Nhờ câu trả lời của Sam và trang khác tôi tìm thấy ở nơi khác, tôi đã có thể giải quyết vấn đề này.
Tôi figured tôi chia sẻ giải pháp của tôi để các chàng tiếp theo không phải mảnh tất cả lại với nhau.
Tận hưởng!
import java.awt.Rectangle;
import java.awt.event.ComponentAdapter;
import java.awt.event.ComponentEvent;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import java.text.SimpleDateFormat;
import java.util.Date;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.JViewport;
import javax.swing.ScrollPaneConstants;
import javax.swing.SwingUtilities;
import javax.swing.table.DefaultTableModel;
/**
* Demonstrate displaying a specific cell in a JTable when a row is added.
* <p>
* The Table Row Index is displayed in one of the table's columns.
* <p>
* The cell containing the Value will be selected for displaying.
* <p>
* The specified cell will be made visible and, if possible, positioned in the center of the Viewport.
* <p>
* The code works regardless of:
* <ul>
* <li>Whether or not the table data is sorted</li>
* <li>The position/visibility of the "Value" column</li>
* </ul>
*/
public class JTableScrollToRow
{
static SecureRandom random;
private DefaultTableModel dtm;
static
{
try
{
random = SecureRandom.getInstance("SHA1PRNG");
int seed = Integer.parseInt((new SimpleDateFormat("SSS")).format(new Date()));
random.setSeed(random.generateSeed(seed));
}
catch (NoSuchAlgorithmException e)
{
e.printStackTrace();
}
}
public void buildGUI()
{
Object[][] data = {};
Object colNames[] = {
"Value",
"TableRowIx",
"Column A",
"Column B",
"Column C",
"Column D",
"Column E",
"Column F" };
dtm = new DefaultTableModel(data, colNames);
final JTable sampleTable = new JTable(dtm);
sampleTable.setDragEnabled(false);
sampleTable.setAutoCreateRowSorter(true);
// Turn off auto-resizing to allow for columns moved out of the Viewport
sampleTable.setAutoResizeMode(JTable.AUTO_RESIZE_OFF);
// Populate the table with some data
for (int x = 0; x < 200; x++)
{
addRow(x);
}
// Create a ScrollPane
JScrollPane sp = new JScrollPane(sampleTable);
// Provide a horizontal scroll bar so that columns can be scrolled out of the Viewport
sp.setHorizontalScrollBarPolicy(ScrollPaneConstants.HORIZONTAL_SCROLLBAR_ALWAYS);
final JFrame f = new JFrame();
f.getContentPane().add(sp);
f.setTitle("JTable cell display example");
f.pack();
f.setLocationRelativeTo(null);
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.setVisible(true);
// Create a thread that periodically adds a row to the table
Thread rowAdder = new Thread(new Runnable()
{
@Override
public void run()
{
do
{
try
{
int secs = 5;
Thread.sleep(secs * 1000);
}
catch (InterruptedException e)
{
e.printStackTrace();
}
// Add a row
addRow(dtm.getRowCount());
} while (true);
}
});
rowAdder.start();
// Add the custom ComponentListener
sampleTable.addComponentListener(new JTableCellDisplayer(sampleTable));
}
/**
* Display a table row when it is added to a JTable.<br>
* Details available at <a
* href="http://stackoverflow.com/questions/4890282/howto-to-scroll-to-last-row-on-jtable">StackOverflow</a>.
* <p>
* <b>Key information:</b> Whenever a row is added or removed the JTable resizes. This occurs even if the row is
* outside of the JScrollPane's Viewport (i.e., the row is not visible).
*/
class JTableCellDisplayer extends ComponentAdapter
{
boolean selRow = false;
boolean selCol = false;
boolean firstTime = true;
boolean selectData = false;
JTable table;
public JTableCellDisplayer(JTable jTable)
{
table = jTable;
}
@Override
public void componentResized(ComponentEvent e)
{
if (firstTime)
{
firstTime = false;
return;
}
int viewIx = table.convertRowIndexToView(table.getRowCount() - 1);
if (!selRow
&& !selCol)
{
System.out.println(" - Select nothing - selectData="
+ selectData);
}
else if (selRow
&& !selCol)
{
System.out.println(" - Select row only - selectData="
+ selectData);
}
else if (!selRow
&& selCol)
{
System.out.println(" - Select column only - selectData="
+ selectData);
}
else
{
System.out.println(" - Select cell - selectData="
+ selectData);
}
// If data should be selected, set the selection policies on the table.
