class MainWindow(object):
'''Represent initscr (the whole screen), and break it into a border,
header, and central region. Map F# keystrokes to Actions
'''
def __init__(self, initscr, screen_list, theme=None, force_bw=False):
'''Set the theme, and call reset to initialize the terminal to
prepare for the first screen.
'''
if theme is not None:
self.theme = theme
else:
self.theme = ColorTheme(force_bw=force_bw)
self.screen_list = screen_list
self.initscr = initscr
self.default_cursor_pos = (initscr.getmaxyx()[0] - 1, 0)
self.cursor_pos = self.default_cursor_pos
self.footer = None
self.header = None
self._cur_header_text = None
self.central_area = None
self.popup_win = None
self.error_line = None
self._active_win = None
self.continue_action = None
self.back_action = None
self.help_action = None
self.quit_action = None
self.actions = None
self.reset()
def redrawwin(self):
'''Completely repaint the screen'''
self.header.redrawwin()
self.footer.redrawwin()
self.error_line.redrawwin()
self.central_area.redrawwin()
if self._active_win is self.popup_win:
self.popup_win.redrawwin()
def do_update(self):
'''Wrapper to curses.doupdate()'''
curses.setsyx(*self.get_cursor_loc())
curses.doupdate()
def get_cursor_loc(self):
'''Retrieve the current cursor position from the active UI
element.
'''
cursor = self.central_area.get_cursor_loc()
if cursor is None:
cursor = self.cursor_pos
return cursor
def reset(self):
'''Create the InnerWindows representing the header, footer/border,
error line, and main central_area
'''
window_size = self.initscr.getmaxyx()
win_size_y = window_size[0]
win_size_x = window_size[1]
footer_area = WindowArea(1, win_size_x, win_size_y - 1, 0)
self.footer = InnerWindow(footer_area,
color_theme=self.theme,
color=self.theme.border)
top = self.initscr.derwin(1, win_size_x, 0, 0)
left = self.initscr.derwin(win_size_y - 2, 1, 1, 0)
right = self.initscr.derwin(win_size_y - 2, 1, 1, win_size_x - 1)
self.footer.more_windows = [top, left, right]
self.footer.set_color(self.theme.border)
header_area = WindowArea(1, win_size_x - 2, 1, 1)
self.header = InnerWindow(header_area,
color_theme=self.theme,
color=self.theme.header)
central_win_area = WindowArea(win_size_y - 4, win_size_x - 2, 2, 1)
self.central_area = InnerWindow(central_win_area,
border_size=(0, 2),
color_theme=self.theme)
self._active_win = self.central_area
popup_win_area = WindowArea(central_win_area.lines - 10,
central_win_area.columns - 20, 5, 10,
central_win_area.lines - 10)
self.popup_win = ScrollWindow(popup_win_area,
window=self.central_area,
color=self.theme.error_msg,
highlight_color=self.theme.error_msg)
error_area = WindowArea(1, win_size_x - 2, win_size_y - 2, 1)
self.error_line = ErrorWindow(error_area, color_theme=self.theme)
self.reset_actions()
def reset_actions(self):
'''Reset the actions to the defaults, clearing any custom actions
registered by individual screens
'''
self.continue_action = Action(curses.KEY_F2, _("Continue"),
self.screen_list.get_next)
self.back_action = Action(curses.KEY_F3, _("Back"),
self.screen_list.previous_screen)
self.help_action = Action(curses.KEY_F6, _("Help"),
self.screen_list.show_help)
self.quit_action = Action(curses.KEY_F9, _("Quit"),
self.screen_list.quit)
self.set_default_actions()
def clear(self):
'''Clear all InnerWindows and reset_actions()'''
self.header.clear()
self.footer.clear()
self.central_area.clear()
self.error_line.clear_err()
self.reset_actions()
def set_header_text(self, header_text):
'''Set the header_text'''
text = center_columns(header_text, self.header.area.columns - 1)
self.header.add_text(text)
self._cur_header_text = text
def set_default_actions(self):
'''Clear the actions dictionary and add the default actions back
into it
'''
self.actions = {}
self.actions[self.continue_action.key] = self.continue_action
self.actions[self.back_action.key] = self.back_action
self.actions[self.help_action.key] = self.help_action
self.actions[self.quit_action.key] = self.quit_action
def show_actions(self):
'''Read through the actions dictionary, displaying all the actions
descriptive text along the footer (along with a prefix linked to
its associated keystroke)
'''
self.footer.window.clear()
if InnerWindow.USE_ESC:
prefix = " Esc-"
else:
prefix = " F"
strings = []
length = 0
