UI Module

This module is responsible for providing a high-level interface for elements of Curses UI and general user interaction with the app,

class canopen_monitor.ui.Column(name: str, attr_name: str, fmt_fn: callable = <class 'str'>, padding: int = 2)

format(object: any) → str

property header: str

update_length(object: any) → bool

class canopen_monitor.ui.InputPopup(parent: any, header: str = 'Alert', footer: str = 'ESC: close', style: Optional[any] = None, input_len: int = 30)

Input form creates a popup window for retrieving text input from the user

Parameters

• parent – parent ui element

• header – header text of popup window

• footer – footer text of popup window

• style – style of window

• input_len – Maximum length of input text

Type

any

Type

str

Type

str

Type

any

Type

int

_abc_impl = <_abc_data object>

get_value() → str

Get the value of user input without trailing spaces :return: user input value :type: str

read_input(keyboard_input: int) → None

Read process keyboard input (ascii or backspace)

Parameters

keyboard_input – curses input character value from curses.getch

Type

int

toggle() → bool

Toggle window and clear inserted text :return: value indicating whether the window is enabled :type: bool

class canopen_monitor.ui.MessagePane(cols: [Column], types: [MessageType], name: str = '', parent: any = None, height: int = 1, width: int = 1, y: int = 0, x: int = 0, message_table: MessageTable = <canopen_monitor.can.message_table.MessageTable object>)

A derivative of Pane customized specifically to list miscellaneous CAN messages stored in a MessageTable

Parameters

• name (str) – The name of the pane (to be printed in the top left)

• cols (dict) – A dictionary describing the pane layout. The key is the Pane collumn name, the value is a tuple containing the Message attribute to map the collumn to, and the max collumn width respectively.

• selected (bool) – An indicator that the current Pane is selected

• table (MessageTable) – The message table

__check_col_widths(messages: [Message]) → None

Check the width of the message in Pane column.

Parameters

messages (list) – The list of the messages

__draw_header() → None

Draw the table header at the top of the Pane

This uses the cols dictionary to determine what to write

_abc_impl = <_abc_data object>

_reset_scroll_positions() → None

Reset the scroll positions. Initialize the y position to be zero. Initialize the x position to be zero.

clear_messages() → None

Clears the message table for the pane.

draw() → None

Draw all records from the MessageTable to the Pane

resize(height: int, width: int) → None

A wrapper for Pane.resize(). This intercepts a call for a resize in order to upate MessagePane-specific details that change on a resize event. The parent resize() gets called first and then MessagePane’s details are updated.

Parameters

• height (int) – New virtual height

• width (int) – New virtual width

scroll_down(rate: int = 1) → None

This overrides Pane.scroll_up(). Instead of shifting the pad vertically, the slice of messages from the MessageTable is shifted.

Parameters

rate (int) – Number of messages to scroll by

property scroll_limit_x: int

The maximim columns the pad is allowed to shift by when scrolling

property scroll_limit_y: int

The maximim rows the pad is allowed to shift by when scrolling

scroll_up(rate: int = 1) → None

This overrides Pane.scroll_up(). Instead of shifting the pad vertically, the slice of messages from the MessageTable is shifted.

Parameters

rate (int) – Number of messages to scroll by

class canopen_monitor.ui.Pane(parent: Optional[any] = None, height: int = 1, width: int = 1, y: int = 0, x: int = 0, border: bool = True, color_pair: int = 0)

Abstract Pane Class, contains a PAD and a window

Parameters

• v_height (int) – The virtual height of the embedded pad

• v_width (int) – The virtual width of the embedded pad

• d_height (int) – The drawn height of the embedded pad

• d_width (int) – The drawn width of the embedded pad

• border (bool) – A style option for drawing a border around the pane

__reset_draw_dimensions() → None

Reset the pane dimensions. You can change the width and height of the pane.

