Method clearItems

3rdparty/qcustomplot/qcustomplot.cpp:14597–14603

! Removes all items from the plot and deletes them. Returns the number of items removed. \see removeItem */

  \see removeItem
*/
int QCustomPlot::clearItems()
{
  int c = mItems.size();
  for (int i=c-1; i >= 0; --i)
    removeItem(mItems[i]);
  return c;
}

/*!
  Returns the number of currently existing items in the plot