Dynamically resize JTable cell to fit a JList

Hi!
I've been banging my head trying to add some dynamic behavior to a TableCellEditor. In short I'm trying trying to make it resize the height of the current row (the one it is in) to reflect the changes made to the JList used to let the user edit the cells value (which is a list of items).
I've come across some threads dealing with the problem of resizing a cell to fit its content. This however is usually only done once (in the 'getTableCellEditorComponent' function) and so only provides half the answer. Also, since the editor is only active during cell editing I've been trying to make it revert to the old cell height after the editing is done.
So far I have not come up with any decent solution to this problem and was hoping someone out there might have an idea or have read something similar and can point me to something helpful... anyone?
Cheers!
Teo

The Swing tutorial on[url http://java.sun.com/docs/books/tutorial/uiswing/components/table.html]How to Use Tables shows how to dynamically change the size to Table Columns.
If you need help calculating the acutal size then try searching the forum. Using keywords "resize jtable column" (keywords I took directly from your topic title) I found some promising postings.

Similar Messages

How to resizea JTable column to fit to text programatically?

hi evreyone,
i'm trying to resize a JTable column width to fit to the contained text programatically.my approach was that i made a comparison between the length of String objects contained in my column and got the biggest String length value but i want to know how can i resize the column to fit to this biggest String object

You're going the wrong way about it - don't go calculating string lengths. Get the TableCellRenderer, query it for the renderer component for each cell in the column, obtain its preferred size and keep a record of the greatest width value.

Can JTable cell acts as JList?

I was planning to create an Event Calendar view in Monthly. Currently my jTable cell extends JTextArea. My problem is that, for example, today I got 2 events display in one cell, when a user double-click the "today" cell, an edit form will pop out, if there are 2 events in one cell, how I know which events to be edit? In this case I was thinking to use JList instaed of jTextArea. so i can choose which event to be edit. Is there any example showing how to implement jTable with jList cell? or is there any other method to overcome it?

I haven't used a JList in a JTable so far, but for a JComboBox you find a working example in the tutorial. That may give you some ideas.
What I did use is a (read only) JTable in a JTable. So if you don't achieve your goal with JList there are alternatives.
But wait for our table specialists to come along.

Resizing the JTable Cell horizontal width

Sir/Madam,
How can i resize the JTable cell's horizontal width. I know the JTable's column width can be resized. I dont want to resize the entire JTable column. But i need to resize individual JTable cell's horizontal width. Thanks in advance.

I think that's not possible. What kind of results are you expecting ? If the cells of a column are different widths, what are you going to do with the extra space of the narrower cells ?
What are you displaying in the cells ? Maybe you can narrow the contents of the cells, and not the cells.

Dynamic colored in theh JTable cell

Hi, All
I am using a JTable to display a Jlable in the JTable cells.
The lable is divided to, say 10 , sub rectangles. I would liketo fill each rectangles with different bg colors depending on the data I received. I tried to use html in the JLable to control the color, however, it is very expensive cuase it involves a lot of string process and also it is difficult to control the dimension of those rectangles. Do anyone has any better idea to do this ?
The cell is not necessary to be a JLable, by the way.
Thanks in advance !

I have never used JPanel as my table cell component, but u might want to implement performance improvements similiar to ones done in DefaultTableCellRenderer which extends JLabel.
Here is the code extract from DefaultTableCellRenderer
* The following methods are overridden as a performance measure to
* to prune code-paths are often called in the case of renders
* but which we know are unnecessary. Great care should be taken
* when writing your own renderer to weigh the benefits and
* drawbacks of overriding methods like these.
* Overridden for performance reasons.
* See the Implementation Note
* for more information.
public void validate() {}
* Overridden for performance reasons.
* See the Implementation Note
* for more information.
public void revalidate() {}
* Overridden for performance reasons.
* See the Implementation Note
* for more information.
public void repaint(long tm, int x, int y, int width, int height) {}
* Overridden for performance reasons.
* See the Implementation Note
* for more information.
public void repaint(Rectangle r) { }

How do I stop iPhone Safari from dynamically resizing the visual viewport?

