Code
class RowSelectionTree extends JTree {
private static final Color SELC = new Color(100, 150, 200);
private Handler handler;
@Override protected void paintComponent(Graphics g) {
g.setColor(getBackground());
g.fillRect(0, 0, getWidth(), getHeight());
if (getSelectionCount() > 0) {
g.setColor(SELC);
for (int i : getSelectionRows()) {
Rectangle r = getRowBounds(i);
g.fillRect(0, r.y, getWidth(), r.height);
}
}
super.paintComponent(g);
if (getLeadSelectionPath() != null) {
Rectangle r = getRowBounds(getRowForPath(getLeadSelectionPath()));
g.setColor(hasFocus() ? SELC.darker() : SELC);
g.drawRect(0, r.y, getWidth() - 1, r.height - 1);
}
}
@Override public void updateUI() {
removeFocusListener(handler);
super.updateUI();
setUI(new BasicTreeUI() {
@Override public Rectangle getPathBounds(JTree tree, TreePath path) {
if (tree != null && treeState != null) {
return getPathBounds(path, tree.getInsets(), new Rectangle());
}
return null;
}
private Rectangle getPathBounds(
TreePath path, Insets insets, Rectangle bounds) {
Rectangle rect = treeState.getBounds(path, bounds);
if (rect != null) {
rect.width = tree.getWidth();
rect.y += insets.top;
}
return rect;
}
});
handler = new Handler();
addFocusListener(handler);
setCellRenderer(handler);
setOpaque(false);
}
static class Handler extends DefaultTreeCellRenderer implements FocusListener {
@Override public Component getTreeCellRendererComponent(
JTree tree, Object value, boolean selected, boolean expanded,
boolean leaf, int row, boolean hasFocus) {
JLabel l = (JLabel) super.getTreeCellRendererComponent(
tree, value, selected, expanded, leaf, row, hasFocus);
l.setBackground(selected ? SELC : tree.getBackground());
l.setOpaque(true);
return l;
}
@Override public void focusGained(FocusEvent e) {
e.getComponent().repaint();
}
@Override public void focusLost(FocusEvent e) {
e.getComponent().repaint();
}
}
}
References
