fix pylint error "(undefined-variable) Undefined variable 'X'"

fix problem happend when tests are running under python-coverage

$ python-coverage run ./tests/tools/test_application.py

Exception while connecting LOCAL://!
Traceback (most recent call last):
File "/home/developer/WorkData/PLC/beremiz/beremiz/ProjectController.py", line 1753, in _Connect
self._SetConnector(connectors.ConnectorFactory(uri, self)
File "/home/developer/WorkData/PLC/beremiz/beremiz/ProjectController.py", line 1702, in _SetConnector
if connector is not None:
PyAssertionError: C++ assertion "m_window" failed at ../src/gtk/dcclient.cpp(2043) in DoGetSize(): GetSize() doesn't work without window

fix pylint error '(too-many-function-args) Too many positional arguments for function call'

fix pylint error '(import-error) Unable to import X'

fix pylint error '(no-self-argument) Method should have "self" as first argument'

fix pylint error "(no-name-in-module) No name 'X' in module 'Y'"

fix pylint error '(bad-except-order) Bad except clauses order (X is an ancestor class of Y)'

fix pylint warning "(no-value-for-parameter) No value for argument 'X' in function call"

fix problems with unconnected input of InOut function variables and
enfoce InOut variables to be connected for functions and function blocks

fix error for functions with VAR_IN_OUT

The problem was found by pylint '(used-before-assignment) Using variable "X" before assignment'

fix pylint warning '(unidiomatic-typecheck) Using type() instead of isinstance() for a typecheck'

fix pylint warning '(misplaced-bare-raise) The raise statement is not inside an except clause'

fix format string argument error found by pylint '(too-many-format-args) Too many arguments for format string'

fix pylint warning '(wrong-import-position) Import "import X" should be placed at the top of the module'

fix pylint warning '(import-self) Module import itself'

remove old code useless code found by pylint "(unnecessary-pass) Unnecessary pass statement"

fix error found by pylint 'W0104(pointless-statement) Statement seems to have no effect'

fix pylint warning "(undefined-loop-variable) Using possibly undefined loop variable 'X'"

fix pylint warning 'C0112(empty-docstring) Empty function docstring'

fix pylint warning "(relative-import) Relative import 'Y', should be 'X.Y'"

fix pylint warning '(dangerous-default-value) Dangerous default value {} as argument'

fix pylint warning '(old-style-class) Old-style class defined.'

This warning is ignored for classes from PyJSLib, because library
overrides base object class.

fix pylint warning '(unused-import), Unused import connectors'

fix typos

comment out unused code SFC_Step.RefreshBoundingBox()

explicitly mark unused variables found by pylint with _ or dummy

pylint don't ignores unused variables with '_' in the name, even when
they are started with '_'. This bug is already fixed upstream, to fix
this in all versions of pylint custom dummy-variables-rgx is used
'_+$|(_[a-zA-Z0-9_]*[a-zA-Z0-9]+?$)|dummy'

remove unused variables found by pylint

update .PHONE target in Makefile for mki18n.py

make mki18n return 0 on success

update list with files for internatialization, app.fil

move README content to Makefile

It's not necessary to copy commands from README anymore. Just use
'make source_list', 'make template' or 'make locales'.

fix pylint warning '(global-variable-not-assigned) Using global for 'X' but no assignment is done'

fix pylint error '(function-redefined) method already defined'

fix pylint warning '(unreachable) Unreachable code'

fix pylint warning (bad-indentation) Bad indentation. Found X spaces, expected Y

fix pylint warning '(pointless-string-statement) String statement has no effect'

Python doesn't support docstring for variables directly. Where
appropriate Sphinx style for docstrings for variables is used
'#: some-docstring'

fix error __init__ method from base class is not called

fix more than one statement on a single line

fix ungrouped imports from package X

fix unnecessary lambda and enable corresponding pylint check

fix wrong-import-order. first standard modules are imported, then others

fix (old-style-class) Old-style class defined error for most parts of
the code

only PyJS code is left, because it does some fancy tricks and can't be
easily fixed. So far PyJS doesn't support Python3 anyway.

remove in-tree version of Zeroconf and use upstream from
python-zeroconf package

remove reimported modules

fix unnecessary parens after keyword

enable pylint checker

so far only print statement is checked

fix usage of python2-only print statement

run python tests with non-english locale to catch bugs related to localization

make it possible to update XSD schema in project controller after new
target PLC is added or removed.

