RPA.Desktop

Desktop is a cross-platform library for navigating and interacting with desktop environments. It can be used to automate applications through the same interfaces that are available to human users.

The library includes the following features:

• Mouse and keyboard input emulation
• Starting and stopping applications
• Finding elements through image template matching
• Scraping text from given regions
• Taking screenshots
• Clipboard management

Installation

The basic features such as mouse and keyboard input and application control work with a default rpaframework install.

Advanced computer-vision features such as image template matching and OCR require an additional library called rpaframework-recognition.

The dependency should be added separately by specifing it in your conda.yaml as rpaframework-recognition==5.0.1 for example. If installing recognition through pip instead of conda, the OCR feature also requires tesseract.

Locating elements

To automate actions on the desktop, a robot needs to interact with various graphical elements such as buttons or input fields. The locations of these elements can be found using a feature called locators.

A locator describes the properties or features of an element. This information can be later used to locate similar elements even when window positions or states change.

The currently supported locator types are:

Name	Arguments	Description
alias	name (str)	A custom named locator from the locator database, the default.
image	path (str)	Image of an element that is matched to current screen content.
point	x (int), y (int)	Pixel coordinates as absolute position.
offset	x (int), y (int)	Pixel coordinates relative to current mouse position.
size	width (int), height (int)	Region of fixed size, around point or screen top-left
region	left (int), top (int), right (int), bottom (int)	Bounding coordinates for a rectangular region.
ocr	text (str), confidence (float, optional)	Text to find from the current screen.

A locator is defined by its type and arguments, divided by a colon. Some example usages are shown below. Note that the prefix for alias can be omitted as its the default type.

Click       point:50,100
Click       region:20,20,100,30

Move mouse  image:%{ROBOT_ROOT}/logo.png
Move mouse  offset:200,0
Click

Click       alias:SpareBin.Login
Click       SpareBin.Login

Click       ocr:"Create New Account"

You can also pass internal region objects as locators:

${region}=  Find Element  ocr:"Customer name"
Click       ${region}

Locator chaining

Often it is not enough to have one locator, but instead an element is defined through a relationship of various locators. For this use case the library supports a special syntax, which we will call locator chaining.

An example of chaining:

# Read text from area on the right side of logo
Read text    image:logo.png + offset:600,0 + size:400,200

The supported operators are:

Operator	Description
then, +	Base locator relative to the previous one
and, &&, &	Both locators should be found
or, ||, |	Either of the locators should be found
not, !	The locator should not be found

Further examples:

# Click below either label
Click    (image:name.png or image:email.png) then offset:0,300

# Wait until dialog disappears
Wait for element    not image:cookie.png

Named locators

The library supports storing locators in a database, which contains all of the required fields and various bits of metadata. This enables having one source of truth, which can be updated if a website's or applications's UI changes. Robot Framework scripts can then only contain a reference to a stored locator by name.

The main way to create named locators is with VSCode.

Read more on identifying elements and crafting locators:

• Desktop automation and RPA
• How to find user interface elements using locators and keyboard shortcuts in Windows applications

Keyboard and mouse

Keyboard keywords can emulate typing text, but also pressing various function keys. The name of a key is case-insensitive and spaces will be converted to underscores, i.e. the key Page Down and page_down are equivalent.

The following function keys are supported:

Key	Description
shift	A generic Shift key. This is a modifier.
shift_l	The left Shift key. This is a modifier.
shift_r	The right Shift key. This is a modifier.
ctrl	A generic Ctrl key. This is a modifier.
ctrl_l	he left Ctrl key. This is a modifier.
ctrl_r	The right Ctrl key. This is a modifier.
alt	A generic Alt key. This is a modifier.
alt_l	The left Alt key. This is a modifier.
alt_r	The right Alt key. This is a modifier.
alt_gr	The AltGr key. This is a modifier.
cmd	A generic command button (Windows / Command / Super key). This may be a modifier.
cmd_l	The left command button (Windows / Command / Super key). This may be a modifier.
cmd_r	The right command button (Windows / Command / Super key). This may be a modifier.
up	An up arrow key.
down	A down arrow key.
left	A left arrow key.
right	A right arrow key.
enter	The Enter or Return key.
space	The Space key.
tab	The Tab key.
backspace	The Backspace key.
delete	The Delete key.
esc	The Esc key.
home	The Home key.
end	The End key.
page_down	The Page Down key.
page_up	The Page Up key.
caps_lock	The Caps Lock key.
f1 to f20	The function keys.
insert	The Insert key. This may be undefined for some platforms.
menu	The Menu key. This may be undefined for some platforms.
num_lock	The Num Lock key. This may be undefined for some platforms.
pause	The Pause / Break key. This may be undefined for some platforms.
print_screen	The Print Screen key. This may be undefined for some platforms.
scroll_lock	The Scroll Lock key. This may be undefined for some platforms.

When controlling the mouse, there are different types of actions that can be done. Same formatting rules as function keys apply. They are as follows:

Action	Description
click	Click with left mouse button
left_click	Click with left mouse button
double_click	Double click with left mouse button
triple_click	Triple click with left mouse button
right_click	Click with right mouse button

The supported mouse button types are left, right, and middle.

Examples

Both Robot Framework and Python examples follow.

The library must be imported first.

*** Settings ***
Library    RPA.Desktop

from RPA.Desktop import Desktop
desktop = Desktop()

The library can open applications and interact with them through keyboard and mouse events.

*** Keywords ***
Write entry in accounting
    [Arguments]    ${entry}
    Open application    erp_client.exe
    Click         image:%{ROBOT_ROOT}/images/create.png
    Type text     ${entry}
    Press keys    ctrl    s
    Press keys    enter

def write_entry_in_accounting(entry):
    desktop.open_application("erp_client.exe")
    desktop.click(f"image:{ROBOT_ROOT}/images/create.png")
    desktop.type_text(entry)
    desktop.press_keys("ctrl", "s")
    desktop.press_keys("enter")

Targeting can be currently done using coordinates (absolute or relative), but using template matching is preferred.

*** Keywords ***
Write to field
    [Arguments]  ${text}
    Move mouse   image:input_label.png
    Move mouse   offset:200,0
    Click
    Type text    ${text}
    Press keys   enter

def write_to_field(text):
    desktop.move_mouse("image:input_label.png")
    desktop.move_mouse("offset:200,0")
    desktop.click()
    desktop.type_text(text)
    desktop.press_keys("enter")

Elements can be found by text too.

*** Keywords ***
Click New
    Click       ocr:New

def click_new():
    desktop.click('ocr:"New"')

It is recommended to wait for the elements to be visible before trying any interaction. You can also pass region objects as locators.

*** Keywords ***
Click New
    ${region}=  Wait For element  ocr:New
    Click       ${region}

def click_new():
    region = desktop.wait_for_element("ocr:New")
    desktop.click(region)

Another way to find elements by offsetting from an anchor:

*** Keywords ***
Type Notes
    [Arguments]        ${text}
    Click With Offset  ocr:Notes  500  0
    Type Text          ${text}

def type_notes(text):
    desktop.click_with_offset("ocr:Notes", 500, 0)
    desktop.type_text(text)