Problem with inserting rows into JTable

Question

Hello people.

I have problems on inserting rows into a JTable and I don't know what the problem is.

I do exactly like this:

((DefaultTableModel)myJTable.getModel()).insertRow(0,webSiteDownloader.getWebSites().toArray());

The webSiteDownloader is one object that have an ArrayList. I can get that array calling the method getWebSites.

The problem is that when I insert one row, adding the second one, the JTbable only shows the first one, but repeated twice. Was I clear enough?

Thks :D

Answer 1

I'll take a shot into the dark and guess that you want to accomplish something like this:

DefaultTableModel dtm = (DefaultTableModel)myJTable.getModel();
for (MyRowObject row : webSiteDownloader.getWebSites()) {
  dtm.insertRow(0, row.toArray());
}

Is there a special reason that you're using insertRow instead of addRow?

Also, I'd really like to recommend that you roll your own special purpose TableModel by extending AbstractTableModel. Basic untested example:

public class MyTableModel extends AbstractTableModel
{
  protected List<MyObject> rows;

  public MyTableModel()
  {
    rows = new ArrayList<MyObject>();
  }

  public void add(MyObject obj)
  {
    rows.add(obj);
  }

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

  @Override
  public int getColumnCount()
  {
    // This value will be constant, but generally you'd also
    // want to override getColumnName to return column names
    // from an array, and in that case you can return the length
    // of the array with column names instead
    return 2;
  }

  @Override
  public Object getValueAt(int row, int column)
  {
    MyObject obj = rows.get(row);

    // Change this to match your columns
    switch(column) {
      case 0: return obj.getId();
      case 1: return obj.getName();
    }

    return null;
  }
}