High contrast mode
A high contrast mode supports people with low vision. On Microsoft Windows systems, high contrast mode is available from the Control Panel; in the Ease of Access Center in Windows 7 and equivalent facilities in other versions of Windows.
To detect high contrast mode in Java™, use the
IlvSwingUtil.isHighContrastMode utility. The high contrast mode affects all standard Swing GUI elements (
JPanel,
JButton, and so on). Custom Swing elements might need special code to adapt to high contrast mode.
You can set larger fonts for labels and brighter colors for graphic objects in the JViews Framework, but it does not provide a one-step API to toggle the high contrast mode on. To support a high contrast mode in your application, set the view background appropriately and iterate over all objects to set their colors, fonts, and sizes, as illustrated in the following code example:
void setHighContrast(IlvManager manager, IlvManagerView mgrview, boolean on)
{
// set the selection handle color to light or dark depending on the mode
manager.deSelectAll(true);
IlvHandlesSelection.defaultHandleColor =
on ? new Color(180,180,255) : Color.black;
//the view background
mgrview.setBackground(on ? Color.black : Color.white);
Font normalContrastFont = new Font("dialog", "bold", 12);
Font highContrastFont = new Font("dialog", "bold", 16);
IlvGraphicEnumeration e = grapher.getObjects(true);
while (e.hasMoreElements()) {
IlvGraphic g = e.nextElement();
if (g instanceof IlvText) {
IlvText text = (IlvText)g;
text.setForeground(on ? Color.white : Color.black);
text.setFont(on ? highContrastFont : normalContrastFont);
} else if (g instanceof ...) {
... other adaptions for other graphic objects ...
}
}
mgrview.repaint();
}
You can find a sample that illustrates the accessibility features of the JViews Framework in <installdir>/jviews-frameworkxx/samples/accessibility.
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