AbstractTableModel contains proper data but will not update on fireTablDataChanged

问题

I've searched and seen this question multiple times, and none of the solutions work.

I have an AbstractTableModel that I've extended and called AccountTableModel. The code is as such.

import InvAcntItem.Account;
import java.util.LinkedList;
import javax.swing.table.AbstractTableModel;

public class AccountTableModel extends AbstractTableModel 
{
    LinkedList<Account> dataList;
    private String[] columnNames = {"Username", "Password"};

    public AccountTableModel()
    {
        dataList = new LinkedList<>();
    }

    public void setNewAccounts(LinkedList<Account> inAccs)
    {
        System.out.println("Syncing local account");
        LinkedList<Account> newList = new LinkedList<>();
        for(int i = 0; i < inAccs.size(); i++)
            newList.add(Account.getDeepCopy(inAccs.get(i)));
        System.out.println("done");
        this.dataList = newList;
        System.out.println("set");
        this.fireTableDataChanged();
        System.out.println("set");
    }

    @Override
    public int getRowCount() 
    {
        return dataList.size();
    }

    @Override
    public int getColumnCount() 
    {
        return columnNames.length;
    }

    @Override
    public Object getValueAt(int col, int row) 
    {
        System.out.println("GetValueAt!");
        Object retObj = null;
        Account rowAcc = dataList.get(row);
        switch(col)
        {
            case 0:
            {
                retObj = rowAcc.user;
            }
            break;
            case 1:
            {
                retObj = rowAcc.pass;
            }
            break;
        }
        return retObj;
    }
}

All of the println statements are executed, yet the UI never updates. I have even gone so far as to create a button that when clicked calls the table models fireDataChanged function.

It also calls the getValueAt function and returns good data.

Is there anything else that would keep a table from redrawing?

回答1:

Among other things, your implementation of getValueAt() has the row and column interchanged. Fixing that and adding fake Account data seems to work.

import java.awt.EventQueue;
import java.util.LinkedList;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.table.AbstractTableModel;

/**
 * @see http://stackoverflow.com/a/25736893/230513
 */
public class Test {

    private static class Account {

        public Account() {
        }
    }

    class AccountTableModel extends AbstractTableModel {

        LinkedList<Account> dataList = new LinkedList<>();
        private String[] columnNames = {"Username", "Password"};

        public void setNewAccounts(LinkedList<Account> inAccs) {
            dataList.clear();
            dataList.addAll(inAccs);
            this.fireTableDataChanged();
        }

        @Override
        public int getRowCount() {
            return dataList.size();
        }

        @Override
        public int getColumnCount() {
            return columnNames.length;
        }

        @Override
        public Object getValueAt(int row, int col) {
            Account account = dataList.get(row);
            if (col == 0) {
                return account.getClass();
            }
            if (col == 1) {
                return account.hashCode();
            }
            return null;
        }
    }

    private void display() {
        JFrame f = new JFrame("Test");
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        AccountTableModel model = new AccountTableModel();
        LinkedList<Account> list = new LinkedList<>();
        list.add(new Account());
        list.add(new Account());
        list.add(new Account());
        model.setNewAccounts(list);
        f.add(new JScrollPane(new JTable(model)));
        f.pack();
        f.setLocationRelativeTo(null);
        f.setVisible(true);
    }

    public static void main(String[] args) {
        EventQueue.invokeLater(() -> {
            new Test().display();
        });
    }
}

来源：https://stackoverflow.com/questions/25736443/abstracttablemodel-contains-proper-data-but-will-not-update-on-firetabldatachang

标签

java

swing

jtable

abstracttablemodel