Boon is an alternative to curses. It occupies a similar level of abstraction (somewhere between terminfo and your application), but uses different concepts. It is just over 100loc and has no dependencies outside the standard library.
The high level API aims to be declarative and is partly inspired by react. The lines of the terminal are represented as a list of strings. On each update, this list is regenerated and compared to the previous version. Only the lines that have changed are rendered to the terminal.
Boon does not provide utilities for color and styling. You can either use the low level API or a third party library such as colorama or blessings.
pip install boon-term
import boon
class Example(boon.App):
def render(self, rows, cols):
yield 'Hello World'
def on_key(self, key):
if key == 'q':
self.running = False
example = Example()
example.run()
Call to start the main loop.
Set to False
to stop the main loop.
An instance of
selectors.DefaultSelector
you can use to register additional file objects to the main loop.
Overwrite to define your view. For every line in the UI, this functions should yield a string.
Overwrite to react to key presses. key
is a string containing either a
character or an escape sequence. Boon contains constants for the most common
escape sequences:
KEY_BACKSPACE
KEY_ESC
KEY_HOME
KEY_END
KEY_DEL
KEY_PPAGE
KEY_NPAGE
KEY_UP
KEY_DOWN
KEY_RIGHT
KEY_LEFT
Get a capability from the terminfo database. If stdout is not a tty or if the capability is not supported by the terminal this returns an empty string. The full list of capabilities is available in the terminfo manpage
print(get_cap('setaf', 13) + 'foo' + get_cap('sgr0'))
Move the cursor to the given position.
Context manager that restores tty settings after the nested block.
def getpass(prompt):
fd = sys.stdin.fileno()
with tty_restore(fd):
flags = termios.tcgetattr(fd)
flags[3] &= ~termios.ECHO
termios.tcsetattr(fd, termios.TCSADRAIN, flags)
return input(prompt)
Context manager that enters cup and cbreak mode and also hides the cursor. Everything is restored to the previous state after the nested block.
Read from stdin. See App.on_key()
for details on the return value.