TableLayout

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TableLayout.jpg

Gleich vorab der Hinweis: Es geht in diesem Artikel nicht um den LayoutManager TableLayout.

Die unten gezeigte Klasse "TableLayout" ermöglicht das Anordnen von Swing Komponenten in Form einer Tabelle. "TableLayoutDemo" zeigt ein Beispiel, wie sie verwendet werden kann:

import java.awt.*;
import java.util.*;
import javax.swing.*;

/**
 * TableLayoutDemo shows you, how to use the "TableLayout" class.
 * 
 * @author André Uhres
 */
public class TableLayoutDemo extends JFrame {

    private TableLayout tableLayout;
    private final Random r;

    /**
     * Create a TableLayoutDemo.
     */
    public TableLayoutDemo() {
        super("TableLayout Demo");
        r = new Random();
        setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        setSize(600, 600);
        setLocationRelativeTo(null);
        //create empty TableLayout:
        tableLayout = new TableLayout();
        //fill the TableLayout:
        for (int row = 0; row < 5; row++) {
            //create a test panel:
            JPanel panel = createTestPanel(row);
            //add to TableLayout:
            tableLayout.addRow(panel);
        }
        getContentPane().add(new JScrollPane(tableLayout), BorderLayout.CENTER);
    }

    private JPanel createTestPanel(int row) {
        JPanel panel = new JPanel();
        panel.add(new JLabel("Panel " + row));
        //generate random height for testing only:
        int height = r.nextInt(200);
        if (height < 34) {
            height = 34;
        }
        panel.setPreferredSize(new Dimension(0, height));
        return panel;
    }

    /**
     * Method for testing.
     * @param args
     */
    public static void main(final String[] args) {
        EventQueue.invokeLater(new Runnable() {

            @Override
            public void run() {
                new TableLayoutDemo().setVisible(true);
            }
        });

    }
}
import java.awt.*;
import java.awt.event.*;
import java.io.*;
import java.util.*;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.table.*;

/**
 * With "TableLayout" we can lay out any Swing components in the form of a table.
 * 
 * @author André Uhres
 */
public class TableLayout extends JTable {

    /**
     * Constructs a TableLayout with 0 rows and 0 columns.
     * For adding data see the methods "addColumns" and "addRow".
     * Note that the method "addRow" automatically adds missing columns.
     */
    public TableLayout() {
        super(0, 0);
        setDefaultRenderer(JComponent.class, new TableLayoutRenderer());
        setDefaultEditor(JComponent.class, new TableLayoutEditor());
        setSurrendersFocusOnKeystroke(true);
    }

    @Override
    public TableCellRenderer getCellRenderer(final int row, final int column) {
        TableColumn tableColumn = getColumnModel().getColumn(column);
        TableCellRenderer renderer = tableColumn.getCellRenderer();
        if (renderer == null) {
            Class c = getColumnClass(column);
            if (c.equals(Object.class)) {
                Object o = getValueAt(row, column);
                if (o != null) {
                    c = getValueAt(row, column).getClass();
                }
            }
            renderer = getDefaultRenderer(c);
        }
        return renderer;
    }

    @Override
    public TableCellEditor getCellEditor(final int row, final int column) {
        TableColumn tableColumn = getColumnModel().getColumn(column);
        TableCellEditor editor = tableColumn.getCellEditor();
        if (editor == null) {
            Class c = getColumnClass(column);
            if (c.equals(Object.class)) {
                Object o = getValueAt(row, column);
                if (o != null) {
                    c = getValueAt(row, column).getClass();
                }
            }
            editor = getDefaultEditor(c);
        }
        return editor;
    }

    /**
     *
     * @param columnNames one or more names to be added as columns
     */
    public void addColumns(final String... columnNames) {
        DefaultTableModel model = (DefaultTableModel) getModel();
        for (String name : columnNames) {
            model.addColumn(name);
        }
    }

    /**
     *
     * @param objects one or more components to be added as a row
     */
    public void addRow(final Object... objects) {
        DefaultTableModel model = (DefaultTableModel) getModel();
        while (model.getColumnCount() < objects.length) {
            model.addColumn("");
        }
        model.addRow(objects);
        int h = getRowHeight(getRowCount() - 1);
        for (Object obj : objects) {
            JComponent comp = null;
            if (obj instanceof JComponent) {
                comp = (JComponent) obj;
                int h2 = comp.getPreferredSize().height;
                if (h < h2) {
                    h = h2;
                }
            }
        }
        setRowHeight(getRowCount() - 1, h);
    }

