It depends on the view mode, for single/dual view mode, you can achieve that by modifying PDFLayoutView.onTouchNone and PDFGestureListener.onFling as follows:
private boolean onTouchNone(MotionEvent event)
{....
case MotionEvent.ACTION_MOVE:
if(m_hold && m_layout.vGetScale() > m_layout.vGetMinScale()) {
m_layout.vSetX((int) (m_hold_docx + m_hold_x - event.getX()));
m_layout.vSetY((int) (m_hold_docy + m_hold_y - event.getY()));
invalidate();
}
break;
case MotionEvent.ACTION_UP:
case MotionEvent.ACTION_CANCEL:
if(m_hold && m_layout.vGetScale() > m_layout.vGetMinScale()) {....class PDFGestureListener extends GestureDetector.SimpleOnGestureListener
{
@Override
public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY)
{
if(m_layout == null) return false;
if(m_status == STA_NONE && m_hold && m_layout.vGetScale() > m_layout.vGetMinScale())
{....This will block the scroll and fling while the page is not zoomed.
If you need to block the page change while zoomed, please check
Avoid page change during navigation while zoomed (Android)
