Develop Reference

Access JTable cell component

Ok I have a JTable where I'm displaying a JList on every cell. To do this I had to implement TableCellRenderer and extend DefaultCellEditor. Here is where I return the actual JList to be rendered in GUI.
What I want to do is when user de-selects an item from a JList, I want to also de-select all items for all JLists for that table row starting at the clicked column.
My problem is that I can't figure out a way to de-select all items that come after the current clicked table column. All I can access is this DefaultListModel. I guess I need to access the actual JList in order to remove all selected items.
Below is method I'm using. Any ideas how to do this? Thanks.
public void deselectFromLocation(int row_, int column_){
DefaultTableModel dtm = (DefaultTableModel) table1.getModel();
int cols = dtm.getColumnCount();
for(int i=column_; i<cols;i++){
PCSListModel lm = (PCSListModel) dtm.getValueAt(row_, i);
//How can I access the actual JList object in order to remove all selected items?
//The PCSListMode is DefaultListModel and has no access to JList object. Thanks.
}
}

Presumably, your renderer and editor obtain the existing selection state from your TableModel, perhaps updating an instance of ListSelectionModel that is used as part of preparing the component for use. You can update the other model value(s) in your implementation of stopCellEditing(). Your TableModel will have to fire a suitable TableModelEvent for the other cells; do not do so for the value being edited. A related example is seen here.

Selected Row in JTable along with Sorting

I have a very odd issue with JTable.
I put data in JTable from DB. When user double clicks on any cell, it copies the cell contents of the first column of the row where user double clicked. So far, it works perfect.
The problem arises when the user sorts the JTable by clicking on the header. when the table has been sorted and now when the user double clicks on any row, it doesn't what is currently stored on that row's first column. It copies what was originally stored on the first column of that row when the JTable was not sorted.
Any ideas?

Problem:
The problem here is that you are getting the initial rows indexes in the JTable TableModel, and not the relevants row indexes shown in the table view.
Solution:
You can map the shown indexes of a sorted jTable with their relevants ones in the dataModel using convertRowIndexToModel(index) method which takes in input the row index in the view and returns the index of the corresponding row in the model.
Let's say that you have the following jTable:
TableModel myModel = createMyTableModel();
JTable table = new JTable(myModel);
table.setRowSorter(new TableRowSorter(myModel));
And then loop throught model indexes and use this method with each index to get its corresponding one in the TableModel:
table.getRowSorter().convertRowIndexToModel(0); // index 0 here

As suggested in How to Use Tables: Sorting and Filtering, "When using a sorter, always remember to translate cell coordinates." Most likely, you have neglected this in your event handler.

Try Sorting your JTable TableModel data too. Jtable -> TableModel is the one which hold the actual data. JTable is just a view.

Javax Swing JTable::getModel vs JTable::getColumnModel

Hello I have been working with javax swing and I came across a weird problem and got me questioning.
I can for example:
JTable table = new JTable();
// Indeed, 2 different objects:
// The TableModel (which, i think is supposed to contain rows and columns?
DefaultTableModel dtm = (DefaultTableModel) table.getModel();
// And the column model, supposed to define the columns of a table?
TableColumnModel tcm = table.getColumnModel();
// I can add columns to my table in two different manners
dtm.addColumn("A Column");
// or
TableColumn column = new TableColumn();
column.setHeaderValue("Another column");
column.setWidth(120);
column.setMinWidth(120);
column.setMaxWidth(120);
tcm.addColumn(column);
// And notice that both commands will add a column in the table
// So our table model should now have 2 columns.
// But does it?
System.out.println(dtm.getColumnCount()); // outputs 1;
System.out.println(tcm.getColumnCount()); // outputs 2;
System.out.println(table.getColumnCount()); // outputs 2;
// The visual shows 2 columns, but the model has only 1.
From that I can tell JTable uses tableColumnModel and tableColumnModel gets all the columns added into tableModel, but, when I add a column to the TableModel it gets added to the table, but the tableModel remains outdated.
Now, the problem is: it's really interesting to add a column via columnModel because I can define the sizes, layout, editable options there, but in this way I cannot add any data to it from the tableModel, since that column doesn't appear on the tableModel.
Any thoughts on this?

The TableModel is used to contain data. The data is accessible in row/columns.
The TableColumnModel is used by JTable to control the View of the data. That is it controls the columns that are displayed in the JTable. You can also reorder the columns to display the data in a different order.
...but in this way I cannot add any data to it from the tableModel, since that column doesn't appear on the tableModel
That is correct. The purpose of the TableColumnModel is to simply customize the view, not manipulate data.
Maybe you have an application that contains many columns of data, but access to specific columns is limited by "security level". In this case the data is always stored in the TableModel, but you need to change the view to control which columns of data are visible. So you can remove/add columns from the TableColumnModel.
When you add a column to the TableModel, the JTable gets notified and it recreates all the TableColumns for you. This can be a good or bad thing because when the TableColumnModel is recreated you lose any custom renderers and editor that you may have added to a TableColumn. You can prevent this from happening buy using:
table.setAutoCreateColumnsFromModel( false );
Now the TableColumnModel will not be updated and it is your responsibility to manually create and add the TableColumn to the TableColumnModel.
But in general you:
add/change data through the TableModel.
change the view through the TableColumnModel.

How to add others Comboboxes in the same column [duplicate]

I have a written an AbstractTableModel for my JTable in my application. I see from tutorials that I can make the column to have a combobox by getting the column model and then the specific column for example:
TableColumn sportColumn = table.getColumnModel().getColumn(2);
...
JComboBox comboBox = new JComboBox();
comboBox.addItem("Snowboarding");
comboBox.addItem("Rowing");
comboBox.addItem("Chasing toddlers");
comboBox.addItem("Speed reading");
comboBox.addItem("Teaching high school");
comboBox.addItem("None");
sportColumn.setCellEditor(new DefaultCellEditor(comboBox));
But how do I do this for a specific cell or a row?

The JTable’s default implementation is column-based. The only way to change that behavior, if you want to have row or single-cell based choices, is to create a subclass of JTable and override the method public TableCellEditor getCellEditor(int row, int column). Inside your implementation you can use the provided row and column indices to make a different choice. The JTable will always use this method to get the cell editor.

you would need to use, override
prepareEditor
TableCellEditor(required to synchronize editor and renderer)

The best way to set rows and headers separately after JTable creation?

It means I need setData and setHeaders functions for JTable

Like Gilbert says, there is no method of the AbstractTableModel that will allow you to set the values of the headers after the JTable is up, since it is not a very common requirement. Still there is a simple work-around to that. I can not say if it is the best way to do it, but it will get you there...
columnNumber is the number of the column you want to change and newHeaderString is the new String you want to use.
jTable1.getColumnModel().getColumn(columnNumber).setHeaderValue(newHeaderString);
jScrollPane1.setViewportView(jTable1);
Since there is a getTableHeader() method, you could call it if you need to further modify your table header properties.
As for setting new data in any row, use jTable1.setValueAt(newObject, row, col);

if you use a TableModel, you can change the data contents, but not the column headers.
TableModel model = new DefaultTableModel(rowData, columnNames);
JTable table = new JTable(model)
rowData and columnNames have to be defined before you create the table.
The TableModel interface has a setValueAt method. The TableModel interface has no method for setting column names.