    /**
     * 
     * @param row the model index of the row
     */
    public void removeRow(int row) {
        if (row > -1) {
            DefaultTableModel model = (DefaultTableModel) getModel();
            TableCellEditor editor = getCellEditor();
            if (editor != null) {
                editor.stopCellEditing();
            }
            model.removeRow(convertRowIndexToModel(row));
        }

    }

    private class TableLayoutEditor implements TableCellEditor, Serializable {

        protected EventListenerList listenerList = new EventListenerList();
        protected transient ChangeEvent changeEvent = null;
        protected JComponent editorComponent = null;

        public Component getComponent() {
            return editorComponent;
        }
        /* implement CellEditor:
        getCellEditorValue
        isCellEditable
        shouldSelectCell
        stopCellEditing
        cancelCellEditing
        addCellEditorListener
        removeCellEditorListener
         */

        @Override
        public Object getCellEditorValue() {
            return editorComponent;
        }

        @Override
        public boolean isCellEditable(final EventObject anEvent) {
            return true;
        }

        @Override
        public boolean shouldSelectCell(final EventObject anEvent) {
            if (editorComponent != null && anEvent instanceof MouseEvent
                    && ((MouseEvent) anEvent).getID() == MouseEvent.MOUSE_PRESSED) {
                Component dispatchComponent =
                        SwingUtilities.getDeepestComponentAt(editorComponent, 3, 3);
                MouseEvent e = (MouseEvent) anEvent;
                MouseEvent e2 = new MouseEvent(dispatchComponent,
                        MouseEvent.MOUSE_RELEASED, e.getWhen() + 100000,
                        e.getModifiers(), 3, 3, e.getClickCount(), e.isPopupTrigger());
                dispatchComponent.dispatchEvent(e2);
                e2 = new MouseEvent(dispatchComponent, MouseEvent.MOUSE_CLICKED,
                        e.getWhen() + 100001, e.getModifiers(), 3, 3, 1, e.isPopupTrigger());
                dispatchComponent.dispatchEvent(e2);
            }
            return true;
        }

        @Override
        public boolean stopCellEditing() {
            fireEditingStopped();
            return true;
        }

        @Override
        public void cancelCellEditing() {
            fireEditingCanceled();
        }

        @Override
        public void addCellEditorListener(final CellEditorListener l) {
            listenerList.add(CellEditorListener.class, l);
        }

        @Override
        public void removeCellEditorListener(final CellEditorListener l) {
            listenerList.remove(CellEditorListener.class, l);
        }

        protected void fireEditingStopped() {//used in stopCellEditing
            Object[] listeners = listenerList.getListenerList();
            // Process the listeners last to first, notifying
            // those that are interested in this event
            for (int i = listeners.length - 2; i >= 0; i -= 2) {
                if (listeners[i] == CellEditorListener.class) {
                    // Lazily create the event:
                    if (changeEvent == null) {
                        changeEvent = new ChangeEvent(this);
                    }
                    ((CellEditorListener) listeners[i + 1]).editingStopped(changeEvent);
                }
            }
        }

        protected void fireEditingCanceled() {//used in cancelCellEditing
            // Guaranteed to return a non-null array
            Object[] listeners = listenerList.getListenerList();
            // Process the listeners last to first, notifying
            // those that are interested in this event
            for (int i = listeners.length - 2; i >= 0; i -= 2) {
                if (listeners[i] == CellEditorListener.class) {
                    // Lazily create the event:
                    if (changeEvent == null) {
                        changeEvent = new ChangeEvent(this);
                    }
                    ((CellEditorListener) listeners[i + 1]).editingCanceled(changeEvent);
                }
            }
        }

// implement TableCellEditor:
        @Override
        public Component getTableCellEditorComponent(final JTable table,
                final Object value, final boolean isSelected,
                final int row, final int column) {
            editorComponent = (JComponent) value;
            return editorComponent;
        }
    }

    private class TableLayoutRenderer implements TableCellRenderer {

        @Override
        public Component getTableCellRendererComponent(final JTable table,
                final Object value, final boolean isSelected,
                final boolean hasFocus, final int row, final int column) {
            return (JComponent) value;
        }
    }
}