Repaint Table issue with Swing JTable - java

I am working with swing JTable and have a trouble with repainting table. I draw a JTable with thr following code
Object[] column = new Object[]{"Entity", "Attribute"};
Object[][] rowData = new Object[][]{{"E1", "A1"},{"E2", "A2"}};
TableCellRenderer cellRenderer = new TableCellRenderer();
JTable table = new JTable(new DefaultTableModel(rowData, column));
table.setCellSelectionEnabled(true);
table.getColumnModel().getColumn(0).setCellRenderer(cellRenderer);
Below is my table renderer code ..
public class TableCellRenderer implements javax.swing.table.TableCellRenderer {
//private JPanel panel;
JTextField field;
private JTable table;
#Override
public Component getTableCellRendererComponent(final JTable table, final Object value,
boolean isSelected, boolean hasFocus, final int row, final int column) {
this.table = table;
//JTextField field = null;
System.out.println("Rendere : Row : " + row + "Column : " + column);
final JPanel panel = new JPanel();
panel.setLayout(new BorderLayout());
JButton button = new JButton("?");
button.setPreferredSize(new Dimension(20, panel.getHeight()));
button.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent arg0) {
new SelectionDialog(panel, table, value, row, column);
}
});
if(table.getValueAt(row, column) != null){
field = new JTextField(table.getValueAt(row, column).toString());
}else{
field = new JTextField(table.getValueAt(row, column).toString());
}
field.setPreferredSize(new Dimension(30, panel.getHeight()));
panel.add(field, BorderLayout.WEST);
panel.add(button, BorderLayout.EAST);
return panel;
}
this is how i am updating contents of a cell in table..
SelectionDialog.this.table.getModel().setValueAt("E7", 0, 0);
I am updating the table model data via the SelectionDialog for e.g change data at row 0, colum 0 to E7 etc. After changing data in table model i have tried the following options but none of them has refreshed the table data in view however the data in model of JTable was updated correctly. If I add a new row on the fly and then call the below methods then every thing work fine but if I modify data in the model of an existing row then none of the solution mentioned below is working
//((DefaultTableModel)SelectionDialog.this.table.getModel()).addRow(new Object[]{"E3", "A3"});
//((DefaultTableModel)SelectionDialog.this.table.getModel()).fireTableCellUpdated(SelectionDialog.this.row, SelectionDialog.this.column);
//((DefaultTableModel)SelectionDialog.this.table.getModel()).fireTableChanged(new TableModelEvent(SelectionDialog.this.table.getModel()));
//((DefaultTableModel)SelectionDialog.this.table.getModel()).fireTableStructureChanged();
//SelectionDialog.this.table.repaint();
// SelectionDialog.this.table.revalidate();
Please provide any insights about the problem as I am to swing and may have missed some very prominent things.
Edit 1: Just adding one more note which i wanted to place earlier but don't know how i missed. Table is not updated in general but if i focus out from the cell in which change was made or i change the size of table then it immediately change the contents of that particular cell to fresh selected value.
Problem Solved:
I am placing my findings for someone who is facing similar problem.
I rendered a button and a text box inside each cell in my table. When button was clicked (Editor code is not provided as it looks irrelevant to me to place here) a dialog appear which inputs value from user and update the specific column and row.
The lines i mentioned as not working at the end of my post (before edit 1) were working correctly however renderer was not executing unless i manually focus out from the selected cell (whose button was clicked) or manually change the size of jtable which make sense as button was inside editor and button click shows that cell is edited and off-course renderer will not execute unless editing is finished which requires focus out or enter key etc.
I applied the following code as
table.editCellAt(-1, -1);
It focus out from the edited cell (edited with the button) and hence renderer executes and work as expected.

When you are using a DefaultTableModel and you want to update a certain value, you need to use the DefaultTableModel#setValueAt method.
Calling this method (on the Event Dispatch Thread of course) will update your model and fire the necessary events. Those events will cause your JTable to update itself.
A few additional remarks about your renderer:
Creating new components in each call of your renderer is not the way to go. This becomes incredibly slow for large tables. Create all components once in the constructor of your renderer, and just update their state
Adding a JButton to your table in the renderer has no effect, unless you have an editor as well. The button will not be clickable, and the action listener you attach to it will never be called. See the renderers and editors section in the JTable tutorial for more information.
There should be no need to call getValueAt in your renderer. The value is passed in as one of the arguments

Related

How to add a custom checkbox into JList (Java)?

