = tblMembers.convertRowIndexToModel(tblMembers.getSelectedRow());
eventList.set(updatedRow, updatedMember);

Answer 1

一旦您使用 GlazedLists 为您的 JTable 提供支持，那么您应该只使用 EventTableModel 和 EventSelectionModel 与您的 JTable 交互。您所犯的错误是直接在 JTable 中查询所选行并获取其索引 - 但 JTable 不明白它是由可能对其中的项目进行排序/过滤的 EventList 支持的。因此，JTable 中的行 i 不一定对应于 EventList 中的元素 i。

在您的代码中，您实际上已经设置了一个 EventSelectionModel，现在只需使用它即可。

if (!selectionModel.isSelectionEmpty()) {
    EventList<Member> selectedMembers = selectionModel.getSelected();
    for (int i = 0; i<selectedMembers.size(); i++) {
        Member member = selectedMembers.get(i);
        //update accordingly...
        //member.setXXX(...); 
        selectedMembers.set(i, member);
     }
}

您必须记住，JTable 支持多行选择(尽管可以配置为仅允许单行选择)，因此 EventSelectionModel 会明智地返回所有选定行的 EventList，即使只选择了一行。因此，您需要迭代返回的列表。还有一个额外的便利，即包含所选项目的 EventList 由源 EventList 支持，因此您可以直接对该子列表进行更改。

高级

当然，事件列表非常适合观察列表的基本变化:删除、插入、更新(即用另一个对象替换索引i处的现有对象)。但是，如果我们可以直接更新 EventList 中的对象，然后让 GlazedLists 检测该属性更改，而不是调用 selectedMembers.set()，不是很好吗？

嗯，这也是可能的。有一个名为 ObservableElementList 的有用列表类型，它将监听其包含的每个对象的属性更改并相应地刷新。这比必须在列表中找到对象并调用 eventList.set() 方便得多。

您首先需要使您的类支持属性监听器，即是一个正确的 Java bean，然后使用 ObservableElementList.Connector。

我已经创建了一个小而完整的示例。在此示例中，顶部有一个用于过滤的文本输入，一个包含简短作者列表的表格，以及底部的一个按钮，用于更新任何选定行的名称。

import ca.odell.glazedlists.BasicEventList;
import ca.odell.glazedlists.EventList;
import ca.odell.glazedlists.FilterList;
import ca.odell.glazedlists.GlazedLists;
import ca.odell.glazedlists.ObservableElementList;
import ca.odell.glazedlists.TextFilterator;
import ca.odell.glazedlists.matchers.MatcherEditor;
import ca.odell.glazedlists.swing.EventSelectionModel;
import ca.odell.glazedlists.swing.EventTableModel;
import ca.odell.glazedlists.swing.TextComponentMatcherEditor;
import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.beans.PropertyChangeListener;
import java.beans.PropertyChangeSupport;
import java.util.List;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.JTextField;

public class GlazedListSelectionObservable {

    private JFrame frame;
    private JTable table;
    private JTextField txtInput;

    private EventList<Person> people;
    private EventSelectionModel<Person> selectionModel;

    public GlazedListSelectionObservable() {

        setupGui();
        setupGlazedLists();
        populatedList();
        frame.setVisible(true);
    }

    private void setupGui() {

        frame = new JFrame("GlazedLists Selection Example");
        frame.setSize(600, 600);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        txtInput = new JTextField();
        table = new JTable();
        frame.getContentPane().add(new JScrollPane(table), BorderLayout.CENTER);

        JButton updateTableButton = new JButton("Update selected row");

        updateTableButton.addActionListener(new ActionListener() {

            @Override
            public void actionPerformed(ActionEvent e) {
                if (!selectionModel.isSelectionEmpty()) {
                    EventList<Person> selectedPeople = selectionModel.getSelected();
                    for (Person person: selectedPeople) {
                        person.setFirstName("David");
                        person.setLastName("Baldacci");
                    }
                }
            }
        });

        frame.getContentPane().add(txtInput, BorderLayout.NORTH);
        frame.getContentPane().add(updateTableButton, BorderLayout.SOUTH);

    }

    private void populatedList() {
        people.add(new Person("John", "Grisham"));
        people.add(new Person("Patricia", "Cornwell"));
        people.add(new Person("Nicholas", "Sparks"));
        people.add(new Person("Andy", "Weir"));
        people.add(new Person("Elizabeth", "George"));        
    }

    private void setupGlazedLists() {
        people = new BasicEventList<Person>();
        MatcherEditor<Person> textMatcherEditor = new TextComponentMatcherEditor<Person>(txtInput, new PersonTextFilterator());

        ObservableElementList.Connector<Person> personConnector = GlazedLists.beanConnector(Person.class);
        EventList<Person> observedPeople = new ObservableElementList<Person>(people, personConnector);

        FilterList<Person> filteredPeople = new FilterList<Person>(observedPeople, textMatcherEditor);

        EventTableModel model = new EventTableModel(filteredPeople, GlazedLists.tableFormat(new String[]{"firstName", "lastName"} , new String[]{"First Name", "Last Name"}));

        selectionModel = new EventSelectionModel<Person>(filteredPeople);

        table.setModel(model);
        table.setSelectionModel(selectionModel);
    }

    class PersonTextFilterator implements TextFilterator<Person> {

        @Override
        public void getFilterStrings(List<String> list, Person person) {
            list.add(person.getFirstName());
            list.add(person.getLastName());
        }

    }

    public class Person {

        private String firstName;
        private String lastName;

        private final PropertyChangeSupport support = new PropertyChangeSupport(this);

        public Person() {
        }

        public Person(String firstName, String lastName) {
            this.firstName = firstName;
            this.lastName = lastName;
        }

        public String getFirstName() {
            return firstName;
        }

        public String getLastName() {
            return lastName;
        }

        public void setFirstName(String firstName) {
            final String oldFirstName = this.firstName;
            this.firstName = firstName;
            support.firePropertyChange("firstName", oldFirstName, firstName);
        }

        public void setLastName(String lastName) {
            final String oldLastName = this.lastName;
            this.lastName = lastName;
            support.firePropertyChange("lastName", oldLastName, lastName);
        }

        public void addPropertyChangeListener(PropertyChangeListener l) {
            support.addPropertyChangeListener(l);
        }

        public void removePropertyChangeListener(PropertyChangeListener l) {
            support.removePropertyChangeListener(l);
        }

    }

    public static void main(String[] args) {
        javax.swing.SwingUtilities.invokeLater(new Runnable() {
            @Override
            public void run() {
              new GlazedListSelectionObservable();
            }
        });
    }

}