Pops up this widget at the inputed position.  The inputed point should \
        be in global space.
        
        :param      pos | <QPoint>
        
        :return     <bool> success

def popup(self, pos=None):
        """
        Pops up this widget at the inputed position.  The inputed point should \
        be in global space.
        
        :param      pos | <QPoint>
        
        :return     <bool> success
        """
        if self._first and self.centralWidget() is not None:
            self.adjustSize()
            self._first = False
        
        if not self.signalsBlocked():
            self.aboutToShow.emit()
        
        if not pos:
            pos = QCursor.pos()
        
        if self.currentMode() == XPopupWidget.Mode.Dialog and \
             self.isVisible():
            return False
        
        elif self.currentMode() == XPopupWidget.Mode.Dialog:
            self.setPopupMode()
        
        # auto-calculate the point
        if self.autoCalculateAnchor():
            self.setAnchor(self.mapAnchorFrom(self.parent(), pos))
        
        pad = self.popupPadding()
        
        # determine where to move based on the anchor
        anchor = self.anchor()
        
        # MODIFY X POSITION
        # align x-left
        if ( anchor & (XPopupWidget.Anchor.TopLeft |
                       XPopupWidget.Anchor.BottomLeft) ):
            pos.setX(pos.x() - pad)
        
        # align x-center
        elif ( anchor & (XPopupWidget.Anchor.TopCenter |
                         XPopupWidget.Anchor.BottomCenter) ):
            pos.setX(pos.x() - self.width() / 2)
        
        # align x-right
        elif ( anchor & (XPopupWidget.Anchor.TopRight |
                         XPopupWidget.Anchor.BottomRight) ):
            pos.setX(pos.x() - self.width() + pad)
        
        # align x-padded
        elif ( anchor & (XPopupWidget.Anchor.RightTop |
                         XPopupWidget.Anchor.RightCenter |
                         XPopupWidget.Anchor.RightBottom) ):
            pos.setX(pos.x() - self.width())
        
        # MODIFY Y POSITION
        # align y-top
        if ( anchor & (XPopupWidget.Anchor.LeftTop |
                       XPopupWidget.Anchor.RightTop) ):
            pos.setY(pos.y() - pad)
        
        # align y-center
        elif ( anchor & (XPopupWidget.Anchor.LeftCenter |
                         XPopupWidget.Anchor.RightCenter) ):
            pos.setY(pos.y() - self.height() / 2)
        
        # align y-bottom
        elif ( anchor & (XPopupWidget.Anchor.LeftBottom |
                         XPopupWidget.Anchor.RightBottom) ):
            pos.setY(pos.y() - self.height() + pad)
        
        # align y-padded
        elif ( anchor & (XPopupWidget.Anchor.BottomLeft |
                         XPopupWidget.Anchor.BottomCenter |
                         XPopupWidget.Anchor.BottomRight) ):
            pos.setY(pos.y() - self.height())
        
        self.adjustMask()
        self.move(pos)
        self.update()
        self.setUpdatesEnabled(True)
        
        if self.isAnimated():
            anim = QPropertyAnimation(self, 'windowOpacity')
            anim.setParent(self)
            anim.setStartValue(0.0)
            anim.setEndValue(self.windowOpacity())
            anim.setDuration(500)
            anim.finished.connect(anim.deleteLater)
            self.setWindowOpacity(0.0)
        else:
            anim = None
            
        
        self.show()
        
        if self.currentMode() != XPopupWidget.Mode.ToolTip:
            self.activateWindow()
            
            widget = self.centralWidget()
            if widget:
                self.centralWidget().setFocus()
            
        
        if anim:
            anim.start()
        
        if not self.signalsBlocked():
            self.shown.emit()
        
        return True