Creating a Swing Dashboard Widget - Part 3 (Transparency)

Now we're talking!

To make the background transparent in Java 6 u10 is simple, just call AWTUtilities.setWindowOpaque(this, false);.

Things for me are more complicated as I'm developing on OSX which doesn't have a u10 build available (Apple are at least a year behind the rest of Java). Luckily OSX has long been able to make Java windows transparent just by setting the window background color a transparent one. Why Sun didn't follow this pattern???

So, to make the JFrame transparent on all platforms:
<br /> private void makeTransparent() {<br /> setUndecorated(true); // remove the window controls<br /> setResizable(false); // remove the resize control<br /><br /> // OSX transparency<br /> setBackground(new Color(0f,0f,0f,0f));<br /><br /> // Non-reflection version for Java 6 SE u10:<br /> // AWTUtilities.setWindowOpaque(this, false);<br /> //<br /> // Reflection version (to compile on Java 1.5):<br /> try<br /> {<br /> Class clazz = Class.forName("com.sun.awt.AWTUtilities");<br /> Method method = clazz.getMethod("setWindowOpaque",<br /> new Class[]{Window.class, Boolean.TYPE});<br /> method.invoke(clazz, new Object[]{this, false});<br /> }<br /> catch (ClassNotFoundException e)<br /> {<br /> // Oh well, not Java 6 u10<br /> } catch (NoSuchMethodException e)<br /> {<br /> } catch (IllegalAccessException e)<br /> {<br /> } catch (InvocationTargetException e)<br /> {<br /> }<br /> }<br />

This gives a distinctly widgetty looking...



OSX is even kinder by allowing this widget to be dragged around, Windows will have to get a special mouse listener later.