For example:


...
import targets
targets.targets["PLC"] = {"xsd": os.path.join(self.customBeremizPath, "PLCtarget", xsd),
"class": lambda: PLC_target,
"code": {"plc_PLC_main.c": os.path.join(self.customBeremizPath, "PLCtarget", "plc_PLC_main.c")}
}

from ProjectController import ProjectController, GetProjectControllerXSD
ProjectController.XSD = GetProjectControllerXSD()

fix commit "lazy initialization of highlight pens and brushes
for DebugVariableViewer" (5562f34f)

clean build example project after running test

fix problem if DataTypeEditor was imported before localization is
loaded

That doesn't affect systems with english locales.

add shell script to run all python tests and automatically handle Xvfb

add PLCOpenEditor tests

run application tests in full screen mode

clean sys.argv, because if test is running from pytest
sys.argv contains string "pytest --timeout 0 ./tests/tools"
Beremiz application parses it and throws exception.

rework Beremiz application "testCheckProject" test to allow easier reuse later

add application name for PLCOpenEditor

This is needed to work user configuration load/store, if PLCOpenEditor
is launched from test environment.

rewrite PLCOpenEditor. Add PLCOpenEditorApp class for easier customizations.

lazy locale initialization

wx.Locale() can't be called without wx.App. So don't call it at
import. It makes PLCOpenEditor simpler.

use CustomIntCtrl instead of wx.SpinCtrl because it doesn't support
long integer needed for UDINT, (U)LINT types.

This commit complements commit 74a3f4d "fix LINT and ULINT ranges".

add custom TextCtrl allowed to enter long integer with bounds checking

It's needed because wx.SpinCtrl supports only 'int' type. For UDINT
and (U)LINT long type is necessary.

use pytest for testing

run separate test on every project instead of one big long test all projects

move configuration for test environment into separate file conftest.py

lazy initialization of highlight pens and brushes for DebugVariableViewer

Constructors wx.Pen() and wx.Brush() require wx.App to exist already.
That causes crash during import of the control,
because import is done before calling main application code.

add '_' function to builtin dictionary at import time

This allows to import many Beremiz python modules before calling
util.misc.InstallLocalRessources().

remove builtin BMZ_DBG. It's not used.

update translation strings

updated all existing translations
added new languages: Portuguese (Portugal), Italian, Hungarian,
Spanish and Bengali. See version.py for information about translators.

fix LINT and ULINT ranges

found installed Inkscape on Windows

tested with Inkscape version 0.9 on Windows 7.

make possible to turn off at compile time online debugging, logging
and external sync functionality

Defines TARGET_DEBUG_DISABLE, TARGET_LOGGING_DISABLE, TARGET_EXT_SYNC_DISABLE
allow to use generated PLC code in low-cost microcontrollers,
integrate into external programs and so on.

main.c:
extern void __run(void);
int main(void)
{
for(;;) {
__run();
// sleep common_ticktime__ ns
// add common_ticktime__ ns to __CURRENT_TIME
}
return 0;
}

Compile for example for arm bare-metal:
../build$ arm-none-eabi-gcc \
-DTARGET_DEBUG_DISABLE -DTARGET_LOGGER_DISABLE
-DTARGET_EXT_SYNC_DISABLE \
-flto -ffunction-sections -fdata-sections -I../../../../matiec/lib/C \
*.c \
-nodefaultlibs --specs=nano.specs -Wl,--static -Wl,--gc-section -Wl,--start-group -lc -lm -lnosys -lgcc -Wl,--end-group

make default caption for PouNameDialog translatable

fix max value for UDINT and ULINT types

update Build icon

add couple Beremiz application tests

These tests trigger around 45% of python code.
Used in tests docker files are avaiable here:
https://bitbucket.org/skvorl/beremiz-dockerfiles

fix problem if _should_write is called by expired timer after
termination of wx application.

Initial Bitbucket Pipelines configuration

fix bug with unfinished debug thread
this bug occurs when user doesn't stop debugging process in current project, and opens another project

unify exception handling of Beremiz and PLCOpenEditor

fix problem running PLCOpenEditor

$ ./PLCOpenEditor.py
../src/common/stdpbase.cpp(62): assert "traits" failed in Get(): create wxApp before calling this

Regression was introduced by '3311eea' (clean-up: fix PEP8 E402 module level import not at top of file)

don't check any particular wx version

Beremiz works with any version of wx.

fix problem when Beremiz is running without matiec installed

set matiec settings only once on first use of ProjectController class and give
user-friendly message on compilation about missing matiec
installation.


Traceback (most recent call last):
File "Beremiz.py", line 197, in <module>
beremiz.Start()
File "Beremiz.py", line 192, in Start
self.CreateApplication()
File "Beremiz.py", line 130, in CreateApplication
self.BackgroundInitialization()
File "Beremiz.py", line 137, in BackgroundInitialization
self.ImportModules()
File "Beremiz.py", line 176, in ImportModules
import BeremizIDE
File
"BeremizIDE.py", line 76, in <module>
from ProjectController import ProjectController, GetAddMenuItems,
MATIEC_ERROR_MODEL, ITEM_CONFNODE
File
"ProjectController.py", line 177, in <module>
iec2c_cfg = Iec2CSettings()
File
"ProjectController.py", line 101, in __init__
self.ieclib_c_path = self.findLibCPath()
File
"ProjectController.py", line 135, in findLibCPath
os.path.join(self.ieclib_path, "C"),
File "/usr/lib/python2.7/posixpath.py", line 70, in join
elif path == '' or path.endswith('/'):
AttributeError: 'NoneType' object has no attribute 'endswith'

Initial Bitbucket Pipelines configuration

add configuration for Bitbucket pipelines

add shell script to test Beremiz python code

currently only codestyle checking is done using pycodestyle (ex-pep8).
Later checks by flake8 and pylint maybe enabled.

clean-up: fix PEP8 W503 line break before binary operator

fix codestyle issues according to PEP8

clean-up: fix PEP8 E402 module level import not at top of file

clean-up: fix PEP8 E265 block comment should start with '# '

clean-up: fix PEP8 E266 too many leading '#' for block comment

clean-up: fix PEP8 E722 do not use bare except'

better it'd be to use particular exception instead of 'except Exception'.

clean-up: fix PEP8 E115 expected an indented block (comment)

clean-up: fix PEP8 E721 do not compare types, use 'isinstance()'

clean-up: fix PEP8 E131 continuation line unaligned for hanging indent

clean-up: fix PEP8 E122 continuation line missing indentation or outdented

clean-up: fix PEP8 E713 test for membership should be 'not in'

clean-up: fix PEP8 E272 multiple spaces before keyword

clean-up: fix PEP8 E124 closing bracket does not match visual indentation

clean-up: fix PEP8 W191 indentation contains tabs

clean-up: fix PEP8 E211 whitespace before '[' or '('

clean-up: fix PEP8 E114 indentation is not a multiple of four (comment)

clean-up: fix PEP8 E125 continuation line with same indent as next logical line

clean-up: fix PEP8 E128 continuation line under-indented for visual indent

clean-up: fix PEP8 E127 continuation line over-indented for visual indent

clean-up: fix PEP8 E129 visually indented line with same indent as next logical line

clean-up: fix PEP8 W602 deprecated form of raising exception

clean-up: fix PEP8 E502 the backslash is redundant between brackets

clean-up: fix PEP8 W601 .has_key() is deprecated, use 'in'

clean-up: fix PEP8 E731 do not assign a lambda expression, use a def

clean-up: fix PEP8 E203 whitespace before ','

clean-up: fix PEP8 E262 inline comment should start with '# '

clean-up: fix PEP8 E712 comparison to True should be 'if cond is True:' or 'if cond:'

clean-up: fix PEP8 E222 multiple spaces after operator

clean-up: fix PEP8 E111 indentation is not a multiple of four

clean-up: fix PEP8 E701 multiple statements on one line (colon)

clean-up: fix PEP8 E741 ambiguous variable name

clean-up: fix most PEP8 E221 multiple spaces before operator

clean-up: fix most PEP8 E266 too many leading '#' for block comment

clean-up: fix PEP8 E703 statement ends with a semicolon

clean-up: fix PEP8 E301 expected 1 blank line, found 0

clean-up: fix PEP8 E306 expected 1 blank line before a nested definition, found X

clean-up: fix PEP8 E305 expected 2 blank lines after class or function definition

clean-up: fix PEP8 W391 blank line at end of file

clean-up: fix PEP8 E201 whitespace after '{'

clean-up: fix PEP8 E202 whitespace before ')'

clean-up: fix PEP8 E227 missing whitespace around bitwise or shift operator

clean-up: fix PEP8 E251 unexpected spaces around keyword / parameter equals

clean-up: fix PEP8 E711 comparison to None should be 'if cond is not None:'

clean-up: fix PEP8 E225 missing whitespace around operator

clean-up: fix PEP8 E303 too many blank lines

clean-up: fix PEP8 E231 missing whitespace after ':' or ','

clean-up: fix PEP8 E203 whitespace before ':' and whitespace before ','

clean-up: fix PEP8 E271 multiple spaces after keyword

clean-up: fix PEP8 E261 at least two spaces before inline comment

clean-up: fix PEP8 E302 expected 2 blank lines, found 1

clean-up: fix PEP8 W293 blank line contains whitespace

clean-up: fix some PEP8 E228 missing whitespace around modulo operator

clean-up: fix some PEP8 E265 block comment should start with '# '

clean-up: fix PEP8 E401 multiple imports on one line

convert some files from CRLF to LF

It'll break for these files hg blame/annotate. Fortunately not many
files are affected.

clean-up for PEP8: fix W291 trailing whitespace

README.md edited online with Bitbucket

fix link to documentation in README.md

Add information about built official documentation to README.md

don't allow empty dimension for ARRAY types

ignore built documentation

manual: add untranslated po files for French and Korean

build missing pot files, when building HTML documentation

fix some typos

Changed title of new project dialog from:
Choose a project
to
Choose an empty directory for new project

Changed title of New Project dialog
from
Chose a project
to
Choose an empty directory for new project

skip hidden files and directories on permission check

To fix problems with git, because .git subdirectory contains
read-only repository objects.

change structure of filename for bug reports in Beremiz and
PLCOpenEditor so bug reports could be easily sorted by name

fix target Xenomai missing functions

update messages.pot and messages.po

mki18n.py: generate messages.po (contains English strings in msgstr)

This po file is necessary because Transifex translation platform
automatically can only import PO files. Usually messages.pot is
enough.

add to i18n/README forgotten commands to add some XML schemes as source
for strings and update app.fil

Backout commit 92537ed because of writing localized string in node *.xml file

Backout changeset 92537edeb2052d53ba5cad8b6da8463dbc660bb1

fixes double mouse capturing after forcing variable in debug mode
this problem appears on Linux

fix bug with TextViewer instance in debug mode, appears after transferring new program on PLC
TextViewer isn't able to display debug values, so calling for this class SubscribeAllDataConsumers method causes error

fix build problem when make command have trailing whitespace(s)

whitespaces at the end are replaced with "", that causes make problem

add dialog "add program", that appears after creating new project
also, sets one task and one instance of created program in main project resource

fix i18n string selection for combobox generated from XSD

update Russian and French (Fabien M) translations
added Slovenian (Janez Pregelj) and Portuguese (Thiago Alves) translations

l18n: update messages.pot and app.fil

add l18n support to variable table in CodeFileEditor (python/C extension)

set project name and character set in generated messages.pot

close DurationEditorDialog on ENTER key

add button to ForceVariableDialog to toggle forced boolean value

Button is added only for boolean variables.

fix problem with hidden FindInPou dialog with wxPython 3.0 on Windows

FindInPou.IsShown() returned True, but dialog was hidden.
At same time On GNU/Linux with wxPython 3.0 there wasn't such problem.
So it's Windows specific.

enable non-latin variable descriptions in CodeFileEditor

fix following backtrace:

UnicodeEncodeError: 'ascii' codec can't encode characters in position 0-7: ordinal not in range(128)
Traceback (most recent call last):
File "beremiz/editors/CodeFileEditor.py", line 610, in GetValue
return str(self.data[row].get(self.GetColLabelValue(col, False), ""))
UnicodeEncodeError: 'ascii' codec can't encode characters in position 0-7: ordinal not in range(128)

disable empty coils and contacts in LD/SFC editors

Closes #30

remove debug code

make all dialog have non-fixed size

this fixes the problem, that some controls may be hidden in some cases, because
dialog size is too small. This can happen when system fonts are bigger
than expected, default system them controls are bigger or if localized
strings are bigger than in English.