Sorry I post this here, but I couldn't access the developer forums (no error given, it just keeps returning me to this page https://developer.apple.com/devforums/) I'm not even sure wether that's been moved here and it's just the redirection non working.
I need to Stop iPhone Safari from dynamically resizing the visual viewport, or in other words, to stop it from trying to "fit" the layout into the viewport.
Why?
Because any recalculation javascript does on absolutely positioned elements makes the whole site super IRRESPONSIVE.
I don't know wether the issue is the element going out the already-set layout viewport (which triggers the page resizing to fit the visual viewport) or just the calculations being made constantly, but I can stop the calculations from happening when not "touching" the screen, but I need a way to stop the page resizing.
I tried setting the viewport width to 1040px, as my layout width, and it fixed the header's width being narrower than the body (or shifted left?), but the whole page is still resized with every motion-frame (one every 3 seconds, due to overloading the redrawing engine)
Is there a way to prevent that?

No, that link doesn't solve it. It just says the same is found everywhere online.
There's probably no way to do it, as per their way they "accidentally" omitted the oposite case: the page being wider than 980. They only mention what to do if the site is narrower. Something I learned is big companies (with reputation management) could let you run in circles for years no answer rather than telling you something is not possible.
I'm the developer (can't access the dev forums, don't know why) and I DID setup the viewport, scale and other properties but none of them stopped from re-fitting the new re-sized layout in the viewport. They just ensure the "initial" view.
I think the feature I'm looking for must be achieved with some JavaScript function targeting Safari-proprietary variable/property… if even possible.
I just had to make things never reaching the edge until somebody contributes something useful

Custom JTable cell editors and persistence

I have a JTable with an underlying data model (an extension of AbstractTableModel) that uses custom cell editors in the last column. The cell editor in that column, for a given row, depends on the value selected in another column of the same row. The cell editors include text, date, list, and tree editors (the last one in a separate dialogue). The number of rows is changeable.
I have need to persist the data for a populated table from time to time, for restoration later on. I've achieved that, such that the data model is recreated, the table appears correct, and the appropriate cell editors activated (by creating new instances of the editors' classes).
However, my problem is that the (custom) cell editors do not reflect the data in the model when editing mode is begun the first time after restoration. Eg. the text editor is always empty, the list editor shows the first item, and no node is selected in the tree editor.
If I've restored the model correctly, should the editors properly reflect the underlying data when they are set to editing mode?
I suspected not, and thus tried to explicitly 'set' the correct values immediately after each editor is recreated ... but to no avail.
Does anyone have any thoughts, or experience with something similar? I'm happy to supply code.

You can use html tags within Swing, so I think you can do the following:
* MyRenderer.java
* Created on 26 April 2007, 10:27
* To change this template, choose Tools | Template Manager
* and open the template in the editor.
package newpackage;
import java.awt.Component;
import javax.swing.JLabel;
import javax.swing.JTable;
import javax.swing.SwingConstants;
import javax.swing.table.TableCellRenderer;
* @author CS781RJ
public class MyRenderer extends JLabel implements TableCellRenderer
    public MyRenderer()
        setHorizontalTextPosition(SwingConstants.RIGHT);
        setIconTextGap(3);
        setOpaque(true);
    public Component getTableCellRendererComponent(JTable table, Object value, boolean isSelected, boolean cellHasFocus, int row, int column)
        if (isSelected)
            setBackground(table.getSelectionBackground());
            setForeground(table.getSelectionForeground());
        else
            setBackground(table.getBackground());
            setForeground(table.getForeground());
        if (value instanceof String)
            if ((value != null) && (value.toString().length() > 0))
                System.out.println("Value: " + value.toString());
                setFont(new java.awt.Font("Tahoma", 0, 11));
                setText("<html>" + value.toString().replaceAll("\n", "<br>") + "</html>");
        return this;
}In the class that has the JTable, use the code AFTER declaring the values, columns, etc:
jTable1.getColumnModel().getColumn(0).setCellRenderer(new MyRenderer());
jTable1.setValueAt("Riz\nJavaid", 0, 0);One thing I haven't done is to resize the cell heights, make sure this is done.
Hope this helps
Riz

Dynamically resizing DefaultMutableTreeNode

Does anyone know how to resize a DefaultMutableTreeNode after it's been created and initially sized? I have a tree that can be resized, but if I dynamically resize it so that some nodes are wider than the tree, I'd like the last few visible characters within the nodes to be replaced by three dots "..." instead of just clipping the text. The JTable does this when you resize a column.
Thanks,
Steve Sinai

