JLabel optimized for usage in renderers and
* with a minimal background painter support. * * Note: the painter support will be switched to painter_work as * soon it enters main. * * The reasoning for the performance-overrides is copied from core:
*
* The standard JLabel component was not
* designed to be used this way and we want to avoid
* triggering a revalidate each time the
* cell is drawn. This would greatly decrease performance because the
* revalidate message would be
* passed up the hierarchy of the container to determine whether any other
* components would be affected.
* As the renderer is only parented for the lifetime of a painting operation
* we similarly want to avoid the overhead associated with walking the
* hierarchy for painting operations.
* So this class
* overrides the validate, invalidate,
* revalidate, repaint, and
* firePropertyChange methods to be
* no-ops and override the isOpaque method solely to improve
* performance. If you write your own renderer component,
* please keep this performance consideration in mind.
*
* * @author Jeanette Winzenburg */ public class JRendererLabel extends JLabel implements PainterAware { protected Painter painter; /** * */ public JRendererLabel() { super(); setOpaque(true); } /** * Overridden for performance reasons.
* PENDING: Think about Painters and opaqueness? * */ @Override public boolean isOpaque() { Color back = getBackground(); Component p = getParent(); if (p != null) { p = p.getParent(); } // p should now be the JTable. boolean colorMatch = (back != null) && (p != null) && back.equals(p.getBackground()) && p.isOpaque(); return !colorMatch && super.isOpaque(); // PENDING JW: Issue #1188-swingx: problems with background in Synth // basically a core issue - nevertheless, evaluate implications of // a simple straight-forward implemenation - return the property // no tricks // return super.isOpaque(); } /** * {@inheritDoc} */ public void setPainter(Painter painter) { Painter old = getPainter(); this.painter = painter; firePropertyChange("painter", old, getPainter()); } /** * {@inheritDoc} */ public Painter getPainter() { return painter; } /** * {@inheritDoc}
* * Overridden to inject Painter's painting.
* TODO: cleanup logic - see JRendererCheckBox. * */ @Override protected void paintComponent(Graphics g) { // JW: hack around for #1178-swingx (core issue) // grab painting if Nimbus detected if ((painter != null) || isNimbus()) { // we have a custom (background) painter // try to inject if possible // there's no guarantee - some LFs have their own background // handling elsewhere if (isOpaque()) { // replace the paintComponent completely paintComponentWithPainter((Graphics2D) g); } else { // transparent apply the background painter before calling super paintPainter(g); super.paintComponent(g); } } else { // nothing to worry about - delegate to super super.paintComponent(g); } } /** * Hack around Nimbus not respecting background colors if UIResource. * So by-pass ... * * @return */ private boolean isNimbus() { return UIManager.getLookAndFeel().getName().contains("Nimbus"); } /** * * Hack around AbstractPainter.paint bug which disposes the Graphics. * So here we give it a scratch to paint on.
* TODO - remove again, the issue is fixed? * * @param g the graphics to paint on */ private void paintPainter(Graphics g) { if (painter == null) return; // fail fast: we assume that g must not be null // which throws an NPE here instead deeper down the bowels // this differs from corresponding core implementation! Graphics2D scratch = (Graphics2D) g.create(); try { painter.paint(scratch, this, getWidth(), getHeight()); } finally { scratch.dispose(); } } // public void setStrictWidth(boolean strict) { // this.strict = strict; // } // // @Override // public Dimension getMaximumSize() { // if (strict) { // return super.getMaximumSize(); // } // Dimension max = super.getMaximumSize(); // max.width = Integer.MAX_VALUE - 1; // return max; // } /** * PRE: painter != null, isOpaque() * @param g */ protected void paintComponentWithPainter(Graphics2D g) { // 1. be sure to fill the background // 2. paint the painter // by-pass ui.update and hook into ui.paint directly if (ui != null) { // fail fast: we assume that g must not be null // which throws an NPE here instead deeper down the bowels // this differs from corresponding core implementation! Graphics2D scratchGraphics = (Graphics2D) g.create(); try { scratchGraphics.setColor(getBackground()); scratchGraphics.fillRect(0, 0, getWidth(), getHeight()); paintPainter(g); ui.paint(scratchGraphics, this); } finally { scratchGraphics.dispose(); } } } /** * {@inheritDoc}
* * Overridden to not automatically de/register itself from/to the ToolTipManager. * As rendering component it is not considered to be active in any way, so the * manager must not listen. */ @Override public void setToolTipText(String text) { putClientProperty(TOOL_TIP_TEXT_KEY, text); } /** * Overridden for performance reasons. * See the Implementation Note * for more information. * * @since 1.5 */ @Override public void invalidate() {} /** * Overridden for performance reasons. * See the Implementation Note * for more information. */ @Override public void validate() {} /** * Overridden for performance reasons. * See the Implementation Note * for more information. */ @Override public void revalidate() {} /** * Overridden for performance reasons. * See the Implementation Note * for more information. */ @Override public void repaint(long tm, int x, int y, int width, int height) {} /** * Overridden for performance reasons. * See the Implementation Note * for more information. */ @Override public void repaint(Rectangle r) { } /** * Overridden for performance reasons. * See the Implementation Note * for more information. * * @since 1.5 */ @Override public void repaint() { } /** * Overridden for performance reasons. * See the Implementation Note * for more information. */ @Override protected void firePropertyChange(String propertyName, Object oldValue, Object newValue) { // Strings get interned... if ("text".equals(propertyName)) { super.firePropertyChange(propertyName, oldValue, newValue); } } /** * Overridden for performance reasons. * See the Implementation Note * for more information. */ @Override public void firePropertyChange(String propertyName, boolean oldValue, boolean newValue) { } }