if (selectData)
{
table.setRowSelectionAllowed(selRow);
table.setColumnSelectionAllowed(selCol);
}
// Scroll to the VALUE cell (columnIndex=0) that was added
displayTableCell(table, viewIx, table.convertColumnIndexToView(0), selectData);
// Cycle through all possibilities
if (!selRow
&& !selCol)
{
selRow = true;
}
else if (selRow
&& !selCol)
{
selRow = false;
selCol = true;
}
else if (!selRow
&& selCol)
{
selRow = true;
selCol = true;
}
else
{
selRow = false;
selCol = false;
selectData = !selectData;
}
}
}
/**
* Assuming the table is contained in a JScrollPane, scroll to the cell (vRowIndex, vColIndex). <br>
* The specified cell is guaranteed to be made visible.<br>
* Every attempt will be made to position the cell in the center of the Viewport. <b>Note:</b> This may not be
* possible if the row is too close to the top or bottom of the Viewport.
* <p>
* It is possible to select the specified cell. The amount of data selected (none, entire row, entire column or a
* single cell) is dependent on the settings specified by {@link JTable#setColumnSelectionAllowed(boolean)} and
* {@link JTable#setRowSelectionAllowed(boolean)}.
* <p>
* Original code found <a href="http://www.exampledepot.com/egs/javax.swing.table/VisCenter.html">here</a>.
* <p>
*
* @param table
* - The table
* @param vRowIndex
* - The view row index
* @param vColIndex
* - The view column index
* @param selectCell
* - If <code>true</code>, the cell will be selected in accordance with the table's selection policy;
* otherwise the selected data will not be changed.
* @see JTable#convertRowIndexToView(int)
* @see JTable#convertColumnIndexToView(int)
*/
public static void displayTableCell(JTable table, int vRowIndex, int vColIndex, boolean selectCell)
{
if (!(table.getParent() instanceof JViewport))
{
return;
}
JViewport viewport = (JViewport) table.getParent();
/* This rectangle is relative to the table where the
* northwest corner of cell (0,0) is always (0,0).
*/
Rectangle rect = table.getCellRect(vRowIndex, vColIndex, true);
// The location of the view relative to the table
Rectangle viewRect = viewport.getViewRect();
/*
* Translate the cell location so that it is relative
* to the view, assuming the northwest corner of the
* view is (0,0).
*/
rect.setLocation(rect.x
- viewRect.x, rect.y
- viewRect.y);
// Calculate location of rectangle if it were at the center of view
int centerX = (viewRect.width - rect.width)/2;
int centerY = (viewRect.height - rect.height)/2;
/*
* Fake the location of the cell so that scrollRectToVisible
* will move the cell to the center
*/
if (rect.x < centerX)
{
centerX = -centerX;
}
if (rect.y < centerY)
{
centerY = -centerY;
}
rect.translate(centerX, centerY);
// If desired and allowed, select the appropriate cell
if (selectCell
&& (table.getRowSelectionAllowed() || table.getColumnSelectionAllowed()))
{
// Clear any previous selection
table.clearSelection();
table.setRowSelectionInterval(vRowIndex, vRowIndex);
table.setColumnSelectionInterval(vColIndex, vColIndex);
}
// Scroll the area into view.
viewport.scrollRectToVisible(rect);
}
private String addRow(int tableRowIndex)
{
String retVal;
int value = random.nextInt(99999999);
dtm.addRow(new Object[] {
value,
tableRowIndex,
random.nextInt(99999999),
random.nextInt(99999999),
random.nextInt(99999999),
random.nextInt(99999999),
random.nextInt(99999999),
random.nextInt(99999999), });
retVal = "Row added - value="
+ value + " & tableRowIx=" + tableRowIndex;
System.out.println(retVal);
return retVal;
}
public static void main(String[] args)
{
SwingUtilities.invokeLater(new Runnable()
{
@Override
public void run()
{
new JTableScrollToRow().buildGUI();
}
});
}
}
vui mừng bạn đã tìm thấy một giải pháp :-) Tò mò mặc dù: chưa bao giờ thấy một bối cảnh nơi gói các scrollRectToVisible vào invokeLater đã không làm việc - bạn sẽ xem xét để hiển thị một sscce nơi này đã xảy ra? – kleopatra
thực sự cảm ơn bạn, nó rõ ràng là một thiết kế xấu trong swing, họ nên sửa chữa nó – AvrDragon
@AvrDragon không có gì sai với thiết kế ... nó chỉ là chờ đợi cho đến khi-the-internals thông thường được cập nhật. Điều thường được thực hiện trong một invokeLater, như đã được đề cập trong bình luận cuối cùng của tôi. – kleopatra