I change the two lines below:
1. This: textField.text = val        to this: textField.htmlText = val;
2. This: return textField.text;     to this: return textField.htmlText;
Here we go:
import flash.events.Event;
import flash.text.StyleSheet;
import mx.controls.TextArea;
public class DynamicTextArea extends TextArea
   public function DynamicTextArea(){
      super();
      super.horizontalScrollPolicy = "off";
      super.verticalScrollPolicy = "off";
      this.addEventListener(Event.CHANGE, adjustHeightHandler);
    private function adjustHeightHandler(event:Event):void{
      //trace("textField.getLineMetrics(0).height: " + textField.getLineMetrics(0).height);
      if(height <= textField.textHeight + textField.getLineMetrics(0).height){
        height = textField.textHeight;
        validateNow();
    override public function set htmlText(val:String):void{
      textField.htmlText = val;
      validateNow();
      height = textField.textHeight;
      validateNow();
    override public function set height(value:Number):void{
      if(textField == null){
        if(height <= value){
          super.height = value;
      }else{
        var currentHeight:uint = textField.textHeight + textField.getLineMetrics(0).height;
        if (currentHeight<= super.maxHeight){
          if(textField.textHeight != textField.getLineMetrics(0).height){
            super.height = currentHeight;
        }else{
            super.height = super.maxHeight;
    override public function get htmlText():String{
        return textField.htmlText;
    override public function set maxHeight(value:Number):void{
      super.maxHeight = value;

Can not show the JCheckBox in JTable cell

I want to place a JCheckBox in one JTable cell, i do as below:
i want the column "d" be a check box which indicates "true" or "false".
String[] columnNames = {"a","b","c","d"};
Object[][] rowData = {{"", "", "", Boolean.FALSE}};
tableModel = new DefaultTableModel(rowData, columnNames);
dataTable = new JTable(tableModel);
dataTable.getColumnModel().getColumn(3).setCellEditor(new DefaultCellEditor(new JCheckBox()));
But when i run it, the "d" column show the string "false" or "true", not the check box i wanted.
I do not understand it, can you help me?
Thank you very much!
coral9527

Do not use DefaultTableModel, create your own table model and you should implement the method
getColumnClass to display the boolean as checkbox ...
I hope the following colde snippet helps you :
class MyModel extends AbstractTableModel {
          private String[] columnNames = {"c1",
"c2"};
public Object[][] data ={{Boolean.valueOf(true),"c1d1"}};
     public int getColumnCount() {
     //System.out.println("Calling getColumnCount");
     return columnNames.length;
public int getRowCount() {
//System.out.println("Calling row count");
return data.length;
public String getColumnName(int col) {
return columnNames[col];
public Object getValueAt(int row, int col) {
return data[row][col];
* JTable uses this method to determine the default renderer/
* editor for each cell. If we didn't implement this method,
* then the last column would contain text ("true"/"false"),
* rather than a check box.
public Class getColumnClass(int c) {
return getValueAt(0, c).getClass();
* Don't need to implement this method unless your table's
* editable.
public boolean isCellEditable(int row, int col) {
//Note that the data/cell address is constant,
//no matter where the cell appears onscreen.
return true;
* Don't need to implement this method unless your table's
* data can change.
public void setValueAt(Object value, int row, int col) {
data[row][col] = value;
fireTableCellUpdated(row, col);

