JTable中的条件JComboBox - 如何自动更改值

Question

I have a table filled with comboboxes, What I want to do is the folowing: If an element in a combobox is selected, then automatically change the selection on another combo (the reciprocal). I can't figureout a way to do it. Here I post an image describing what I want to do.

The code of my table is the following:

public void createCriteriaMatrix(){

    jTableCriteria = new JTable();

    // COLUMNS
    String[] column = new String[problem.getCriteria()+1];        
    for(int i=0; i<problem.getCriteria()+1; i++){
          column [i] = " "+i;
          if(i==0){
              column [i] = " ";
          }
     }
    // DATA CELLS
   String [][] data = new String[problem.getCriteria()][problem.getCriteria()+1];
    for(int j=0; j<problem.getCriteria()+1; j++){
        for(int i=0; i<problem.getCriteria(); i++){
            data [i][j]=" ";
            if(j==0){
                data [i][j] = " "+(i+1);
            }
        }
    }
    //SOME TABLE FORMAT
    DefaultTableModel model = new DefaultTableModel(data , column ){
        @Override
        public boolean isCellEditable(int row, int column) {
            return column != 0;
        }                
    };

    //Calling to RenderCells() to format cell colors
    jTableCriteria.setDefaultRenderer (Object.class, new RenderCells());    
    jTableCriteria.setModel(model);
    jTableCriteria.getTableHeader().setReorderingAllowed(false);

    this.placeCombosTable();
}

public void placeCombosTable(){
    for(int i=0; i<=problem.getCriteria(); i++){
        for(int j=0; j<=problem.getCriteria(); j++){
            TableColumn weighting= jTableCriteria.getColumnModel().getColumn(i);
            JComboBox comboBox = new JComboBox();
            comboBox.addItem("1");
            comboBox.addItem("2");
            comboBox.addItem("3");
            comboBox.addItem("4");
            comboBox.addItem("5");
            comboBox.addItem("6");
            comboBox.addItem("7");
            comboBox.addItem("1/2");
            comboBox.addItem("1/3");
            comboBox.addItem("1/4");
            comboBox.addItem("1/5");
            comboBox.addItem("1/6");
            comboBox.addItem("1/7");
            if(i==j){
               comboBox.setSelectedIndex(0);
            }
            weighting.setCellEditor(new DefaultCellEditor(comboBox));
        }

    }             
}

Answer 1

• use code example from official Oracle tutorial How to use Table - Using a Combo Box as an Editor , in model is stoere only selected value from JComboBox, not JComboBox

• you have to override setValueAt , 1st part inside setValueAt is about to store integer value from current JComboBox as CellEditor to XxxTableModel , second part is about to set value to (another JTables cell) another cell in XxxTableModel

---

• I'd be

  1. to use DefaultTableModel

  2. there is to override getColumnClass for JComboBox (to have to contains integer to avoiding parsing)

  3. isCellEditable

  4. setValueAt in SSCCE form

Answer 2

You can make ActionListener that listen to ComboBox state changed and change other ComboBox value. Also you can try PopupMenuEvent for this.

Answer 3

I solved it with an Array for the reciprocal pairwise comparison (to compare and then set the other combo with the correct value), a Listener for the combobox and a setValueAt() instead of a setSelectedItem(). The code is the following:

 public void placeCombosTable(){
    for(int i=0; i<=problem.getCriteria(); i++){
        for(int j=0; j<=problem.getCriteria(); j++){
            TableColumn weighting = jTableCriteria.getColumnModel().getColumn(i);
            JComboBox comboBox = new JComboBox();
            comboBox.addItem("1");
            comboBox.addItem("2");
            comboBox.addItem("3");
            comboBox.addItem("4");
            comboBox.addItem("5");
            comboBox.addItem("6");
            comboBox.addItem("7");
            comboBox.addItem("1/2");
            comboBox.addItem("1/3");
            comboBox.addItem("1/4");
            comboBox.addItem("1/5");
            comboBox.addItem("1/6");
            comboBox.addItem("1/7");
            if(i==j){
               comboBox.setSelectedIndex(0);
            }
            //SCALE
            final String scale[][] = {
                { "1", "2",   "3",  "4",  "5",  "6",  "7" },
                { "1", "1/2", "1/3","1/4","1/5","1/6","1/7" }
            };
            //LISTENER
            comboBox.addActionListener(
                    new ActionListener(){
                        @Override
                        public void actionPerformed(ActionEvent e){
                            JComboBox combo = (JComboBox)e.getSource();
                            //LOOK FOR THE RECIPROCAL ON THE SCALE
                            String item = (String)combo.getSelectedItem();
                            String itemReciprocal = "";
                            for (int i = 0; i <= 0; i++) {
                                for (int j = 0; j < 7; j++) {
                                    if(item.equalsIgnoreCase(scale[i][j])){
                                        itemReciprocal = scale[1][j];
                                    }                                                                         
                                }
                            }
                            //WITH THE RECIPROCAL I PROCEEDE TO SET THE CORRESPONDING CELL
                            int row = jTableCriteria.getSelectedRow()+1;
                            int column = jTableCriteria.getSelectedColumn();
                            int reciprocalRow = column ;
                            int reciprocalColumn = row ;
                            jTableCriteria.getModel().setValueAt(itemReciprocal, reciprocalRow , reciprocalColumn );

                        }
                    }            
            );
            weighting.setCellEditor(new DefaultCellEditor(comboBox));
        }

    }             
}