Para obtener la cadena en un Text
widget, simplemente se puede usar el get
método definido para el Text
cual acepta de 1 a 2 argumentos como start
y end
posiciones de caracteres text_widget_object.get(start, end=None)
,. Si solo start
se pasa y end
no se pasa, devuelve solo el carácter individual posicionado en start
, si también end
se pasa, devuelve todos los caracteres entre posiciones start
y end
como cadena.
También hay cadenas especiales, que son variables para el Tk subyacente. Uno de ellos sería "end"
o tk.END
que representa la posición variable del último carácter en el Text
widget. Un ejemplo sería devolver todo el texto en el widget, con text_widget_object.get('1.0', 'end')
o text_widget_object.get('1.0', 'end-1c')
si no desea el último carácter de nueva línea.
Manifestación
Vea la demostración a continuación que selecciona los caracteres entre las posiciones dadas con controles deslizantes:
try:
import tkinter as tk
except:
import Tkinter as tk
class Demo(tk.LabelFrame):
"""
A LabeFrame that in order to demonstrate the string returned by the
get method of Text widget, selects the characters in between the
given arguments that are set with Scales.
"""
def __init__(self, master, *args, **kwargs):
tk.LabelFrame.__init__(self, master, *args, **kwargs)
self.start_arg = ''
self.end_arg = None
self.position_frames = dict()
self._create_widgets()
self._layout()
self.update()
def _create_widgets(self):
self._is_two_args = tk.Checkbutton(self,
text="Use 2 positional arguments...")
self.position_frames['start'] = PositionFrame(self,
text="start='{}.{}'.format(line, column)")
self.position_frames['end'] = PositionFrame( self,
text="end='{}.{}'.format(line, column)")
self.text = TextWithStats(self, wrap='none')
self._widget_configs()
def _widget_configs(self):
self.text.update_callback = self.update
self._is_two_args.var = tk.BooleanVar(self, value=False)
self._is_two_args.config(variable=self._is_two_args.var,
onvalue=True, offvalue=False)
self._is_two_args['command'] = self._is_two_args_handle
for _key in self.position_frames:
self.position_frames[_key].line.slider['command'] = self.update
self.position_frames[_key].column.slider['command'] = self.update
def _layout(self):
self._is_two_args.grid(sticky='nsw', row=0, column=1)
self.position_frames['start'].grid(sticky='nsew', row=1, column=0)
#self.position_frames['end'].grid(sticky='nsew', row=1, column=1)
self.text.grid(sticky='nsew', row=2, column=0,
rowspan=2, columnspan=2)
_grid_size = self.grid_size()
for _col in range(_grid_size[0]):
self.grid_columnconfigure(_col, weight=1)
for _row in range(_grid_size[1] - 1):
self.grid_rowconfigure(_row + 1, weight=1)
def _is_two_args_handle(self):
self.update_arguments()
if self._is_two_args.var.get():
self.position_frames['end'].grid(sticky='nsew', row=1, column=1)
else:
self.position_frames['end'].grid_remove()
def update(self, event=None):
"""
Updates slider limits, argument values, labels representing the
get method call.
"""
self.update_sliders()
self.update_arguments()
def update_sliders(self):
"""
Updates slider limits based on what's written in the text and
which line is selected.
"""
self._update_line_sliders()
self._update_column_sliders()
def _update_line_sliders(self):
if self.text.lines_length:
for _key in self.position_frames:
self.position_frames[_key].line.slider['state'] = 'normal'
self.position_frames[_key].line.slider['from_'] = 1
_no_of_lines = self.text.line_count
self.position_frames[_key].line.slider['to'] = _no_of_lines
else:
for _key in self.position_frames:
self.position_frames[_key].line.slider['state'] = 'disabled'
def _update_column_sliders(self):
if self.text.lines_length:
for _key in self.position_frames:
self.position_frames[_key].column.slider['state'] = 'normal'
self.position_frames[_key].column.slider['from_'] = 0
_line_no = int(self.position_frames[_key].line.slider.get())-1
_max_line_len = self.text.lines_length[_line_no]
self.position_frames[_key].column.slider['to'] = _max_line_len
else:
for _key in self.position_frames:
self.position_frames[_key].column.slider['state'] = 'disabled'
def update_arguments(self):
"""
Updates the values representing the arguments passed to the get
method, based on whether or not the 2nd positional argument is
active and the slider positions.
