/// <summary>Handles touch events for dragging.</summary>
/// <remarks>
/// Handles touch events for dragging. You may want to do other actions
/// like moving the cursor on touch as well.
/// </remarks>
public static bool onTouchEvent (TextView widget, Spannable buffer, MotionEvent @event)
{
DragState[] ds;
switch (@event.getActionMasked ()) {
case MotionEvent.ACTION_DOWN:
{
ds = buffer.getSpans<DragState> (0, buffer.Length);
{
for (int i = 0; i < ds.Length; i++) {
buffer.removeSpan (ds [i]);
}
}
buffer.setSpan (new DragState (@event.getX (), @event.getY (), widget.getScrollX (), widget.getScrollY ()), 0, 0, SpannedClass.SPAN_MARK_MARK);
return true;
}
case MotionEvent.ACTION_UP:
{
ds = buffer.getSpans<DragState> (0, buffer.Length);
{
for (int i_1 = 0; i_1 < ds.Length; i_1++) {
buffer.removeSpan (ds [i_1]);
}
}
if (ds.Length > 0 && ds [0].mUsed) {
return true;
} else {
return false;
}
goto case MotionEvent.ACTION_MOVE;
}
case android.view.MotionEvent.ACTION_MOVE:
{
ds = buffer.getSpans<Touch.DragState> (0, buffer.Length);
if (ds.Length > 0) {
if (ds [0].mFarEnough == false) {
int slop = ViewConfiguration.get (widget.getContext ()).getScaledTouchSlop ();
if (Math.Abs (@event.getX () - ds [0].mX) >= slop || Math.Abs (@event.getY () - ds [0].mY) >= slop) {
ds [0].mFarEnough = true;
}
}
if (ds [0].mFarEnough) {
ds [0].mUsed = true;
bool cap = (@event.getMetaState () & KeyEvent.META_SHIFT_ON) != 0 ||
MetaKeyKeyListener.getMetaState (buffer, MetaKeyKeyListener.META_SHIFT_ON) == 1 ||
MetaKeyKeyListener.getMetaState (buffer, MetaKeyKeyListener.META_SELECTING) != 0;
float dx;
float dy;
if (cap) {
// if we're selecting, we want the scroll to go in
// the direction of the drag
dx = @event.getX () - ds [0].mX;
dy = @event.getY () - ds [0].mY;
} else {
dx = ds [0].mX - @event.getX ();
dy = ds [0].mY - @event.getY ();
}
ds [0].mX = @event.getX ();
ds [0].mY = @event.getY ();
int nx = widget.getScrollX () + (int)dx;
int ny = widget.getScrollY () + (int)dy;
int padding = widget.getTotalPaddingTop () + widget.getTotalPaddingBottom ();
Layout layout = widget.getLayout ();
ny = Math.Min (ny, layout.getHeight () - (widget.getHeight () - padding));
ny = Math.Max (ny, 0);
int oldX = widget.getScrollX ();
int oldY = widget.getScrollY ();
scrollTo (widget, layout, nx, ny);
// If we actually scrolled, then cancel the up action.
if (oldX != widget.getScrollX () || oldY != widget.getScrollY ()) {
widget.cancelLongPress ();
}
return true;
}
}
return false;
}
}
return false;
}