This is how the program looks:
This is how I want it to look:
As you can see in the picture I have tried a bit and learned that I need to use ListCellRenderer, but the problem is i have created 2 custom png files
checked.png and
unchecked.png
when I click daily goals #1 it should give state = true and checked.png should appear and stay checked unless I click it again. Unchecked.png could be standard on the jList column.
I also want to place my checkbox 1 cm to the left of the end of the row (padding) not sure hows its done in java sadly. (You'll understand better by looking at the picture)
After looking through some guides I have learned that the only way to add extra stuff to a JList column is by using ListCellRenderer. I have tried quite a while with no success so thought of asking others. Does anyone have any ideas on how to do this?
The thought was to get it to work then display in a JTable by changing the Jtable column to Daily goals and displaying X to indicate the goal was achieved. But I think I should be able to do this, The main question is the custom checkbox implementation.
You can have two types of checkboxes to be used as jlist cell renderers, one for selected cells, another for unselected.
Use ImageIcon to decorate the checkbox with your images.
In your jlist cell render you need to have logic to return the intended checkbox to render that list cell.
Note to override the text in the checkbox to the actual list cell value
public class TestFrame extends JFrame {
ImageIcon iconChecked = new ImageIcon(TestFrame.class.getResource("checked.png"));
ImageIcon iconUnchecked = new ImageIcon(TestFrame.class.getResource("unchecked.png"));
JList jList = new JList(new Object[]{"ABC", "123"});
public TestFrame() {
this.add(jList);
jList.setSelectionMode(ListSelectionModel.MULTIPLE_INTERVAL_SELECTION);
jList.setCellRenderer(new ListCellRenderer() {
#Override
public Component getListCellRendererComponent(JList list, Object value, int index, boolean isSelected, boolean cellHasFocus) {
for (int i : list.getSelectedIndices()) {
if (index == i) {
JCheckBox checkBoxChecked = new JCheckBox(value.toString(), iconChecked);
return checkBoxChecked;
}
}
JCheckBox checkBoxUnchecked = new JCheckBox(value.toString(), iconUnchecked);
return checkBoxUnchecked;
}
});
}}

