java pass data to JTable's row upon button click

问题

I'm doing a java app which has to pass an initialized array of string to display as a row to a JTable.

This is what I tried:

      Object[] _row1;

      public PrintMeNow() {
            table = new JTable();
    table.setBounds(16, 203, 362, 16);
    table.setShowHorizontalLines(true);
    table.setShowVerticalLines(true);
    table.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
    table.setModel(new DefaultTableModel(
        new Object[][] {
                _row1, {2,2,2}, {3,3,3}, {4,4,4}
        },
        new String[] {
            "QTY", "Item Code", "Amount"
        }
    ));

     }

  btnStart.addActionListener(new ActionListener() {
  public void actionPerformed(ActionEvent arg0) {
           _row1 = new Object[]{"DN Korina", "DN Madrid", "DN Romania"};
      }
  });

But when I pressed the start button, it's not filling the row. What am I doing wrong in here? Help is much appreciated. Thanks.

回答1:

What you need to do is add a row to the Model. Something like this

public void actionPerformed(ActionEvent arg0) {
    DefaultTableModel model = (DefaultTableModel)table.getModel();
    model.addRow(new Object[]{"DN Korina", "DN Madrid", "DN Romania"});
}

The easiest way is to set up you model before hand to have no rows

String[] colNames = {
       "QTY", "Item Code", "Amount"
};

DefaultTableModel model = new DefaultTableModel(colNames, 0);  <== 0 rows
JTable table = new JTable(model);

Then whatever rows you want to add, just add to the model

public void actionPerformed(ActionEvent e){
    model.addRow(new Object[]{"DN Korina", "DN Madrid", "DN Romania"});
}

UPDATE Example

import java.awt.*;
import java.util.Stack;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.table.DefaultTableModel;

public class TestTable {

    private String[] colNames = { "Col 1", "Col2", "Col3", "Col4", "Col5" };

    private DefaultTableModel model = new DefaultTableModel(colNames, 0);
    private JTable table = new JTable(model);
    private MyStack myStack = new MyStack();
    private Stack<Integer[]> stack;

    private JButton button = new JButton("Add Row");

    public TestTable() {
        stack = myStack.getStack();

        button.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                if (!stack.isEmpty()) {
                    Integer[] array = stack.pop();
                    model.addRow(array);
                }
            }
        });

        JFrame frame = new JFrame();
        frame.add(new JScrollPane(table), BorderLayout.CENTER);
        frame.add(button, BorderLayout.SOUTH);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.pack();
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                new TestTable();
            }
        });
    }
}

class MyStack {
    public Stack<Integer[]> stack = new Stack<Integer[]>();

    public MyStack() {
        int k = 1;
        for (int i = 0; i < 20; i++) {
            Integer[] array = new Integer[5];
            for (int j = 0; j < 5; j++) {
                array[j] = i * k * (j + 1);
            }
            k++;
            stack.push(array);
        }
    }

    public Stack<Integer[]> getStack() {
        return stack;
    }
}

Explanation

I have a MyStack class that has a Stack. It could be any data structure like an array even, but I chose to use a Stack because I can just .pop() it. And the get the Integer[].
I instantiate that class in the GUI class
I then extract that Stack. Keep in mind the Stack holds Integer[]'s
As i explained, you want to add a single dimension array to the model.
So every time I click the button, an Integer[] is pulled out of the Stack, then I just add that array to the model as a row.

回答2:

But when I pressed the start button, it's not filling the row. What am I doing wrong in here?

your code inside ActionListener missing any code to addRow to JTable or to DefaultTableModel (table.getModel....)
in the case that you are using DefaultTableModel doesn't matter if is row added to JTable or DefaultTableModel
don't to use NullLayout in Swing, Swing is designated to be laid by using LayoutManager

来源：https://stackoverflow.com/questions/20967741/java-pass-data-to-jtables-row-upon-button-click

标签

java

swing

jtable