_abc_impl = <_abc_data object>

add_line(line: str, y: Optional[int] = None, x: Optional[int] = None, bold: bool = False, underline: bool = False, highlight: bool = False, color: Optional[any] = None) → None

Adds a line of text to the Pane and if needed, it handles the process of resizing the embedded pad

Parameters

• line (str) – Text to write to the Pane

• y (int) – Line’s row position

• x (int) – Line’s collumn position

• bold (bool) – A style option to bold the line written

• highlight (bool) – A syle option to highlight the line writte

• style (curses.style) – A color option for the line

clear() → None

Clear all contents of pad and parent window

Warning

This should only be used if an event changing the entire pane occurs. If used on every cycle, a flickering effect will occur, due to the slowness of the operation.

clear_line(y: int, style: Optional[any] = None) → None

Clears a single line of the Pane

Parameters

• y (int) – The line to clear

• style (int) – The background color to set when clearing the line

abstract draw() → None

Abstract draw method, must be overwritten in child class draw should first resize the pad using: super().resize(w, h) then add content using: self._pad.addstr() then refresh using: super().refresh()

abstract method will clear and handle border

child class should also set _scroll_limit_x and _scroll_limit_y here

refresh() → None

Refresh the pane based on configured draw dimensions

resize(height: int, width: int) → None

Resize the virtual pad and change internal variables to reflect that

Parameters

• height (int) – New virtual height

• width (int) – New virtual width

scroll_down(rate: int = 1) → bool

Scroll pad downwards

Note

Scroll limit must be set by child class

Parameters

rate (int) – Number of lines to scroll by

Returns

Indication of whether a limit was reached. False indicates a limit was reached and the pane cannot be scrolled further in that direction

Return type

bool

scroll_left(rate: int = 1) → bool

Scroll pad left

Note

Scroll limit must be set by child class

Parameters

rate (int) – Number of lines to scroll by

Returns

Indication of whether a limit was reached. False indicates a limit was reached and the pane cannot be scrolled further in that direction

Return type

bool

property scroll_limit_x: int

Limit the scroll on the x axis

property scroll_limit_y: int

Limit the scroll on the y axis

scroll_right(rate: int = 1) → bool

Scroll pad right

Note

Scroll limit must be set by child class

Parameters

rate (int) – Number of lines to scroll by

Returns

Indication of whether a limit was reached. False indicates a limit was reached and the pane cannot be scrolled further in that direction

Return type

bool

scroll_up(rate: int = 1) → bool

Scroll pad upwards

Note

Scroll limit must be set by child class

Parameters

rate (int) – Number of lines to scroll by

Returns

Indication of whether a limit was reached. False indicates a limit was reached and the pane cannot be scrolled further in that direction

Return type

bool

class canopen_monitor.ui.PopupWindow(parent: any, header: str = 'Alert', content: [str] = [], footer: str = 'ESC: close', style: any = None)

__draw__footer() → None

Add the footer to the window

__draw_content()

Read each line of the content and add to the window

__draw_header() → None

Add the header line to the window

_abc_impl = <_abc_data object>

apply_line_to_content_array(content, i, line, mid)

Apply the line break to the content array

break_lines(max_width: int, content: [str]) → [str]

determine_to_break_content(content, i, length, line, max_width, mid)

draw() → None

Abstract draw method, must be overwritten in child class draw should first resize the pad using: super().resize(w, h) then add content using: self._pad.addstr() then refresh using: super().refresh()

abstract method will clear and handle border

child class should also set _scroll_limit_x and _scroll_limit_y here

setUIDimension(p_height, p_width)

Set UI Dimension (x,y) by giving parent height and width

setWindowProperties(header, content, footer)

Set default window properties

toggle() → bool

class canopen_monitor.ui.SelectionPopup(parent: any, header: str = 'Alert', footer: str = 'ESC: close', style: Optional[any] = None)

Input form creates a popup window for selecting from a list of options

Parameters

• parent – parent ui element

• header – header text of popup window

• footer – footer text of popup window

• style – style of window

Type

any

Type

str

Type

str

Type

any

__draw__footer() → None

Add the footer to the window

__draw_content() → None

Read each line of the content and add to the window

__draw_header() → None

Add the header line to the window

_abc_impl = <_abc_data object>

draw() → None

Abstract draw method, must be overwritten in child class draw should first resize the pad using: super().resize(w, h) then add content using: self._pad.addstr() then refresh using: super().refresh()

abstract method will clear and handle border

child class should also set _scroll_limit_x and _scroll_limit_y here

get_value()

read_input(keyboard_input: int) → None

Read process keyboard input (ascii or backspace)

Parameters

keyboard_input – curses input character value from curses.getch

Type

int

toggle() → bool

Toggle window and reset selected item :return: value indicating whether the window is enabled :type: bool