JTable JComboBox is defaulting to display 1st item when list is expanded

I have been trying to determine why my JComboBox is displaying the 1st item in the list through numerous Google searches, but I'm struggling to find relevant help. It could be that I don't know the correct terminology (hence the overly specific title of this question) and thus not finding the information that would explain my issue. I checked out the JComboBox API, and few of the listeners and models that it uses, but they did not seem likely candidates.
The JComboBox in question is inside a JTable, so I am not aware if that changes the default behaviour of it. The code I am using is as below:
//row and col are final due to usage inside anonymous inner class
public TableCellEditor getCellEditor(final int row, final int col)
{
String[] listItems = new String[arrayList.getSize()];
int i = -1;
for(String s : arrayList)
{
i++;
listItems[i] = s;
}
JComboBox<String> box = new JComboBox<>(listItems);
box.addItemListener(new ItemListener()
{
public void itemStateChanged(ItemEvent e)
{
if(e.getStateChange() == ItemEvent.SELECTED)
{
if(e.getItem().equals("Add/Edit Projectile"))
{
//Where Editor is a JFrame that will be opened
new Editor();
}
}
}
});
DefaultCellEditor list = new DefaultCellEditor(box);
}
Please note that the Arraylist in my program does not contain Strings, but instead a more complicated set of custom objects that I believe would distract from the main issue.
I haven't included a Renderer for JComboBox's in the JTable as I was happy enough with the way it appeared, and figured that my problem was more going to be something I have neglected to implement in the model/implemented wrong.
I've also provided a couple of screenshots to better portray my problem. The first image is when the JComboBox is not selected, and simply displaying the currently selected item.
The second image is when I have just clicked the JComboBox to bring up the list. As depicted, it will immediately bring up that first item, no matter what it is.
If anyone has any suggestions as to where to look/solutions, I would be very grateful.
EDIT
My particular table has two columns, where the left column is a variable name, and the right column is the value associated with the variable. The tables role is to display the properties of a selected object, where each value for different variable for different objects are likely to not be the same.
In this particular case, the cell displays a JComboBox with all the available Projectiles in the game we are making. Each enemy has a different type of projectile it defaults to. So when I click on a different enemy in our game area, the table will display all of their current properties (defaults if they have not been changed).
Enemies do have a getter for the Projectile, so I could determine what the currently selected enemy is, get it's projectile, do a toString() to find how it is to be represented in the list, and do a setValueAt().
The only problem is at the moment it is always selecting the first item in the list when the list is expanded.
Unless the values for the JComboBox are dynamically generated for each row, you should be able to just prepare the CellEditor ahead of time, for example...
JComboBox cb = new JComboBox(new String[]{"1", "2", "3", "4"});
DefaultCellEditor editor = new DefaultCellEditor(cb);
JTable table = new JTable(new DefaultTableModel(5, 1));
table.getColumnModel().getColumn(0).setCellEditor(editor);
This will set the selected value of the editor to the value of the cell when the editing process starts
Updated
In the case where the combobox values are dynamically generate per row, you could do something more like...
JComboBox cb = new JComboBox();
DefaultCellEditor editor = new DefaultCellEditor(cb) {
#Override
public Component getTableCellEditorComponent(JTable table, Object value, boolean isSelected, int row, int column) {
JComboBox editor = (JComboBox) getComponent();
String[] listItems = new String[arrayList.getSize()];
int i = -1;
for (String s : arrayList) {
i++;
listItems[i] = s;
}
DefaultComboBoxModel model = new DefaultComboBoxModel(listItems);
editor.setModel(model);
editor.setSelectedItem(value);
return editor;
}
};
JTable table = new JTable(new DefaultTableModel(5, 1));
table.getColumnModel().getColumn(0).setCellEditor(editor);
Note the use of editor.setSelectedItem(value);, this will set the selected value to the cells current value...
You could also re-use the model, clearing it each time and re-filling it with new values. You might find this more efficient if you have a large number of rows as you won't need to constantly create a new model each time a cell is edited
Thow this is an oldie...
Your problem is most likely you don't implement "equals" in the class used in the combo.
The Combo needs to select the current item when it is being prepared and does so by iterating through the elements of the model and selects the first one that is equal to the value in the cell. If none is encountered then it leaves the combo as is (either first element or the last used element in a previous cell edit)
This is how you should default to the previously selected element:
//...
Object selectedItem = box.getSelectedItem();
//Add some elements to the jComboBox
box.setSelectedItem(selectedItem);

getSelectedRow on a combobox cell editor

I need a listener on a CombobBox which is a cellEditor on a JTable.
This listener must give me the new selected value and the row id.
Problem with my below solution is that the listner is linked to all rows, so when I change one ComboBox value in one row, then move to another row (with a different combo value) an event is raised, but the selected row has not yet changed. How can I get rid of this case ?
Thanks
column = jTableCheck.getColumnModel().getColumn(9);
JComboBox comboBox = new JComboBox(comboGenre);
comboBox.addItemListener(new ItemListener(){
#Override
public void itemStateChanged(ItemEvent e) {
if (e.getStateChange() == ItemEvent.SELECTED) {
int row = jTableCheck.getSelectedRow();
Popup.info(e.getItem() + " SELECTED, row="+row);
}
}
});
column.setCellEditor(new DefaultCellEditor(comboBox));
Don't use an ItemListener on the combo box.
Instead you should be using a TableModelListener. An event will be fired whenever the data in the TableModel is changed. So you add the TableModelListener to the TableModel of your JTable.
The TableModelEvent will give your row/column of the cell that changed. You can get the changed value from the TableModel.
Or maybe you would want to use a Table Cell Listener which is similar to the TableModelListener except the code is only invoked when the value is actually changed and you use an Action to do the processing.
In fact, I already used a TableCellListener on another table, but forgot about that!
I found out a usefull class here: http://tips4java.wordpress.com/2009/06/07/table-cell-listener/

How to disable mouse activity when the value in a table is not in proper format?

