Use screen size as upper bound for qr code size

also fix some typing issues

electrum/gui/qml/components/Receive.qml

@@ -200,8 +200,7 @@ Pane {
 
     function createRequest(ignoreGaplimit = false) {
         var qamt = Config.unitsToSats(amount.text)
-        console.log('about to create req for ' + qamt.satsInt + ' sats')
-        if (qamt.satsInt > Daemon.currentWallet.lightningCanReceive) {
+        if (qamt.satsInt > Daemon.currentWallet.lightningCanReceive.satsInt) {
             console.log('Creating OnChain request')
             Daemon.currentWallet.create_request(qamt, message.text, expires.currentValue, false, ignoreGaplimit)
         } else {

electrum/gui/qml/qeapp.py

@@ -153,7 +153,9 @@ class ElectrumQmlApplication(QGuiApplication):
         self.engine = QQmlApplicationEngine(parent=self)
         self.engine.addImportPath('./qml')
 
-        self.qr_ip = QEQRImageProvider()
+        screensize = self.primaryScreen().size()
+
+        self.qr_ip = QEQRImageProvider((7/8)*min(screensize.width(), screensize.height()))
         self.engine.addImageProvider('qrgen', self.qr_ip)
 
         # add a monospace font as we can't rely on device having one

electrum/gui/qml/qeqr.py

@@ -118,20 +118,22 @@ class QEQRParser(QObject):
         return result
 
 class QEQRImageProvider(QQuickImageProvider):
-    def __init__(self, parent=None):
+    def __init__(self, max_size, parent=None):
         super().__init__(QQuickImageProvider.Image)
+        self._max_size = max_size
 
     _logger = get_logger(__name__)
 
     @profiler
     def requestImage(self, qstr, size):
         self._logger.debug('QR requested for %s' % qstr)
-        qr = qrcode.QRCode(version=1, box_size=6, border=2)
+        qr = qrcode.QRCode(version=1, border=2)
         qr.add_data(qstr)
 
-        # calculate best box_size, aim for 400 px
+        # calculate best box_size
+        pixelsize = min(self._max_size, 400)
         modules = 17 + 4 * qr.best_fit()
-        qr.box_size = math.floor(400/(modules+2))
+        qr.box_size = math.floor(pixelsize/(modules+2*2))
 
         qr.make(fit=True)
 

electrum/gui/qml/qewallet.py

@@ -305,21 +305,21 @@ class QEWallet(QObject):
     def lightningBalance(self):
         if not self.isLightning:
             return QEAmount()
-        self._lightningbalance = QEAmount(amount_sat=self.wallet.lnworker.get_balance())
+        self._lightningbalance = QEAmount(amount_sat=int(self.wallet.lnworker.get_balance()))
         return self._lightningbalance
 
     @pyqtProperty(QEAmount, notify=balanceChanged)
     def lightningCanSend(self):
         if not self.isLightning:
             return QEAmount()
-        self._lightningcansend = QEAmount(amount_sat=self.wallet.lnworker.num_sats_can_send())
+        self._lightningcansend = QEAmount(amount_sat=int(self.wallet.lnworker.num_sats_can_send()))
         return self._lightningcansend
 
     @pyqtProperty(QEAmount, notify=balanceChanged)
     def lightningCanReceive(self):
         if not self.isLightning:
             return QEAmount()
-        self._lightningcanreceive = QEAmount(amount_sat=self.wallet.lnworker.num_sats_can_receive())
+        self._lightningcanreceive = QEAmount(amount_sat=int(self.wallet.lnworker.num_sats_can_receive()))
         return self._lightningcanreceive
 
     @pyqtSlot()