Shading part of a JTable Cell dependent upon the value of the cell

Hi
Was hoping some one woudl be able to provide some help with this. I'm trying to create a renderer that will "shade" part of a JTable cell's background depending upon the value in the cell as a percentage (E.g. if the cell contains 0.25 then a quarter of the cell background will be shaded)
What I've got so far is a renderer which will draw a rectangle whose width is the relevant percentage of the cell's width. (i.e. the width of the column) based on something similar I found in the forum but the part I'm struggling with is getting it to draw this rectangle in any cell other than the first cell. I've tried using .getCellRect(...) to get the x and y position of the cell to draw the rectangle but I still can't make it work.
The code for my renderer as it stands is:
import java.awt.Component;
import java.awt.Graphics;
import java.awt.Graphics2D;
import javax.swing.JLabel;
import javax.swing.JTable;
import javax.swing.table.TableCellRenderer;
public class PercentageRepresentationRenderer extends JLabel implements TableCellRenderer{
     double percentageValue;
     double rectWidth;
     double rectHeight;
     JTable table;
     int row;
     int column;
     int x;
     int y;
     public Component getTableCellRendererComponent(JTable table, Object value, boolean isSelected, boolean hasFocus, int row, int column) {
          if (value instanceof Number)
               this.table = table;
               this.row = row;
               this.column = column;
               Number numValue = (Number)value;
               percentageValue = numValue.doubleValue();
               rectHeight = table.getRowHeight(row);
               rectWidth = percentageValue * table.getColumnModel().getColumn(column).getWidth();
          return this;
     public void paintComponent(Graphics g) {
        x = table.getCellRect(row, column, false).x;
        y = table.getCellRect(row, column, false).y;
          setOpaque(false);
        Graphics2D g2d = (Graphics2D)g;
        g2d.fillRect(x,y, new Double(rectWidth).intValue(), new Double(rectHeight).intValue());
        super.paintComponent(g);
}and the following code produces a runnable example:
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.table.DefaultTableModel;
public class PercentageTestTable extends JFrame {
     public PercentageTestTable()
          Object[] columnNames = new Object[]{"A","B"};
          Object[][] tableData = new Object[][]{{0.25,0.5},{0.75,1.0}};
          DefaultTableModel testModel = new DefaultTableModel(tableData,columnNames);
          JTable test = new JTable(testModel);
          test.setDefaultRenderer(Object.class, new PercentageRepresentationRenderer());
          JScrollPane scroll = new JScrollPane();
          scroll.getViewport().add(test);
          add(scroll);
     public static void main(String[] args)
          PercentageTestTable testTable = new PercentageTestTable();
          testTable.pack();
          testTable.setVisible(true);
          testTable.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}If anyone could help or point me in the right direction, I'd appreciate it.
Ruanae

This is an example I published some while ago -
import java.awt.*;
import javax.swing.*;
import javax.swing.table.*;
public class Fred120 extends JPanel
    static final Object[][] tableData =
        {1, new Double(10.0)},
        {2, new Double(20.0)},
        {3, new Double(50.0)},
        {4, new Double(10.0)},
        {5, new Double(95.0)},
        {6, new Double(60.0)},
    static final Object[] headers =
        "One",
        "Two",
    public Fred120() throws Exception
        super(new BorderLayout());
        final DefaultTableModel model = new DefaultTableModel(tableData, headers);
        final JTable table = new JTable(model);
        table.getColumnModel().getColumn(1).setCellRenderer( new LocalCellRenderer(120.0));
        add(table);
        add(table.getTableHeader(), BorderLayout.NORTH);
    public class LocalCellRenderer extends DefaultTableCellRenderer
        private double v = 0.0;
        private double maxV;
        private final JPanel renderer = new JPanel(new GridLayout(1,0))
            public void paintComponent(Graphics g)
                super.paintComponent(g);
                g.setColor(Color.CYAN);
                int w = (int)(getWidth() * v / maxV + 0.5);
                int h = getHeight();
                g.fillRect(0, 0, w, h);
                g.drawRect(0, 0, w, h);
        private LocalCellRenderer(double maxV)
            this.maxV = maxV;
            renderer.add(this);
            renderer.setOpaque(true);
            renderer.setBackground(Color.YELLOW);
            renderer.setBorder(null);
            setOpaque(false);
            setHorizontalAlignment(JLabel.CENTER);
        public Component getTableCellRendererComponent(JTable table, Object value, boolean isSelected, boolean hasFocus, int row, int col)
            final JLabel label = (JLabel) super.getTableCellRendererComponent(table, value, isSelected, hasFocus, row, col);
            if (value instanceof Double)
                v = ((Double)value).doubleValue();
            return renderer;
    public static void main(String[] args) throws Exception
        final JFrame frame = new JFrame("Fred120");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setContentPane(new Fred120());
        frame.pack();
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
}

How to write an element in a JTable Cell

Probably it's a stupid question but I have this problem:
I have a the necessity to build a JTable in which, when I edit a cell and I push a keyboard button, a new Frame opens to edit the content of the cell.
But the problem is how to write something in the JTable cell, before setting its model. Because, I know, setCellAT() method of JTree inserts the value in the model and not in the table view. And repainting doesn't function!
What to do??
Thanks

Hi there
Depending on your table model you should normally change the "cell value" of the tablemodel.
This could look like:
JTable table = new JTable();
TableModel model = table.getModel();
int rowIndex = 0, columnIndex = 0;
model.setValueAt("This is a test", rowIndex, columnIndex);
The tablemodel should then fire an event to the view (i.e. JTable) and the table should be updated.
Hope this helps you

How to dynamically resize JPanel at runtime??

