public void layout(IFigure parent) {
ScrollPane scrollpane = (ScrollPane)parent;
Rectangle clientArea = parent.getClientArea();
ScrollBar hBar = scrollpane.getHorizontalScrollBar(),
vBar = scrollpane.getVerticalScrollBar();
Viewport viewport = scrollpane.getViewport();
Insets insets = new Insets();
insets.bottom = hBar.getPreferredSize(clientArea.width, clientArea.height).height;
insets.right = vBar.getPreferredSize(clientArea.width, clientArea.height).width;
int hVis = scrollpane.getHorizontalScrollBarVisibility(),
vVis = scrollpane.getVerticalScrollBarVisibility();
Dimension available = clientArea.getSize(),
preferred =
viewport.getPreferredSize(available.width, available.height).getCopy();
boolean none = available.contains(preferred),
both = !none && vVis != NEVER && hVis != NEVER && preferred.contains(available),
showV = both || preferred.height > available.height,
showH = both || preferred.width > available.width;
//Adjust for visibility override flags
showV = !(vVis == NEVER) && (showV || vVis == ALWAYS);
showH = !(hVis == NEVER) && (showH || hVis == ALWAYS);
if (!showV) insets.right = 0;
if (!showH) insets.bottom = 0;
Rectangle bounds, viewportArea = clientArea;
if (showV) {
bounds = new Rectangle(
viewportArea.right() - insets.right,
viewportArea.y, insets.right, viewportArea.height);
vBar.setBounds(bounds);
}
if (showH) {
bounds = new Rectangle(viewportArea.x,
viewportArea.bottom() - insets.bottom,
viewportArea.width, insets.bottom);
hBar.setBounds(bounds);
}
vBar.setVisible(showV);
hBar.setVisible(showH);
viewport.setBounds(viewportArea);
}