added some utilities for tables

git-svn-id: http://repo.nplusc.de/svn/iZink@187 8b19561d-0d00-6744-8ac1-9afc8f58a8aa

ToolKit/src/de/nplusc/izc/tools/UiToolz/TableCellListener.java

@@ -0,0 +1,171 @@
+package de.nplusc.izc.tools.UiToolz;
+
+import java.awt.event.*;
+import javax.swing.*;
+import java.beans.*;
+
+/*
+ *  This class listens for changes made to the data in the table via the
+ *  TableCellEditor. When editing is started, the value of the cell is saved
+ *  When editing is stopped the new value is saved. When the oold and new
+ *  values are different, then the provided Action is invoked.
+ *
+ *  The source of the Action is a TableCellListener instance.
+ *  gotten from: http://tips4java.wordpress.com/2009/06/07/table-cell-listener/
+ */
+public class TableCellListener implements PropertyChangeListener, Runnable
+{
+	private JTable table;
+	private Action action;
+
+	private int row;
+	private int column;
+	private Object oldValue;
+	private Object newValue;
+
+	/**
+	 *  Create a TableCellListener.
+	 *
+	 *  @param table   the table to be monitored for data changes
+	 *  @param action  the Action to invoke when cell data is changed
+	 */
+	public TableCellListener(JTable table, Action action)
+	{
+		this.table = table;
+		this.action = action;
+		this.table.addPropertyChangeListener( this );
+	}
+
+	/**
+	 *  Create a TableCellListener with a copy of all the data relevant to
+	 *  the change of data for a given cell.
+	 *
+	 *  @param row  the row of the changed cell
+	 *  @param column  the column of the changed cell
+	 *  @param oldValue  the old data of the changed cell
+	 *  @param newValue  the new data of the changed cell
+	 */
+	private TableCellListener(JTable table, int row, int column, Object oldValue, Object newValue)
+	{
+		this.table = table;
+		this.row = row;
+		this.column = column;
+		this.oldValue = oldValue;
+		this.newValue = newValue;
+	}
+
+	/**
+	 *  Get the column that was last edited
+	 *
+	 *  @return the column that was edited
+	 */
+	public int getColumn()
+	{
+		return column;
+	}
+
+	/**
+	 *  Get the new value in the cell
+	 *
+	 *  @return the new value in the cell
+	 */
+	public Object getNewValue()
+	{
+		return newValue;
+	}
+
+	/**
+	 *  Get the old value of the cell
+	 *
+	 *  @return the old value of the cell
+	 */
+	public Object getOldValue()
+	{
+		return oldValue;
+	}
+
+	/**
+	 *  Get the row that was last edited
+	 *
+	 *  @return the row that was edited
+	 */
+	public int getRow()
+	{
+		return row;
+	}
+
+	/**
+	 *  Get the table of the cell that was changed
+	 *
+	 *  @return the table of the cell that was changed
+	 */
+	public JTable getTable()
+	{
+		return table;
+	}
+//
+//  Implement the PropertyChangeListener interface
+//
+	@Override
+	public void propertyChange(PropertyChangeEvent e)
+	{
+		//  A cell has started/stopped editing
+
+		if ("tableCellEditor".equals(e.getPropertyName()))
+		{
+			if (table.isEditing())
+				processEditingStarted();
+			else
+				processEditingStopped();
+		}
+	}
+
+	/*
+	 *  Save information of the cell about to be edited
+	 */
+	private void processEditingStarted()
+	{
+		//  The invokeLater is necessary because the editing row and editing
+		//  column of the table have not been set when the "tableCellEditor"
+		//  PropertyChangeEvent is fired.
+		//  This results in the "run" method being invoked
+
+		SwingUtilities.invokeLater( this );
+	}
+	/*
+	 *  See above.
+	 */
+	@Override
+	public void run()
+	{
+		row = table.convertRowIndexToModel( table.getEditingRow() );
+		column = table.convertColumnIndexToModel( table.getEditingColumn() );
+		oldValue = table.getModel().getValueAt(row, column);
+		newValue = null;
+	}
+
+	/*
+	 *	Update the Cell history when necessary
+	 */
+	private void processEditingStopped()
+	{
+		newValue = table.getModel().getValueAt(row, column);
+
+		//  The data has changed, invoke the supplied Action
+
+		if (! newValue.equals(oldValue))
+		{
+			//  Make a copy of the data in case another cell starts editing
+			//  while processing this change
+
+			TableCellListener tcl = new TableCellListener(
+				getTable(), getRow(), getColumn(), getOldValue(), getNewValue());
+
+			ActionEvent event = new ActionEvent(
+				tcl,
+				ActionEvent.ACTION_PERFORMED,
+				"");
+			action.actionPerformed(event);
+		}
+	}
+}