Various small fixes

* Correctly hide network stream button in the theme background page.
* Fix traceback in the FTW due to the mainwindow (which is not yet created) being used.

openlp/core/lib/ui.py

@@ -115,7 +115,12 @@ def critical_error_message_box(title=None, message=None, parent=None, question=F
         return QtWidgets.QMessageBox.critical(parent, UiStrings().Error, message,
                                               QtWidgets.QMessageBox.StandardButtons(QtWidgets.QMessageBox.Yes |
                                                                                     QtWidgets.QMessageBox.No))
-    return Registry().get('main_window').error_message(title if title else UiStrings().Error, message)
+    # If used before the main window is created, fall back to direct use of QMessageBox
+    main_window = Registry().get('main_window')
+    if main_window:
+        return main_window.error_message(title if title else UiStrings().Error, message)
+    else:
+        QtWidgets.QMessageBox.critical(parent, title, message)
 
 
 def create_horizontal_adjusting_combo_box(parent, name):

openlp/core/pages/background.py

@@ -150,7 +150,7 @@ class BackgroundPage(GridLayoutPage):
         self.stream_color_button.setObjectName('stream_color_button')
         self.layout.addWidget(self.stream_color_button, 7, 1)
         self.stream_widgets = [self.stream_label, self.stream_lineedit, self.device_stream_select_button,
-                               self.stream_color_label, self.stream_color_button]
+                               self.network_stream_select_button, self.stream_color_label, self.stream_color_button]
         # Force everything up
         self.layout_spacer = QtWidgets.QSpacerItem(1, 1)
         self.layout.addItem(self.layout_spacer, 8, 0, 1, 4)

openlp/core/threading.py

@@ -67,7 +67,9 @@ def run_thread(worker, thread_name, can_start=True):
     thread.started.connect(worker.start)
     worker.quit.connect(thread.quit)
     worker.quit.connect(worker.deleteLater)
-    worker.error.connect(main_window.error_message)
+    # when used from the FTW the main window is not yet available
+    if main_window:
+        worker.error.connect(main_window.error_message)
     thread.finished.connect(thread.deleteLater)
     thread.finished.connect(make_remove_thread(thread_name))
     if can_start:

openlp/core/ui/firsttimeform.py

@@ -219,10 +219,10 @@ class FirstTimeForm(QtWidgets.QWizard, UiFirstTimeWizard, RegistryProperties):
             self.application.process_events()
         except Exception:
             log.exception('Unable to parse sample config file %s', web_config)
-            critical_error_message_box(
+            QtWidgets.QMessageBox.critical(self, translate('OpenLP.FirstTimeWizard', 'Invalid index file'),
-                translate('OpenLP.FirstTimeWizard', 'Invalid index file'),
+                                           translate('OpenLP.FirstTimeWizard',
-                translate('OpenLP.FirstTimeWizard', 'OpenLP was unable to read the resource index file. '
+                                                     'OpenLP was unable to read the resource index file. '
-                                                    'Please try again later.'))
+                                                     'Please try again later.'))
             return False
         return True
 

openlp/plugins/songs/lib/importer.py

@@ -289,7 +289,11 @@ class SongFormat(object):
             'prefix': 'liveWorship',
             'selectMode': SongFormatSelect.SingleFile,
             'filter': '{text} (*.xml)'.format(text=translate('SongsPlugin.ImportWizardForm',
-                                                             'LiveWorship Database'))
+                                                             'LiveWorship Database')),
+            'descriptionText': translate('SongsPlugin.ImportWizardForm',
+                                         'First convert your LiveWorship database to an XML text file, as '
+                                         'explained in the <a href="http://manual.openlp.org/songs.html'
+                                         '#importing-from-liveworship">User Manual</a>.')
         },
         Lyrix: {
             'class': LyrixImport,

tests/functional/openlp_core/ui/test_firsttimeform.py

@@ -278,8 +278,8 @@ def test_on_custom_button_clicked_internet_settings(mocked_proxy_dialog):
     mocked_proxy_dialog().exec.assert_called_once()
 
 
-@patch('openlp.core.ui.firsttimeform.critical_error_message_box')
+@patch('openlp.core.ui.firsttimeform.QtWidgets.QMessageBox')
-def test__parse_config_invalid_config(mocked_critical_error_message_box):
+def test__parse_config_invalid_config(mocked_message_box):
     """
     Test `FirstTimeForm._parse_config` when called with invalid data
     """
@@ -291,7 +291,9 @@ def test__parse_config_invalid_config(mocked_critical_error_message_box):
 
     # THEN: _parse_data should return False and the user should have should have been informed.
     assert result is False
-    mocked_critical_error_message_box.assert_called_once()
+    mocked_message_box.critical.assert_called_once_with(
+        first_time_form, 'Invalid index file',
+        'OpenLP was unable to read the resource index file. Please try again later.')
 
 
 @patch('openlp.core.ui.firsttimeform.get_web_page')