Ricardo Borges

Personal blog

How I open and resize all my applications with just a keyboard shortcut

Every morning I have to open, resize and reposition all applications I need to work, so I thought: What if I only had to press a keyboard shortcut that could do that for me...

To make this happen I would need to write a script that will be executed by that shortcut, this script would have to do three tasks: Open applications, wait for it to start, and resize and reposition them.

Before continuing, this was developed and tested on Pop!_OS 20.04 LTS, a Ubuntu-based Linux distro. The source code is here. I could just use suspend mode, but I use dual boot, so that doesn't always work for me, and exploring other tools to find a solution is way more fun.

This script was written in Python 3.8, I called it desktop-bootstrap.py, to open the applications I used the subprocess module. And to resize and reposition I used the command line tool wmctrl. The script accepts arguments, so you can open one application at a time, but it also supports a configuration file to open a set of applications, I'll cover in this article the latter approach.

In each line of the configuration file, you write the application you want to open, the command to open it, size and position, like this:

<command> <Application name> <X Axios> <Y Axios> <Window width> <Window height>

An example of a configuration file would be:

1insomnia insomnia 960 0 960 1080
2google-chrome google 0 0 960 1080 https://dev.to/ricardo93borges https://github.com/ricardo93borges

Note that most browsers accept as arguments the websites to open when it starts, each website open in a different tab, so we'll take advantage of that. You can name the configuration file as config-sample.txt.

Now we need a shell script that will be executed when we use the keyboard shortcut, this shell script will call the python script passing as an argument the location of the configuration file. I want to open a terminal too, so I also included the command to do so in the shell script:

1# desktop-bootstrap.sh
2
3#!/bin/sh
4gnome-terminal --geometry 170x25+1920+890 --working-directory=/home
5/usr/bin/python3.8 /path/to/desktop-bootstrap.py --file /path/to/config-sample.txt

Here is the python script with comments to explain some pieces of the code:

1# desktop-bootstrap.py
2
3import subprocess
4import time
5import sys
6
7"""
8I limited the retries, so the script doesn't run 
9forever waiting for an application to start 
10"""
11max_retries = 20
12
13"""
14This method get an application ID looking for its name 
15in a list obtained by a wmctrl command, 
16that ID is used in the resize command
17"""
18def get_id_by_name(applications_running, name):
19    for app in applications_running:
20        if app.lower().find(name) > -1:
21            return app.split(' ')[0]
22
23"""
24This method receives a list of applications and 
25for each one check if is running. If is running resize and 
26reposition it, if not check again in the next iteration
27"""
28def resize(applications):
29    retry = 0
30    while len(applications) > 0:
31# Get a list of running applications
32        applications_running = subprocess.check_output(["wmctrl", "-lp"]).decode("utf-8").split("\n")
33        for index, app in enumerate(applications):
34            application_id = get_id_by_name(applications_running, app['name'])
35            if application_id:
36# Resize and reposition
37                dimensions = "-e " f"0,{app['x']},{app['y']},{app['width']},{app['height']}"
38                command = ["wmctrl", "-i", "-r", application_id, dimensions]
39                subprocess.run(command)
40                applications.pop(index)
41
42        retry += 1
43        if retry > max_retries:
44            break
45
46        time.sleep(5)
47
48"""
49This method open the application and send it to 
50resize() method to resize and reposition it 
51accordingly to the arguments passed
52"""
53def handle_args():
54    command = [sys.argv[1]]
55
56"""
57If the application is a browser it may have more 
58arguments (the websites to open when it starts)
59"""
60    for i in range(len(sys.argv) - 7):
61        command.append(sys.argv[7 + i])
62
63    output = subprocess.Popen(command)
64
65    applications = [{
66        'name': sys.argv[2],
67        'pid': output.pid,
68        'x': sys.argv[3],
69        'y': sys.argv[4],
70        'width': sys.argv[5],
71        'height': sys.argv[6]
72        }]
73
74    resize(applications)
75
76"""
77This method handles the configuration file, open 
78the applications and send it to resize() method 
79to resize and reposition it.
80"""
81def handle_file(file):
82    applications = []
83    with open(file) as f:
84        for index, line in enumerate(f):
85            props = line.split(' ')
86            command = [props[0]]
87
88"""
89If the application is a browser it may have 
90more arguments (the websites to open when it starts)
91"""
92            for i in range(len(props) - 6):
93                command.append(props[6+i])
94
95            output = subprocess.Popen(command)
96            applications.append({
97                'name': props[1],
98                'pid': output.pid,
99                'x': props[2],
100                'y': props[3],
101                'width': props[4],
102                'height': props[5]
103            })
104    resize(applications)
105
106"""
107Main method, check the arguments and call the 
108appropriated method to process the applications.
109"""
110def run():
111    if len(sys.argv) > 2:
112        if sys.argv[1] == "--file":
113            handle_file(sys.argv[2])
114        else:
115            handle_args()
116    else:
117        print("\nInvalid number of arguments")
118        print("\nUse the following arguments: ")
119        print("\n<command> <Application name> <X Axios> <Y Axios> <Window width> <Window height>")
120        print("\nOr: ")
121        print("\n--file <path/to/configuration/file>")
122
123    sys.exit(0)
124
125
126run()

Finally, we'll create the keyboard shortcut, this may differ from one Linux distribution to another, in Pop_OS! 20.04 you open settings menu go to keyboard shortcuts, then scroll down to the bottom of the list of shortcuts and click on the + button. In the window that launched you set a name for the shortcut, in the command input you type the path to that shell script (desktop-bootstrap.sh), for example: /home/ricardo/workspace/desktop-bootstrap/desktop-bootstrap.sh. In shortcut, you choose the combinations of keys that will execute the shell script.

And that's it, you can find more details on this repository.