/// <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);
}