if fiat_amount is not None:
self.fiat_e.setText("%.2f"%fiat_amount)
self.btc_e.textEdited.connect(btc_changed)
+ self.btc_e.frozen.connect(lambda: self.fiat_e.setFrozen(self.btc_e.isReadOnly()))
self.win.send_grid.addWidget(self.fiat_e, 4, 3, Qt.AlignHCenter)