Hello Sir:
I met a problem, I need to resize a small JPanel called panel within a main Control JPanel (with null Layout) if I click the mouse then I can Drag and Resize this small JPanel Border to the size I need at runtime, I know I can use panel.setSize() or panel.setPreferredSize() methods at design time,
But I have no idea how to do it even I search this famous fourm,
How to dynamically resize JPanel at runtime??
Can any guru throw some light or good example??
Thanks

Why are you using a null layout? Wouldn't having a layout manager help you in this situation?

How to select rows in the inner JTable rendered in an outer JTable cell

I have wrriten the following code for creating cell specific renderer - JTable rendered in a cell of a JTable.
table=new JTable(data,columnNames)
public TableCellRenderer getCellRenderer(int row, int column)
if ((row == 0) && (column == 0))
return new ColorRenderer();
else if((row == 1) && (column == 0))
return new ColorRenderer1();
else
return super.getCellRenderer(row, column);
ColorRenderer and ColorRenderer1 are two inner classes, which implement TableCellRenderer to draw inner JTable on the outer JTable cell, having 2 rows and 1 column each.
Now what is happening the above code keeps executing continously, that is the classes are being initialised continously, inner JTables are rendered (drawn) continously, and this makes the application slow after some time. It throws java.lang.OutOfMemoryException.
WHY IS IT SO??? I can't understand where's the bug..
Any advice please???
Moreover i want selections in inner tables and not on outer table, how can this be possible.
I am working on this since a long time but have not yet found a way out...

With your help i have overcome the problem of continous repeatition.
The major problem which I am facing is, in selecting rows in the inner rendered JTables.
I have added listener on outer JTable which select rows on the outer JTable, hence the complete inner JTable which being treated as a row, gets selected.
The thing is i need to select the rows of inner rendered JTables,not the outer JTable.
How to go about it??
I have even added listener to inner rendered JTables, but only first row of every table gets selected.
Please help....
Thanks in advance.

How to display images in a Jtable cell-Urgent

Hay all,
Can anybody tell me that can we display images to JTable' cell,If yes the how do we do that(with some code snippet)? Its very urgent .Plz reply as soon as possible.

Here is an example
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.table.*;
class SimpleTableExample extends JFrame
     private     JPanel topPanel;
     private     JTable table;
     private     JScrollPane scrollPane;
     public SimpleTableExample()
          setTitle( "Table With Image" );
          setSize( 300, 200 );
          setBackground( Color.gray );
          topPanel = new JPanel();
          topPanel.setLayout( new BorderLayout() );
          getContentPane().add( topPanel );
          // Create columns names
          String columnNames[] = { "Col1", "Col2", "Col3" };
          // Create some data
          Object data[][] =
               { (ImageIcon) new ImageIcon("User.Gif"), (String) "100", (String)"101" },
               { (String)"102", (String)"103", (String)"104" },
               { (String)"105", (String)"106", (String)"107" },
               { (String)"108", (String)"109", (String)"110" },
          // Create a new table instance
DefaultTableModel model = new DefaultTableModel(data, columnNames);
          JTable table = new JTable( model )
               public Class getColumnClass(int column)
                    return getValueAt(0, column).getClass();
          };          // Add the table to a scrolling pane
          scrollPane = new JScrollPane( table );
          topPanel.add( scrollPane, BorderLayout.CENTER );
     public static void main( String args[] )
          SimpleTableExample mainFrame     = new SimpleTableExample();
          mainFrame.setVisible( true );
}

Image in a JTable cell

How can I put ImageIcon object in a JTable cell?

yes, I'mm trying :
ImageIcon icon = new ImageIcon("something.gif")
DefaultTableModel model = (DefaultTableModel)jTable1.getModel();
Object[] newRow = new Object[5];
newRow[1] = "I don't";
newRow[2] = "know, what";
newRow[3] = "I am doing"
newRow[4] = "wrong"
newRow[0] = icon;
model.addRow(newRow);
but icon doesn't show

Dynamically resize JTable cell to fit a JList

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