使用 TableCellEditor 时如何获取鼠标单击位置的组件?

2024-02-12

我用的是自定义的TableCellRenderer与多个JFormattedTextField在表格单元格中。我使用相同的组件TableCellEditor。现在我需要知道在什么方面JFormattedTextField用户单击,以及该字段中的位置(可以使用viewToModel).

使用自定义时TableCellEditor,唯一获得的方法是Point鼠标点击是isCellEditable(EventObject e) http://docs.oracle.com/javase/7/docs/api/javax/swing/CellEditor.html#isCellEditable%28java.util.EventObject%29中的方法CellEditor. The Point给出的是在父母坐标系中。

anEvent 位于调用组件坐标系中。

但是如何获取点击坐标处的组件呢?我尝试过findComponentAt(Point p) http://docs.oracle.com/javase/7/docs/api/java/awt/Container.html#findComponentAt%28java.awt.Point%29但它返回null for me.

这是我测试过的一些代码:

@Override
    public boolean isCellEditable(EventObject e) {

        if(e instanceof MouseEvent) {
            MouseEvent ev = (MouseEvent)e;
            Point p = ev.getPoint();

            // gives strange values
            Point p3 = editor.getLocation();

            // x: 0 y: 0
            Point tp = ((JTable)e.getSource()).getLocation();

            // these returns null
            Component c1 = renderer.findComponentAt(p);
            Component c2 = editor.findComponentAt(p);

            System.out.println("Click at " + p + " editor at: " + p3);
        }

        return true;
    }

组件位置的值editor.getLocation();给出 y 坐标的几乎随机值(例如,当在表中使用 5 行时)。

如何获取用户在使用时单击的组件TableCellEditor and a TableCellRenderer?


这是一个完整的示例:

public class FormattedTableEditDemo extends JFrame {

    public FormattedTableEditDemo() {

        MyTableModel model = new MyTableModel();
        MyTableCellEditorAndRenderer cellEditorAndRenderer =
                new MyTableCellEditorAndRenderer();     

        JTable table = new JTable(model);
        table.setDefaultRenderer(BigDecimal.class, cellEditorAndRenderer);
        table.setDefaultEditor(BigDecimal.class, cellEditorAndRenderer);
        table.setRowHeight(40);

        add(new JScrollPane(table));
        pack();
        setDefaultCloseOperation(EXIT_ON_CLOSE);
        setVisible(true);

    }

    class MyTableCellEditorAndRenderer extends AbstractCellEditor
            implements TableCellEditor, TableCellRenderer {

        MyCellPanel editor = new MyCellPanel();
        MyCellPanel renderer = new MyCellPanel();

        @Override
        public Object getCellEditorValue() {
            return editor.getValue();
        }

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

        @Override
        public Component getTableCellEditorComponent(JTable table,
                Object value, boolean isSelected, int row, int column) {
            editor.setValue(value);
            return editor;
        }

        @Override
        public boolean shouldSelectCell(EventObject e) {
            return false;
        }

        @Override
        public boolean isCellEditable(EventObject e) {

            if(e instanceof MouseEvent) {
                MouseEvent ev = (MouseEvent)e;
                Point p = ev.getPoint();

                // gives strange values
                Point p3 = editor.getLocation();

                // x: 0 y: 0
                Point tp = ((JTable)e.getSource()).getLocation();

                // these returns null
                Component c1 = renderer.findComponentAt(p);
                Component c2 = editor.findComponentAt(p);

                System.out.println("Click at " + p + " editor at: " + p3);
            }

            return true;
        }

    }

    class MyCellPanel extends JPanel {

        JFormattedTextField field1 = new JFormattedTextField();
        JFormattedTextField field2 = new JFormattedTextField();

        public MyCellPanel() {

            field1.setColumns(8);
            field2.setColumns(8);

            field2.setValue(new BigDecimal("0.00"));

            setLayout(new BorderLayout());
            add(field1, BorderLayout.WEST);
            add(Box.createHorizontalStrut(30));
            add(field2, BorderLayout.EAST);
        }

        public Object getValue() {
            return field1.getValue();
        }

        public void setValue(Object value) {
            field1.setValue(value);
        }
    }

    class MyTableModel extends AbstractTableModel {

        List<BigDecimal> values = new ArrayList<BigDecimal>();

        public MyTableModel() {

            // test values
            values.add(new BigDecimal("37.00"));
            values.add(new BigDecimal("4305.90"));
            values.add(new BigDecimal("386.04"));
            values.add(new BigDecimal("3486.58"));
            values.add(new BigDecimal("6546.45"));
        }

        @Override
        public int getColumnCount() {
            return 1;
        }

        @Override
        public int getRowCount() {
            return values.size();
        }

        @Override
        public Object getValueAt(int row, int column) {
            return values.get(row);
        }

        @Override
        public boolean isCellEditable(int row, int column) {
            return true;
        }

        @Override
        public Class<?> getColumnClass(int column) {
            return BigDecimal.class;
        }

    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {

            @Override
            public void run() {
                new FormattedTableEditDemo();
            }

        });
    }

}

不完全确定我明白出了什么问题(如果我不在,请告诉我,这样我就可以删除这个:-)

假设您想获得触发编辑开始的鼠标(单击/按下)下的“真实”组件,技巧是进行转换(从父坐标到编辑器坐标)after编辑器被添加到其父级。这对于 shouldSelectCell 是有保证的,但对于 isCellEditable 则不然(后者被称为before)

A 最近的回答 https://stackoverflow.com/questions/8119718/treecelleditor-must-select-cell-to-edit-even-if-shouldselectcell-return-false/8279716#8279716在树的上下文中(应该足够相似)有一些可运行的示例。这是相关的片段:

/**
 * At this point in time the editing component is added to the table (not documented!) but
 * table's internal cleanup might not yet be ready
 */ 
@Override
public boolean shouldSelectCell(EventObject anEvent) {
    if (anEvent instanceof MouseEvent) {
        redirect((MouseEvent) anEvent);
    }
    return false;
}

private void redirect(final MouseEvent anEvent) {
    SwingUtilities.invokeLater(new Runnable() {
        @Override
        public void run() {
            MouseEvent ev = SwingUtilities.convertMouseEvent(anEvent.getComponent(), anEvent, editor);
            // at this point you have the mouse coordinates in the editor's system
            // do stuff, like f.i. findComponent
            ....
        }
    });
}
本文内容由网友自发贡献,版权归原作者所有,本站不承担相应法律责任。如您发现有涉嫌抄袭侵权的内容,请联系:hwhale#tublm.com(使用前将#替换为@)

使用 TableCellEditor 时如何获取鼠标单击位置的组件? 的相关文章

随机推荐