我想在可编辑JTable中的单元格中写入时更改字体大小

Question

for this, I tried this method

 table.setFont(new Font("Lucida Console", Font.PLAIN, 18));

but by using this I cannot find the appropriate Font at the time of Writing in the cell of the JTable .

I attach an image so you can find my question clearly .in this image u can see that at the time of writing font is small but after going to the next cell it becomes to change but I want that big font you can see that in image at the time of writing in the cell.

Answer 1

The problem is that table.setFont(new Font("Lucida Console", Font.PLAIN, 18)); will set the font of the cells when not being edited, it will not even set the font of the header. When editing, you have override the default setup by defining your own DefaultCellEditor . There are two ways to do so, the first (easier and cleaner) way is to create a JTextField and customize it the way you like and then pass it to the DefaultCellEditor constructor. The second (longer and not as clean) way is to override the getTableCellEditorComponent in the DefaultCellEditor and achieve the same result. I have included both solutions in a MCVE :

import java.awt.Color;
import java.awt.Font;
import javax.swing.DefaultCellEditor;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.JTextField;

public class Example extends JFrame {

    private final JTable table;
    private final String[] header = new String[]{"Column 0", "Column 1", "Column 2", "Column 3"};
    private String[][] data = new String[][]{
        {"(0,0)", "(1,0)", "(2,0)", "(3,0)"},
        {"(0,1)", "(1,1)", "(2,1)", "(3,1)"},
        {"(0,2)", "(1,2)", "(2,2)", "(3,2)"},
        {"(0,3)", "(1,3)", "(2,3)", "(3,3)"}};
    private final Font tableFont = new Font("Lucida Console", Font.PLAIN, 18);

    public Example() {
        table = new JTable(data, header);
        table.getTableHeader().setFont(tableFont);//font of the header
        table.setFont(tableFont);//set the font of the whole table

        //Since each cell is editable, you could think about it as a JTextField. You can create a
        //new JTextField and customize it. Then, you pass it as the new cell editor to the columns
        //of the JTable.
        JTextField textField = new JTextField();
        textField.setFont(tableFont);//this is what you need.
        //Extra changes, no boarder and selection colour is yellow... just to get the point across.
        textField.setBorder(null);
        textField.setSelectionColor(Color.YELLOW);

        //Create DefaultCellEditor and pass the textfield to the constructor.
        DefaultCellEditor customCellEditor = new DefaultCellEditor(textField);
        //Loop through all the columns and set the cell editor as the customized one.
        for (int i = 0; i < table.getColumnCount(); i++) {
            table.getColumnModel().getColumn(i).setCellEditor(customCellEditor);
        }
        /*
        OR, don't create a JTextField and use the following instead:
        DefaultCellEditor customCellEditor2 = new DefaultCellEditor(new JTextField()) {

            @Override
            public java.awt.Component getTableCellEditorComponent(JTable table, Object value,
                boolean isSelected, int row, int column) {
                JTextField result = (JTextField) super.getTableCellEditorComponent(table, value,
                    isSelected, row, column);
                result.setFont(tableFont);//this is what you need.
                result.setBorder(null);
                result.setSelectionColor(Color.YELLOW);
                return result;
            }
        };

        //Loop through all the columns and set the cell editor as the customized one.
        for (int i = 0; i < table.getColumnCount(); i++) {
            table.getColumnModel().getColumn(i).setCellEditor(customCellEditor2);
        }
         */

        //probably, you should make the height of the cells larger.
        for (int i = 0; i < table.getRowCount(); i++) {
            table.setRowHeight(i, 25);
        }

        add(new JScrollPane(table));
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setLocationRelativeTo(null);
        pack();
        setVisible(true);
    }

    public static void main(String[] args) {
        new Example();
    }

Answer 2

Maybe you could check how many characters have been typed in and calculate approximately how big the font should be. Calculation shouldn't be hard, is it? And then just change the size in this cell.