checkboxtableviewer.java

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     * @return <code>true</code> if the element is grayed,
     *   and <code>false</code> if not grayed
     */
    public boolean getGrayed(Object element) {
        Widget widget = findItem(element);
        if (widget instanceof TableItem) {
            return ((TableItem) widget).getGrayed();
        }
        return false;
    }

    /**
     * Returns a list of elements corresponding to grayed nodes in this
     * viewer.
     * <p>
     * This method is typically used when preserving the interesting
     * state of a viewer; <code>setGrayedElements</code> is used during the restore.
     * </p>
     *
     * @return the array of grayed elements
     * @see #setGrayedElements
     */
    public Object[] getGrayedElements() {
        TableItem[] children = getTable().getItems();
        List v = new ArrayList(children.length);
        for (int i = 0; i < children.length; i++) {
            TableItem item = children[i];
            if (item.getGrayed()) {
				v.add(item.getData());
			}
        }
        return v.toArray();
    }

    /* (non-Javadoc)
     * Method declared on StructuredViewer.
     */
    public void handleSelect(SelectionEvent event) {
        if (event.detail == SWT.CHECK) {
            super.handleSelect(event); // this will change the current selection

            TableItem item = (TableItem) event.item;
            Object data = item.getData();
            if (data != null) {
                fireCheckStateChanged(new CheckStateChangedEvent(this, data,
                        item.getChecked()));
            }
        } else {
			super.handleSelect(event);
		}
    }

    /* (non-Javadoc)
     * Method declared on Viewer.
     */
    protected void preservingSelection(Runnable updateCode) {

        TableItem[] children = getTable().getItems();
        CustomHashtable checked = newHashtable(children.length * 2 + 1);
        CustomHashtable grayed = newHashtable(children.length * 2 + 1);

        for (int i = 0; i < children.length; i++) {
            TableItem item = children[i];
            Object data = item.getData();
            if (data != null) {
                if (item.getChecked()) {
					checked.put(data, data);
				}
                if (item.getGrayed()) {
					grayed.put(data, data);
				}
            }
        }

        super.preservingSelection(updateCode);

        children = getTable().getItems();
        for (int i = 0; i < children.length; i++) {
            TableItem item = children[i];
            Object data = item.getData();
            if (data != null) {
                item.setChecked(checked.containsKey(data));
                item.setGrayed(grayed.containsKey(data));
            }
        }
    }

    /* (non-Javadoc)
     * Method declared on ICheckable.
     */
    public void removeCheckStateListener(ICheckStateListener listener) {
        checkStateListeners.remove(listener);
    }

    /**
     * Sets to the given value the checked state for all elements in this viewer.
     *
     * @param state <code>true</code> if the element should be checked,
     *  and <code>false</code> if it should be unchecked
     */
    public void setAllChecked(boolean state) {
        TableItem[] children = getTable().getItems();
        for (int i = 0; i < children.length; i++) {
            TableItem item = children[i];
            item.setChecked(state);
        }
    }

    /**
     * Sets to the given value the grayed state for all elements in this viewer.
     *
     * @param state <code>true</code> if the element should be grayed,
     *  and <code>false</code> if it should be ungrayed
     */
    public void setAllGrayed(boolean state) {
        TableItem[] children = getTable().getItems();
        for (int i = 0; i < children.length; i++) {
            TableItem item = children[i];
            item.setGrayed(state);
        }
    }

    /* (non-Javadoc)
     * Method declared on ICheckable.
     */
    public boolean setChecked(Object element, boolean state) {
        Assert.isNotNull(element);
        Widget widget = findItem(element);
        if (widget instanceof TableItem) {
            ((TableItem) widget).setChecked(state);
            return true;
        }
        return false;
    }

    /**
     * Sets which nodes are checked in this viewer.
     * The given list contains the elements that are to be checked;
     * all other nodes are to be unchecked.
     * <p>
     * This method is typically used when restoring the interesting
     * state of a viewer captured by an earlier call to <code>getCheckedElements</code>.
     * </p>
     *
     * @param elements the list of checked elements (element type: <code>Object</code>)
     * @see #getCheckedElements
     */
    public void setCheckedElements(Object[] elements) {
        assertElementsNotNull(elements);
        CustomHashtable set = newHashtable(elements.length * 2 + 1);
        for (int i = 0; i < elements.length; ++i) {
            set.put(elements[i], elements[i]);
        }
        TableItem[] items = getTable().getItems();
        for (int i = 0; i < items.length; ++i) {
            TableItem item = items[i];
            Object element = item.getData();
            if (element != null) {
                boolean check = set.containsKey(element);
                // only set if different, to avoid flicker
                if (item.getChecked() != check) {
                    item.setChecked(check);
                }
            }
        }
    }

    /**
     * Sets the grayed state for the given element in this viewer.
     *
     * @param element the element
     * @param state <code>true</code> if the item should be grayed,
     *  and <code>false</code> if it should be ungrayed
     * @return <code>true</code> if the element is visible and the gray
     *  state could be set, and <code>false</code> otherwise
     */
    public boolean setGrayed(Object element, boolean state) {
        Assert.isNotNull(element);
        Widget widget = findItem(element);
        if (widget instanceof TableItem) {
            ((TableItem) widget).setGrayed(state);
            return true;
        }
        return false;
    }

    /**
     * Sets which nodes are grayed in this viewer.
     * The given list contains the elements that are to be grayed;
     * all other nodes are to be ungrayed.
     * <p>
     * This method is typically used when restoring the interesting
     * state of a viewer captured by an earlier call to <code>getGrayedElements</code>.
     * </p>
     *
     * @param elements the array of grayed elements
     *
     * @see #getGrayedElements
     */
    public void setGrayedElements(Object[] elements) {
        assertElementsNotNull(elements);
        CustomHashtable set = newHashtable(elements.length * 2 + 1);
        for (int i = 0; i < elements.length; ++i) {
            set.put(elements[i], elements[i]);
        }
        TableItem[] items = getTable().getItems();
        for (int i = 0; i < items.length; ++i) {
            TableItem item = items[i];
            Object element = item.getData();
            if (element != null) {
                boolean gray = set.containsKey(element);
                // only set if different, to avoid flicker
                if (item.getGrayed() != gray) {
                    item.setGrayed(gray);
                }
            }
        }
    }
}