better code organization

function parameters should be lowercase

Fix crash on invalid labels import

Added invoice exporting and reduced duplicate code

Better exception handling

removed json module import

some more cleanup

Cleaned up some stuff

Added exporting contacts

gui/qt/util.py

@@ -11,6 +11,7 @@ from PyQt5.QtGui import *
 from PyQt5.QtCore import *
 from PyQt5.QtWidgets import *
 
+from electrum.util import FileImportFailed, FileExportFailed
 if platform.system() == 'Windows':
     MONOSPACE_FONT = 'Lucida Console'
 elif platform.system() == 'Darwin':
@@ -674,6 +675,28 @@ class AcceptFileDragDrop:
     def onFileAdded(self, fn):
         raise NotImplementedError()
 
+def import_meta_gui(electrum_window, title, importer, on_success):
+    filename = electrum_window.getOpenFileName(_("Open {} file").format(title)  , "*.json")
+    if not filename:
+       return
+    try:
+       importer(filename)
+    except FileImportFailed as e:
+       electrum_window.show_critical(str(e))
+    else:
+       electrum_window.show_message(_("Your {} were successfully imported" ).format(title))
+       on_success()
+
+def export_meta_gui(electrum_window, title, exporter):
+    filename = electrum_window.getSaveFileName(_("Select file to save your {}").format(title), 'electrum_{}.json'.format(title), "*.json")
+    if  not filename:
+        return
+    try:
+        exporter(filename)
+    except FileExportFailed as e:
+        electrum_window.show_critical(str(e))
+    else:
+        electrum_window.show_message(_("Your {0} were exported to '{1}'").format(title,str(filename)))
 
 if __name__ == "__main__":
     app = QApplication([])