Java TableViewer：实现选中单元格时切换单元格图片的技术问询

Since you're using JFace's TableViewer with a ColumnLabelProvider to show CHECKED/UNCHECKED icons in the third column, the key here is to follow JFace's model-driven approach: update the underlying data model first, then refresh the viewer to reflect the change in the UI.

Here are two standard, maintainable approaches to achieve this:

Approach 1: Use EditingSupport (Recommended, JFace Standard) #

This integrates with the TableViewer's built-in editing framework, which supports accessibility, keyboard interactions, and aligns with JFace's best practices.

Step 1: Ensure your Person class has a setter for the married property #

First, make sure your Person model can update the married state (this is critical for model-driven UI updates):

public class Person {
    private boolean married;

    // Existing getter
    public boolean isMarried() {
        return married;
    }

    // Add this setter to modify the state
    public void setMarried(boolean married) {
        this.married = married;
    }

    // Other properties and methods...
}

Step 2: Implement the EditingSupport for the third column #

Replace your incomplete col.setEditingSupport(new ...) with this full implementation:

col.setEditingSupport(new EditingSupport(tableViewer) {
    @Override
    protected boolean canEdit(Object element) {
        // Allow editing for all rows in this column
        return true;
    }

    @Override
    protected CellEditor getCellEditor(Object element) {
        // Use CheckboxCellEditor to handle toggle logic - your custom icon will still be the visible UI element
        // If you don't want the default checkbox to show, use a NullCellEditor instead (see note below)
        return new CheckboxCellEditor(tableViewer.getTable());
    }

    @Override
    protected Object getValue(Object element) {
        // Sync the editor with the current model state
        return ((Person) element).isMarried();
    }

    @Override
    protected void setValue(Object element, Object value) {
        // Update the model with the new toggled state
        boolean newMarriedState = (boolean) value;
        ((Person) element).setMarried(newMarriedState);
        
        // Refresh only the affected row to update the icon efficiently
        tableViewer.update(element, null);
    }
});

Note: If you don't want the default checkbox from CheckboxCellEditor to be visible, replace it with a NullCellEditor (a minimal editor that triggers the edit flow without rendering anything). You'll still get the click-to-toggle behavior, and your custom icon will remain the only visible element.

Approach 2: Mouse Listener for Direct Click Handling #

If you prefer a more lightweight approach without using the editing framework, add a mouse listener to detect clicks on the third column:

tableViewer.getTable().addMouseListener(new MouseAdapter() {
    @Override
    public void mouseDown(MouseEvent e) {
        Table table = tableViewer.getTable();
        // Get the clicked table item and column
        TableItem clickedItem = table.getItem(new Point(e.x, e.y));
        if (clickedItem == null) return;

        TableColumn clickedColumn = table.getColumn(new Point(e.x, e.y));
        if (clickedColumn == null) return;

        // Verify we're clicking the third column (index 3)
        if (clickedColumn.getIndex() == 3) {
            Person person = (Person) clickedItem.getData();
            // Toggle the married state in the model
            person.setMarried(!person.isMarried());
            // Refresh the row to update the icon
            tableViewer.update(person, null);
        }
    }
});

Important Reminder #

Always modify the data model first rather than directly changing UI elements (like swapping images manually). This keeps your code consistent, avoids UI-model desyncs, and follows JFace's core design principles. Using tableViewer.update(element, null) is far more efficient than refreshing the entire viewer, as it only updates the affected row.

内容的提问来源于stack exchange，提问作者J.Doe