init qrscanner processor in scan_qr

gui/qt/main_window.py

@@ -2144,12 +2144,6 @@ class ElectrumWindow(QMainWindow):
 
     def read_tx_from_qrcode(self):
         from electrum import qrscanner
-        if qrscanner.proc is None:
-            try:
-                qrscanner.init(self.config)
-            except Exception, e:
-                QMessageBox.warning(self, _('Error'), _(e), _('OK'))
-                return
         try:
             data = qrscanner.scan_qr(self.config)
         except BaseException, e:

gui/qt/qrtextedit.py

@@ -53,17 +53,11 @@ class ScanQRTextEdit(QRTextEdit):
 
     def qr_input(self):
         from electrum import qrscanner
-        if qrscanner.proc is None:
-            try:
-                qrscanner.init(self.win.config)
-            except Exception, e:
-                QMessageBox.warning(self, _('Error'), _(e), _('OK'))
-                return
         try:
             data = qrscanner.scan_qr(self.win.config)
         except BaseException, e:
             QMessageBox.warning(self, _('Error'), _(e), _('OK'))
-            return
+            return ""
         if type(data) != str:
             return
         self.setText(data)

lib/qrscanner.py

@@ -8,21 +8,18 @@ except ImportError:
 
 proc = None
 
-def init(config):
+
+def scan_qr(config):
+    global proc
     if not zbar:
         raise BaseException("\n".join([_("Cannot start QR scanner."),_("The zbar package is not available."),_("On Linux, try 'sudo apt-get install python-zbar'")]))
+    if proc is None:
         device = config.get("video_device", "default")
         if device == 'default':
             device = ''
-    global proc
         proc = zbar.Processor()
         proc.init(video_device=device)
 
-def scan_qr(self):
-    if not zbar:
-        raise BaseException("\n".join([_("Cannot start QR scanner."),_("The zbar package is not available."),_("On Linux, try 'sudo apt-get install python-zbar'")]))
-    if proc is None:
-        raise BaseException("Start proc first")
     proc.visible = True
     while True:
         try: