http://www.techradar.com/pro/linux March 2020 LXF260 89

Python & Qt5 CODING ACADEMY

Figure 2: Qt 5

Designer’s New

Form Dialog.

You want to

choose Dialog

without Buttons.

GITSTATUS.PY METHODS

shown in Figure 4.

GitStatusDialog.ui is an XML file. We’re going to use

the pyuic5 tool to convert it to a Python file. At the

command line type:

pyuic5 -x -o gitStatus.py GitStatusDialog.ui.

We’re now going to edit gitStatus.py, so be careful not

to run the previous command again or you’ll overwrite

your Python file.

Before we edit gitStatus.py, let’s see what pyuic5

gave us. At the command line type:

python3 gitStatus.py

You should see the empty dialog. Clicking

pushButtonClose should close the application, since

we’ve already hooked up the signal and slot for that

button. pyuic5 created a working dialog that doesn’t

really do anything.

GitStatus.py should now contain the class

Ui_GitStatus. The class should have two methods:

setupUi(self, gitStatus) and retranslateUi(self, gitStatus).

The -x option in pyuic5 also created a main section for

our project.

Now, you’ll add some functionality to gitStatus.py.

Open up gitStaus.py in your text editor. Add #!/usr/bin/

env python3 as the first line in the program. This tells

Bash that if we ask it to execute gitStatus.py, it will load

Python 3 to do it. In order for that to happen, we need to

set the flag that tells Bash that gitStatus.py is an

executable program. At the command line, type:

chmod +x gitStatus.py

Go back to your editor and add the signals and slots

for pushButtonRefresh, listWidgetRepo and

listWidgetStatus. At the end of the method

retranslateUi(self, GitStatus) add the following lines:

# hook up signals (widget outputs) and slots (class

member methods)

self.listWidgetRepo.itemSelectionChanged.

connect(self.repoSelectionChanged)

self.listWidgetStatus.itemSelectionChanged.

connect(self.statusSelectionChanged)

self.pushButtonRefresh.clicked.connect(self.refresh).

Now add the methods that we want to call when

pushButtonRefresh is clicked or the selection is

changed in listWidgetRepo or listWidgetStatus:

def refresh(self): # pushButtonRefresh has been

clicked

def repoSelectionChanged(self): # listWidgetRepo

selection changed

def statusSelectionChanged(self): # listWidgetStatus

selection changed

Populate these functions by copying the code from

gitStatus.py.original. Continue adding methods to

gitStatus.py. There is a lot of code to copy. If you’re

building gitStatus.py from scratch, open gitStatus.

py.original in your code editor and copy the code from

there. You need to add the methods shown in the boxout

(see right).

The program works by initially searching for git

repositories, determining their default colour (red,

orange or green) by invoking the git status --porcelain

command, populating and then alphabetising

listWidgetRepo. This happens in the method

populateDialog(). We call populateDialog() once in

main(), before the dialog is visible. We also call

populateDialog() when pushButtonRefresh is clicked.

Every time listWidgetRepo’s selected working

directory is changed, and it is changed when we first

populate listWidgetRepo, the selectionChanged()

method is called. That’s where we call git and get all of

the modified, deleted, added, removed or untracked

files in the selected working directory. We determine the

colour for each issue that git status reports, and then

we populate listWidgetStatus with that information.

The first thing we do is to construct a QApplication

object with any options passed to main() on the

command line. This occurs in line 466 of gitStatus.py:

app = Qapplication(sys.argv)

We then set the application’s name and version for the

QCommandLineParser class in lines 467 and 468:

clp = QcommandLineParser()

This handles the --help, --version, and the --verbose

command line options. This is all taken care of for us by

the clp.process(sys.argv) statement in line 476.

We then construct our dialog in line 478:

GitStatus = QtWidgets.Qdialog() # construct QDialog

ui = Ui_GitStatus() # instantiate ui

ui.setupUi(GitStatus) # configure all widgets

ui.isVerbose = clp.isSet(verboseOption)

We now call the parseConfigFile() function to read

gitStatus.ini, which is located in the same directory as

gitStatus.py. If gitStatus.ini is not found,

parseConfigFile() will create gitStatus.ini and make

Methods to be added to gitStatus.py:

hasGitDir(self, dir): returns True if dir has a subdirectory .git.

appendSlash(self, str): appends / to str if str doesn’t end with /.

quickCheckPriority(self, dir): uses git status --porcelain. It returns

COLOR_RED for modified files, COLOR_ORANGE for deleted, added,

copied or untracked files, else COLOR_GREEN.

refresh(self): This is the SLOT for the pushButtonRefresh clicked

signal. It clears and repopulates the dialog.

statusSelectionChanged(self): when listWidgetStatus selection has

changed. Sets a stylesheet for the selected item in listWidgetStatus.

repoSelectionChanged(self): when listWidgetRepo selection has

changed. Sets a stylesheet for the selected item in listWidgetRepo.

Also invokes git status --porcelain to populate listWidgetStatus.

populateDialog(self): fills in all the fields of the dialog. Searches

disk(s) for directories containing git repositories and populates

listWidgetRepo accordingly.

parseConfigFile(self): reads or creates gitStatus.ini and determines

the searched directories and the directories we want to ignore.

main: parses command line options and instantiates, populates and

shows the dialog.

You can run ,

which will create

gitStatus.html. If

you have LAMP

server on your

system, copy

gitStatus.html

to /srv/www/

htdocs and

serve it up using

apache2. Open

a browser and

select localhost/

gitStatus.html

in the address

bar. /srv/

www/htdocs

is the location

apache2 uses to

serve files in our

distro. Search

for htdocs to

find where it is

on your system.

888March 202 Mcdisu dsePyQt March 2020 LXF260 89

Python & Qt5 CODING ACADEMY

Figure 2: Qt 5

Designer’s New

Form Dialog.

You want to

choose Dialog

without Buttons.

GITSTATUS.PY METHODS

shown in Figure 4.
GitStatusDialog.ui is an XML file. We’re going to use
the pyuic5 tool to convert it to a Python file. At the
command line type:
pyuic5 -x -o gitStatus.py GitStatusDialog.ui.
We’re now going to edit gitStatus.py, so be careful not
to run the previous command again or you’ll overwrite
your Python file.
Before we edit gitStatus.py, let’s see what pyuic5
gave us. At the command line type:
python3 gitStatus.py
You should see the empty dialog. Clicking
pushButtonClose should close the application, since
we’ve already hooked up the signal and slot for that
button. pyuic5 created a working dialog that doesn’t
really do anything.
GitStatus.py should now contain the class
Ui_GitStatus. The class should have two methods:
setupUi(self, gitStatus) and retranslateUi(self, gitStatus).
The -x option in pyuic5 also created a main section for
our project.
Now, you’ll add some functionality to gitStatus.py.
Open up gitStaus.py in your text editor. Add #!/usr/bin/
env python3 as the first line in the program. This tells
Bash that if we ask it to execute gitStatus.py, it will load
Python 3 to do it. In order for that to happen, we need to
set the flag that tells Bash that gitStatus.py is an
executable program. At the command line, type:
chmod +x gitStatus.py
Go back to your editor and add the signals and slots
for pushButtonRefresh, listWidgetRepo and
listWidgetStatus. At the end of the method
retranslateUi(self, GitStatus) add the following lines:

hook up signals (widget outputs) and slots (class

member methods)
self.listWidgetRepo.itemSelectionChanged.
connect(self.repoSelectionChanged)
self.listWidgetStatus.itemSelectionChanged.
connect(self.statusSelectionChanged)
self.pushButtonRefresh.clicked.connect(self.refresh).
Now add the methods that we want to call when
pushButtonRefresh is clicked or the selection is
changed in listWidgetRepo or listWidgetStatus:
defrefresh(self):#pushButtonRefreshhasbeen
clicked
defrepoSelectionChanged(self): # listWidgetRepo
selection changed
def statusSelectionChanged(self): # listWidgetStatus
selection changed
Populate these functions by copying the code from
gitStatus.py.original. Continue adding methods to
gitStatus.py. There is a lot of code to copy. If you’re
building gitStatus.py from scratch, open gitStatus.
py.original in your code editor and copy the code from
there. You need to add the methods shown in the boxout
(see right).
The program works by initially searching for git
repositories, determining their default colour (red,
orange or green) by invoking the git status --porcelain
command, populating and then alphabetising
listWidgetRepo. This happens in the method
populateDialog(). We call populateDialog() once in
main(), before the dialog is visible. We also call
populateDialog() when pushButtonRefresh is clicked.
Every time listWidgetRepo’s selected working

directory is changed, and it is changed when we first

populate listWidgetRepo, the selectionChanged()

method is called. That’s where we call git and get all of

the modified, deleted, added, removed or untracked

files in the selected working directory. We determine the

colour for each issue that git status reports, and then

we populate listWidgetStatus with that information.

The first thing we do is to construct a QApplication

object with any options passed to main() on the

command line. This occurs in line 466 of gitStatus.py:

app = Qapplication(sys.argv)

We then set the application’s name and version for the

QCommandLineParser class in lines 467 and 468:

clp = QcommandLineParser()

This handles the --help, --version, and the --verbose

command line options. This is all taken care of for us by

the clp.process(sys.argv) statement in line 476.

We then construct our dialog in line 478:

GitStatus= QtWidgets.Qdialog()#constructQDialog

ui= Ui_GitStatus()# instantiate ui

ui.setupUi(GitStatus) # configure all widgets

ui.isVerbose = clp.isSet(verboseOption)

We now call the parseConfigFile() function to read

gitStatus.ini, which is located in the same directory as

gitStatus.py. If gitStatus.ini is not found,

parseConfigFile() will create gitStatus.ini and make

MethodstobeaddedtogitStatus.py:

hasGitDir(self,dir):returnsTrueifdirhasasubdirectory.git.

appendSlash(self,str):appends/tostrifstrdoesn’tendwith/.

quickCheckPriority(self, dir): uses git status --porcelain. It returns

COLOR_REDformodifiedfiles,COLOR_ORANGEfordeleted,added,

copiedoruntrackedfiles,elseCOLOR_GREEN.

refresh(self):ThisistheSLOTforthepushButtonRefreshclicked

signal.Itclearsandrepopulatesthedialog.

statusSelectionChanged(self):whenlistWidgetStatusselectionhas

changed.SetsastylesheetfortheselectediteminlistWidgetStatus.

repoSelectionChanged(self): when listWidgetRepo selection has

changed.SetsastylesheetfortheselectediteminlistWidgetRepo.

Alsoinvokesgitstatus--porcelaintopopulatelistWidgetStatus.

populateDialog(self): fills in all the fields of the dialog. Searches

disk(s)fordirectoriescontaininggitrepositoriesandpopulates

listWidgetRepoaccordingly.

parseConfigFile(self):readsorcreatesgitStatus.inianddetermines

thesearcheddirectoriesandthedirectorieswewanttoignore.

main: parses command line options and instantiates, populates and

shows the dialog.

Youcanrun,

whichwillcreate

gitStatus.html.If

youhaveLAMP

serveronyour

system,copy

gitStatus.html

to/srv/www/

htdocsand

serveit upusing

apache2.Open

a browserand

selectlocalhost/

gitStatus.html

intheaddress

bar./srv/

www/htdocs

isthelocation

apache2usesto

servefilesinour

distro.Search

forhtdocsto

findwhereit is

onyoursystem.