avoid infinite loop in search

for example following regexp '()' creates infinite list of result

make adjustable size of ArrayTypeDialog

fix problem with initial values for array of structures

for structures wrong empty repetition attributes were generated

add information about community support channel to Beremiz and PLCOpenEditor

cleanup wxHMI example

cleanup wxGlade example

add comments to wiimote example

fix running wxGlade on current Debian systems

wxGlade was moved from python import path to /usr/share/wxglade

rename text field in SVG graphic to match IEC code in svgui example

This caused svgui example to crash.

disallow setting IEC location addresses for TIME, DATE, DT and TOD variables

Size of these types is not defined and depends on the implementation
(IEC 61131-3 2.3.1).

if there is no users matiec installation, then use system path to run iec2c

search for matiec libraries in system path as well

Closes #29

remove child node from add child node menu, if max count of the same type nodes reached

fix reducing groups with ordered elements

fix extra brace

add getCompiler and getLinker methods, to abstract from XSD.
add calc_source_md5 as it's more convenient especially for embedded
targets to add -DPLC_MD5="something" option at compile time than
to mess with editing binary.
add some more helper methods

make run Beremiz and PLCOpen Editor, if full path contain non-lating
characters

There was a problem in About dialog and in project properites tab and
probably in my other places, when str is automatically converted to
unicode string using ascii.
This patch converts str to unicode using proper encoding at the very beggining.

README.md edited online with Bitbucket

fix clearing project name on opening project properties page.

The problem exists only on Windows with wxPython-3.0.

This happens because callback for EVT_KILL_FOCUS for a first text
control (project name) is called just after creating page with project
properties. It happens before initializing text controls from PLCController.

fix problem with debugging external string variables

Debug update stopped if external string variable added to debug
variable panel.

fix problem with clearing non-empty location field after changing type of config variable

introduced by cd9db17 ("clear variable location cell in variable
panel, if variable class or type changed").

Closes #26

fix backtrace on opening program/resource on small screens

Fix regression introduced by f4696d8 ("add stretching to columns Name,
Type, Doc in variable panel").
This problem happens only on wxPython-3.0.

show whether instance of SFC action is currently active or not in its
debug instance view

clean PLC log only if there is something to clean

Otherwise exception happens in Beremiz service.

Traceback (most recent call last):
File "/home/developer/WorkData/PLC/beremiz/beremiz/connectors/PYRO/_init_.py", line 113, in catcher_func
return func(*args, **kwargs)
File "/home/developer/WorkData/PLC/beremiz/beremiz/connectors/PYRO/_init_.py", line 194, in my_local_func
return RemotePLCObjectProxy._getattr_(attrName)(*args, **kwargs)
File "/usr/lib/python2.7/dist-packages/Pyro/core.py", line 381, in _call_
return self._send(self._name, args, kwargs)
File "/usr/lib/python2.7/dist-packages/Pyro/core.py", line 456, in _invokePYRO
return self.adapter.remoteInvocation(name, Pyro.constants.RIF_VarargsAndKeywords, vargs, kargs)
File "/usr/lib/python2.7/dist-packages/Pyro/protocol.py", line 457, in remoteInvocation
return self._remoteInvocation(method, flags, *args)
File "/usr/lib/python2.7/dist-packages/Pyro/protocol.py", line 532, in _remoteInvocation
answer.raiseEx()
File "/usr/lib/python2.7/dist-packages/Pyro/errors.py", line 72, in raiseEx
raise self.excObj
AttributeError: 'PLCObject' object has no attribute '_ResetLogCount'
+--- This exception occured remotely (Pyro) - Remote traceback:
Traceback (most recent call last):
File "/usr/lib/python2.7/dist-packages/Pyro/protocol.py", line 719, in _handleInvocation2
res = obj.Pyro_dyncall(req[1],flags,req[3]) # (method,flags,args)
File "/usr/lib/python2.7/dist-packages/Pyro/core.py", line 108, in Pyro_dyncall
return getattr(self.delegate or self,method) (args,*keywords)
File "/home/developer/WorkData/PLC/beremiz/beremiz/runtime/PLCObject.py", line 101, in ResetLogCount
if self._ResetLogCount is not None:
AttributeError: 'PLCObject' object has no attribute '_ResetLogCount'
+--- End of remote traceback

reset loaded messages counts on new PLC program trasnfer

This fixes the problem that first message from newer PLC program maybe
lost, if it's issued before first PLC log fetching.

