/* Glazed Lists (c) 2003-2006 */
/* http://publicobject.com/glazedlists/ publicobject.com,*/
/* O'Dell Engineering Ltd.*/
package ca.odell.glazedlists.swing;
import ca.odell.glazedlists.TreeList;
import javax.swing.*;
import javax.swing.table.DefaultTableCellRenderer;
import javax.swing.table.TableCellRenderer;
import java.awt.*;
/**
* This renderer removes some of the burden of producing an appropriate looking
* component for the hierarchy column of a tree table. Specifically, it takes
* care of adding components to a panel that render a node location within the
* tree, but leaves the rendering of the <strong>data</strong> of the node to
* a delegate {@link TableCellRenderer} that is supplied in the constructor.
*
* <p>For example, in the following tree representation, the spacing and +/-
* icons would be added to each tree node by this renderer, while the data text
* would be added by the component returned from the delegate
* {@link TableCellRenderer}.
*
* <pre>
* - Cars
* + BMW
* - Ford
* Taurus
* Focus
* - Lexus
* ES 300
* LS 600h L
* </pre>
*
* @author James Lemieux
*/
public class TreeTableCellRenderer implements TableCellRenderer {
/** The panel capable of laying out a indenter component, expander button, spacer component, and data Component to produce the entire tree node display. */
private final TreeTableCellPanel component = new TreeTableCellPanel();
/** The user-supplied renderer that produces the look of the tree node's data. */
private TableCellRenderer delegate;
/** The data structure that answers questions about the tree node. */
private TreeList treeList;
/** <tt>true</tt> indicates the expander button should be visible even if the parent has no children. */
private boolean showExpanderForEmptyParent;
/** Data describing the hierarchy information of the tree node being rendered. */
private final TreeNodeData treeNodeData = new TreeNodeData();
/**
* Decorate the component returned from the <code>delegate</code> with
* extra components that display the tree node's location within the tree.
* If <code>delegate</code> is <tt>null</tt> then a
* {@link DefaultTableCellRenderer} will be used as the delegate.
*
* @param delegate the renderer that produces the data for the tree node
* @param treeList the data structure that answers questions about the tree
* node and the tree that contains it
*/
public TreeTableCellRenderer(TableCellRenderer delegate, TreeList treeList) {
this.delegate = delegate == null ? createDelegateRenderer() : delegate;
this.treeList = treeList;
}
/**
* Build the delegate TableCellRenderer that handles rendering the data of
* each tree node.
*/
protected TableCellRenderer createDelegateRenderer() {
return new DefaultTableCellRenderer();
}
/**
* Return a decorated form of the component returned by the data
* {@link TableCellRenderer}.
*/
public Component getTableCellRendererComponent(JTable table, Object value, boolean isSelected, boolean hasFocus, int row, int column) {
treeList.getReadWriteLock().readLock().lock();
try {
// read information about the tree node from the TreeList
treeNodeData.setDepth(treeList.depth(row));
treeNodeData.setExpanded(treeList.isExpanded(row));
treeNodeData.setHasChildren(treeList.hasChildren(row));
treeNodeData.setAllowsChildren(treeList.getAllowsChildren(row));
} finally {
treeList.getReadWriteLock().readLock().unlock();
}
// if the delegate renderer accepts TreeNodeData, give it
if (delegate instanceof TreeTableNodeDataRenderer)
((TreeTableNodeDataRenderer) delegate).setTreeNodeData(treeNodeData);
// ask the delegate renderer to produce the data component
final Component c = delegate.getTableCellRendererComponent(table, value, isSelected, hasFocus, row, column);
// fetch the number of pixels to indent
final int indent = getIndent(treeNodeData, showExpanderForEmptyParent);
// fetch the number of pixels to space over
final int spacer = getSpacer(treeNodeData, showExpanderForEmptyParent);
// ask our special component to configure itself for this tree node
component.configure(treeNodeData, showExpanderForEmptyParent, c, hasFocus, indent, spacer);
return component;
}
/**
* Returns the number of pixels to indent the contents of the renderer.
*
* @param treeNodeData hierarhical information about the node within the tree
* @param showExpanderForEmptyParent <tt>true</tt> indicates the expander
* button should always be present, even when no children yet exist
*/
protected int getIndent(TreeNodeData treeNodeData, boolean showExpanderForEmptyParent) {
return UIManager.getIcon("Tree.expandedIcon").getIconWidth() * treeNodeData.getDepth();
}
/**
* Returns the number of pixels of space between the expand/collapse button
* and the node component.
*
* @param treeNodeData hierarhical information about the node within the tree
* @param showExpanderForEmptyParent <tt>true</tt> indicates the expander
* button should always be present, even when no children yet exist
*/
protected int getSpacer(TreeNodeData treeNodeData, boolean showExpanderForEmptyParent) {
return 2;
}
/**
* If <code>b</code> is <tt>true</tt> then the expand/collapse button must
* be displayed for nodes which allow children but do not currently have
* children. This implies that empty tree nodes with the
* <strong>potential</strong> for children may be displayed differently
* than pure leaf nodes which are guaranteed to never have children.
*/
void setShowExpanderForEmptyParent(boolean b) {
showExpanderForEmptyParent = b;
}
/**
* Use the given <code>delegate</code> to render the data associated with
* each tree node.
*/
void setDelegate(TableCellRenderer delegate) {
this.delegate = delegate;
}
/**
* Returns the delegate TableCellRenderer being decorated.
*/
public TableCellRenderer getDelegate() {
return delegate;
}
/**
* Cleanup the data within this renderer as it is no longer being used and
* must be prepared for garbage collection.
*/
public void dispose() {
delegate = null;
treeList = null;
}
}