I have a JTable with several columns. I override the getColumnClass method of the table model in order to specify which columns hold Integer values. So basically when a user tries to enter a String into an Integer column, he/she is not allowed to do so. The problem is that the user can still click on a button on my form which then uses the improper value in that cell.
How can I not allow the user to click on any buttons as long as one of the cells in the table is still being edited?
Add a PropertyChangeListener to the JTable:
#Override
public void propertyChange(PropertyChangeEvent e)
{
// A cell has started/stopped editing
if ("tableCellEditor".equals(e.getPropertyName()))
{
if (table.isEditing())
// disable buttons;
else
// enable buttons;
}
}
Or, if you don't want to disable the buttons, you can just add code to the ActionListener to check if the table.isEditing() and if so then just return.
You could use one of the 3 methods returning information on the editing process to enable your button.
JTable table = new JTable();
table.getEditingColumn();
table.getEditingRow();
table.getEditorComponent();
Check JTable documentation to see which could be best used for your case. You could make your button enabled only if
table.getEditorComponent();
returns null for example.
add a TableModelListener to your JTable
you should override its tableChanged method somewhat like this :
public void tableChanged(TableModelEvent e) {
int row = e.getFirstRow();
int column = e.getColumn();
TableModel model = (TableModel)e.getSource();
String columnName = model.getColumnName(column);
Object data = model.getValueAt(row, column);
//Check the data!!!
//Check the data!!!
//Check the data!!!
//disable the button if needed right here
}
ref:http://docs.oracle.com/javase/tutorial/uiswing/components/table.html#modelchange

How to add row of data to Jtable from values received from jtextfield and comboboxes

I have a JFrame Form which has JTextFields, JCombobox etc. and I am able to receive those values to variables and now I want to add the received data to JTable in new row when user clicks Add or something like that.
I have created JTable using net-beans the problem is what would be the code to add data from those variable to the rows of table. A basic example would be appreciated. I have tried numerous example and have added the code to ActionListener of the JButton but nothing Happens.
The Examples I tried are. How to add row in JTable? and How to add rows to JTable with AbstractTableModel method?
Any Help would be appreciated.
Peeskillet's lame tutorial for working with JTables in Netbeans GUI Builder
Set the table column headers
Highglight the table in the design view then go to properties pane on the very right. Should be a tab that says "Properties". Make sure to highlight the table and not the scroll pane surrounding it, or the next step wont work
Click on the ... button to the right of the property model. A dialog should appear.
Set rows to 0, set the number of columns you want, and their names.
Add a button to the frame somwhere,. This button will be clicked when the user is ready to submit a row
Right-click on the button and select Events -> Action -> actionPerformed
You should see code like the following auto-generated
private void jButton1ActionPerformed(java.awt.event.ActionEvent) {}
The jTable1 will have a DefaultTableModel. You can add rows to the model with your data
private void jButton1ActionPerformed(java.awt.event.ActionEvent) {
String data1 = something1.getSomething();
String data2 = something2.getSomething();
String data3 = something3.getSomething();
String data4 = something4.getSomething();
Object[] row = { data1, data2, data3, data4 };
DefaultTableModel model = (DefaultTableModel) jTable1.getModel();
model.addRow(row);
// clear the entries.
}
So for every set of data like from a couple text fields, a combo box, and a check box, you can gather that data each time the button is pressed and add it as a row to the model.
you can use this code as template please customize it as per your requirement.
DefaultTableModel model = new DefaultTableModel();
List<String> list = new ArrayList<String>();
list.add(textField.getText());
list.add(comboBox.getSelectedItem());
model.addRow(list.toArray());
table.setModel(model);
here DefaultTableModel is used to add rows in JTable,
you can get more info here.
String[] tblHead={"Item Name","Price","Qty","Discount"};
DefaultTableModel dtm=new DefaultTableModel(tblHead,0);
JTable tbl=new JTable(dtm);
String[] item={"A","B","C","D"};
dtm.addRow(item);
Here;this is the solution.

Categories

Resources