action_format = "%s%i_%s"
for key in sorted(self.actions.keys()):
key_num = key - curses.KEY_F0
action_text = self.actions[key].text
action_str = action_format % (prefix, key_num, action_text)
strings.append(action_str)
display_str = "".join(strings)
max_len = self.footer.window.getmaxyx()[1]
length = textwidth(display_str)
if not InnerWindow.USE_ESC:
length += (len(" Esc-") - len(" F")) * len(self.actions)
if length > max_len:
raise ValueError("Can't display footer actions - string too long")
self.footer.window.addstr(display_str.encode(get_encoding()))
self.footer.window.noutrefresh()
def getch(self):
'''Call down into central_area to get a keystroke, and, if necessary,
update the footer to switch to using the Esc- prefixes
'''
input_key = self._active_win.getch()
if input_key == InnerWindow.REPAINT_KEY:
self.redrawwin()
input_key = None
if InnerWindow.UPDATE_FOOTER:
InnerWindow.UPDATE_FOOTER = False
self.show_actions()
return input_key
def process_input(self, current_screen):
'''Read input until a keystroke that fires a screen change
is caught
'''
input_key = None
while input_key not in self.actions:
input_key = self.getch()
input_key = self.central_area.process(input_key)
self.do_update()
return self.actions[input_key].do_action(current_screen)
def pop_up(self,
header,
question,
left_btn_txt,
right_btn_txt,
color=None):
'''Suspend the current screen, setting the header
to 'header', presenting the 'question,' and providing two 'buttons'.
Returns True if the RIGHT button is selected, False if the LEFT is
selected. The LEFT button is initially selected.
'''
# Hide the cursor, storing its previous state (visibility) so
# it can be restored when finished. Then, move the cursor
# to the default position (in case this terminal type does not support
# hiding the cursor entirely)
try:
old_cursor_state = curses.curs_set(0)
except curses.error:
old_cursor_state = 2
cursor_loc = curses.getsyx()
curses.setsyx(self.cursor_pos[0], self.cursor_pos[1])
# Add the header, a border, and the question to the window
self.popup_win.window.border()
header_x = (self.popup_win.area.columns - textwidth(header)) / 2
self.popup_win.add_text(header, 0, header_x)
y_loc = 2
y_loc += self.popup_win.add_paragraph(question, y_loc, 2)
y_loc += 2
# Set the background color based on the parameter given, or choose
# a default based on the theme. Set the highlight_color by flipping
# the A_REVERSE bit of the color
if color is None:
color = self.popup_win.color
self.popup_win.set_color(color)
highlight_color = color ^ curses.A_REVERSE
# Create two "buttons" of equal size by finding the larger of the
# two, and centering them
max_len = max(textwidth(left_btn_txt), textwidth(right_btn_txt))
left_btn_txt = " [ %s ]" % left_btn_txt.center(max_len)
right_btn_txt = " [ %s ]" % right_btn_txt.center(max_len)
button_len = textwidth(left_btn_txt) + 1
win_size = self.popup_win.window.getmaxyx()
left_area = WindowArea(1, button_len, y_loc,
(win_size[1] / 2) - (button_len + 2))
left_button = ListItem(left_area,
window=self.popup_win,
text=left_btn_txt,
color=color,
highlight_color=highlight_color)
right_area = WindowArea(1, button_len, y_loc, win_size[1] / 2 + 2)
right_button = ListItem(right_area,
window=self.popup_win,
text=right_btn_txt,
color=color,
highlight_color=highlight_color)
# Highlight the left button, clear any errors on the screen,
# and display the pop up
self.popup_win.activate_object(left_button)
self.popup_win.no_ut_refresh()
self.error_line.clear_err()
self.do_update()
self._active_win = self.popup_win
# Loop until the user selects an option.
input_key = None
while input_key != curses.KEY_ENTER:
input_key = self.getch()
input_key = self.popup_win.process(input_key)
if input_key == curses.KEY_LEFT:
self.popup_win.activate_object(left_button)
elif input_key == curses.KEY_RIGHT:
self.popup_win.activate_object(right_button)
self.do_update()
self._active_win = self.central_area
user_selected = (self.popup_win.get_active_object() is right_button)
# Clear the pop up and restore the previous screen, including the
# cursor position and visibility
self.popup_win.clear()
self.central_area.redrawwin()
curses.setsyx(cursor_loc[0], cursor_loc[1])
try:
curses.curs_set(old_cursor_state)
except curses.error:
pass
self.do_update()
return user_selected
