public void calculateCurrentPage() {
if (pageComponents != null) {
Rectangle viewport = scrollpane.getViewport().getViewRect();
// find visible pages
ArrayList<PageViewComponent> visiblePages = new ArrayList<PageViewComponent>(10);
Rectangle pageBounds;
int pageCount = 0;
for (AbstractPageViewComponent pageComponent : pageComponents) {
if (pageComponent != null) {
pageBounds = documentViewModel.getPageBounds(pageCount);
if (pageBounds != null && pageComponent.isShowing()) {
visiblePages.add(pageComponent);
}
}
pageCount++;
}
// find center point of view port
int x = viewport.x + (viewport.width / 2);
int y = viewport.y + (viewport.height / 2);
Point centerView = new Point(x, y);
// find out which page center is closest to center and thus the new current page
double minLength = Double.MAX_VALUE;
int minPage = -1;
double tmpDistance;
for (PageViewComponent pageComponent : visiblePages) {
if (pageComponent != null) {
pageBounds = documentViewModel.getPageBounds(pageComponent.getPageIndex());
x = pageBounds.x + (pageBounds.width / 2);
y = pageBounds.y + (pageBounds.height / 2);
// find minimum page.
tmpDistance = centerView.distance(x, y);
if (tmpDistance < minLength) {
minLength = tmpDistance;
minPage = pageComponent.getPageIndex();
}
}
}
// clean up
visiblePages.clear();
visiblePages.trimToSize();
// finally send out event to update page number
int oldCurrentPage = documentViewModel.getViewCurrentPageIndex();
documentViewModel.setViewCurrentPageIndex(minPage);
DocumentViewControllerImpl documentViewController =
(DocumentViewControllerImpl) documentView.getParentViewController();
documentViewController.firePropertyChange(
PropertyConstants.DOCUMENT_CURRENT_PAGE, oldCurrentPage, minPage);
}
}
public void mouseClicked(MouseEvent e) {
if ((e.getModifiers() & MouseEvent.MOUSE_PRESSED) != 0) {
if ((e.getModifiers() & InputEvent.BUTTON1_MASK) != 0) {
// zoom in
Point pageOffset =
documentViewModel.getPageBounds(pageViewComponent.getPageIndex()).getLocation();
Point mouse = e.getPoint();
mouse.setLocation(pageOffset.x + mouse.x, pageOffset.y + mouse.y);
documentViewController.setZoomOut(mouse);
}
}
if (pageViewComponent != null) {
pageViewComponent.requestFocus();
}
}