code: def exportItemChanged(self, item, prev):
      if item is None:
          return
      if item.gitem is self.scene:
          newBounds = self.scene.views()[0].viewRect()
      else:
          newBounds = item.gitem.sceneBoundingRect()
      self.selectBox.setRect(newBounds)
      self.selectBox.show()
      self.updateFormatList()
  
imports: from ..None import exporters
  from ..None import functions
  from ..graphicsItems.PlotItem import PlotItem
  from ..graphicsItems.ViewBox import ViewBox
  from ..Qt import QtCore, QtWidgets
  from .None import exportDialogTemplate_generic
label_desc: Use image node_id 5 for calling the ExportDialog obj's underlying member method code with example usage: obj.exportItemChanged(item, prev) without return types