Closes #23

add function block to variable panel if fb is added using toolbar

Closes #25

enable to write SFC transition in IL

This commit reverts previous commit 3f3d97be9a9f.
Because the fix for the matiec problem is already upstream
(https://bitbucket.org/mjsousa/matiec/commits/ce026aee03e00c0790948a18bd7b35805457da81)

fix debug button and variable tree generate for actions and transitions in POU instance variable panel
for 'None' type instances(Python POU's, Native, SVGUI, user-defined pou's, etc.) debug button will be disabled. If action or transition instances have opened in instance variable panel,variables from main POU will be loaded. When user press debug button on variable instance in action or transition, instance path to main POU will be used, because all variables of action or transition in instance variable tree belong to main POU.

clear variable location cell in variable panel, if variable class or type changed
if variable class is not local or global, or variable type is not locatable, variable location cell would be empty and read-only

runtime is licensed under LGPLv2.1

make command line help message for Beremiz more verbose

fix typos and small errors in Russian translation

merge Beremiz launcher support

Closes #13

rename BeremizIDELauncher.py to Beremiz.py

rename Beremiz.py to BeremizIDE.py

wrap Beremiz startup code into separate launcher class

this should make it easier to make customized version of Beremiz IDE.
It's easy to add own splash, change version, add/disable extensions
and many other things.

For example:

[----- MyBeremiz.py ------]
#!/usr/bin/env python
from BeremizIDELauncher import BeremizIDELauncher

class MyBeremizIDELauncher(BeremizIDELauncher):
def __init__(self):
BeremizIDELauncher.__init__(self)
self.splashPath = self.Bpath("", "splash.png")

def ShowSplashScreen(self):
# comment next line to disable splash entirely
BeremizIDELauncher.ShowSplashScreen(self)

# change version
import version
version.app_version = "3.141-rc52"

def LoadExtensions(self):
# add/modifine list of extensions
# in self.extensions
BeremizIDELauncher.LoadExtensions(self)

if __name__ == '__main__':
beremiz = MyBeremizIDELauncher()
beremiz.Start()

[-------------------------]

dynamically increase size of dialog window for editing comment block

add hotkeys to open recent projects

For simplicity only last 9 projects are saved.

Alt-F, R, 1 - to open last opened project
Alt-F, R, 2 ...
...
Alt-F, R, 9 ...

fix twice shown error message box, when wrong non-valid IEC identifier entered

It happens when non-valid name for variable name or name of field in
structure entered. This issue is described in details here:
http://trac.wxwidgets.org/ticket/16333

apply constraints to names for tasks and task instances in resource configuration

The same rules as for IEC identifiers are applied.
- no non-lating characters, ...
- no IEC keywords
- check for duplicate names in resource configuration

closes #19

Fix russian translation

Merged skvorl/beremiz into default

add stretching to columns Name, Type, Doc in variable panel

fix SFC Step flush method

fix redraw debug instance tab after transferring new build to PLC. closes #15

1. Deleted .directory file, and added it to .hgignore.
2. Added russian locale .mo file.

Fix russian translation

Merge

Safe

broken code is temporarily blocked
This code used to highlight with green color text in upper-left corner (path to current instance) in debug mode, if current instance active. Only SFC actions are affected. #16

fix exception handling
now only one exception dialog is displayed, if many same type exceptions handled (like in #16), and bug reports files always save after exception, not only after pressing "OK" button in exception dialog, closes #17

change directory for saving Beremiz bug reports from current working directory to TEMP directory.

Correct element size, if block type or variable name is wider than block width.
Previously, if size corrected, element changed position to the right (or down, if height is corrected). Now upper-left corner is fixed.

remove non-existed and not necessary self.logger from detecting options in iec2c

remove Linux target from first_steps example

Then default target on the system will be used.

1.2rc1

closing 1.1 branch

for tests svgui and logging move code from old py_ext.xml to the new pyfile.xml

merge

fix IL jumps highlighting in Text Viewer

change white background for icons in PouInstanceVariablePanel to transparent

in wxPython 2.8 panel has white background and therefore white
background is appropriate, but in wxPython 3.0 panel has grey
background (on GNU/Linux and on Windows).
Transparent background looks good on both wxPython versions and on all platforms.

change white background for project tree element to transparent

because on GNU/Linux project tree has grey background, therefore
white background looks not good.

fix second error message in case of error appearing too early to have a wx frame

fix a side effect of 95ecb26fdc4e