Name: el35337 Date: 05/29/98


The following source illustrates the problem:
(0)Basic problem - list selection is triggered
by mousePressed, not mouseReleased...and so...
(1) attach a ListSelectionListener to JTable
(2) Have the listener fire a JDialog.
(3) The mouse click on the JTable will fire the
dialog.
(4) The dialog will trap the mouse-release event
which resets the 'phantom mouse' flag on JTable
(5) SO the NEXT mouse click on the JTable will
be ignored.
CODE-----------------------------------------------
CODE-----------------------------------------------
CODE-----------------------------------------------
package test;
import java.awt.*;
import java.awt.event.*;
import com.sun.java.swing.*;
import com.sun.java.swing.event.*;
import com.sun.java.swing.table.*;
import tablelayout.*;

/**
 * This demonstrates the bug in the JTable's ignoring of 'phantom'
 * mouse events - the problem is that the flag to pay attention
 * to mouse events is only reset by the mouseReleased event. The table may
 * never receive this event if its ListSelectionListener fires
 * up a dialog (a plausible situation). <BR>
 * How quickly you release the mouse when you select a row
 * in this code's table will determine whether the NEXT click of
 * a row does anything.
 * <P>
 * NOTE - when you click a row you will receive TWO dialogs in a row.
 * -- ignore that - it's not the point - the point is that after
 * the dialogs have been disposed of, the NEXT mouse click back on
 * the table probably wont have any effect because the 'phantom mouse'
 * flag hasnt been reset. You can see that the table is not even
 * being messaged about the selection because there's no output
 * from the System.out.println statement in the valueChanged method.
 *
 * @author vivek iyer ###@###.### 5-27-98
**/
public class
TableTest
extends
JPanel
implements
ListSelectionListener
{
public TableTest(){
TableModel dataModel =
new AbstractTableModel() {
public int getColumnCount() { return 10; }
public int getRowCount() { return 10;}
public Object getValueAt(int row, int col) { return new Integer(row*col);
}
};

JTable table = new JTable(dataModel);

//
//set up a list selection listener to launch a dialog
//when the user clicks on a row.
table.getSelectionModel().addListSelectionListener (this);

JScrollPane scrollpane = JTable.createScrollPaneForTable(table);
add(scrollpane);

JFrame theFrame = new JFrame("Test");
theFrame.getContentPane().add("Center",this);
theFrame.pack();
theFrame.show();
theFrame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
}//end TableTest()

public static void main (String[] args){
TableTest test = new TableTest();
}

//
//We listen to the user clicking on a table row.
public void valueChanged(ListSelectionEvent e){
System.out.println("value Changed Fired On Table");
JOptionPane.showMessageDialog(
null,
"row clicked - you will receive two of these dialogs for every row click",
"row clicked",
JOptionPane.INFORMATION_MESSAGE
);
}//end valueChanged
}
(Review ID: 32464)
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