"""
_start_line_no = self.position_frames['start'].line.slider.get()
_start_col_no = self.position_frames['start'].column.slider.get()
self.start_arg = "{}.{}".format(_start_line_no, _start_col_no)
if self._is_two_args.var.get():
_end_line_no = self.position_frames['end'].line.slider.get()
_end_col_no = self.position_frames['end'].column.slider.get()
self.end_arg = "{}.{}".format(_end_line_no, _end_col_no)
else:
self.end_arg = None
self._update_method_labels()
self._select()
def _update_method_labels(self):
if self.end_arg:
for _key in self.position_frames:
_string = "text.get('{}', '{}')".format(
self.start_arg, self.end_arg)
self.position_frames[_key].label['text'] = _string
else:
_string = "text.get('{}')".format(self.start_arg)
self.position_frames['start'].label['text'] = _string
def _select(self):
self.text.focus_set()
self.text.tag_remove('sel', '1.0', 'end')
self.text.tag_add('sel', self.start_arg, self.end_arg)
if self.end_arg:
self.text.mark_set('insert', self.end_arg)
else:
self.text.mark_set('insert', self.start_arg)
class TextWithStats(tk.Text):
"""
Text widget that stores stats of its content:
self.line_count: the total number of lines
self.lines_length: the total number of characters per line
self.update_callback: can be set as the reference to the callback
to be called with each update
"""
def __init__(self, master, update_callback=None, *args, **kwargs):
tk.Text.__init__(self, master, *args, **kwargs)
self._events = ('<KeyPress>',
'<KeyRelease>',
'<ButtonRelease-1>',
'<ButtonRelease-2>',
'<ButtonRelease-3>',
'<Delete>',
'<<Cut>>',
'<<Paste>>',
'<<Undo>>',
'<<Redo>>')
self.line_count = None
self.lines_length = list()
self.update_callback = update_callback
self.update_stats()
self.bind_events_on_widget_to_callback( self._events,
self,
self.update_stats)
@staticmethod
def bind_events_on_widget_to_callback(events, widget, callback):
"""
Bind events on widget to callback.
"""
for _event in events:
widget.bind(_event, callback)
def update_stats(self, event=None):
"""
Update self.line_count, self.lines_length stats and call
self.update_callback.
"""
_string = self.get('1.0', 'end-1c')
_string_lines = _string.splitlines()
self.line_count = len(_string_lines)
del self.lines_length[:]
for _line in _string_lines:
self.lines_length.append(len(_line))
if self.update_callback:
self.update_callback()
class PositionFrame(tk.LabelFrame):
"""
A LabelFrame that has two LabelFrames which has Scales.
"""
def __init__(self, master, *args, **kwargs):
tk.LabelFrame.__init__(self, master, *args, **kwargs)
self._create_widgets()
self._layout()
def _create_widgets(self):
self.line = SliderFrame(self, orient='vertical', text="line=")
self.column = SliderFrame(self, orient='horizontal', text="column=")
self.label = tk.Label(self, text="Label")
def _layout(self):
self.line.grid(sticky='ns', row=0, column=0, rowspan=2)
self.column.grid(sticky='ew', row=0, column=1, columnspan=2)
self.label.grid(sticky='nsew', row=1, column=1)
self.grid_rowconfigure(1, weight=1)
self.grid_columnconfigure(1, weight=1)
class SliderFrame(tk.LabelFrame):
"""
A LabelFrame that encapsulates a Scale.
"""
def __init__(self, master, orient, *args, **kwargs):
tk.LabelFrame.__init__(self, master, *args, **kwargs)
self.slider = tk.Scale(self, orient=orient)
self.slider.pack(fill='both', expand=True)
if __name__ == '__main__':
root = tk.Tk()
demo = Demo(root, text="text.get(start, end=None)")
with open(__file__) as f:
demo.text.insert('1.0', f.read())
demo.text.update_stats()
demo.pack(fill='both', expand=True)
root.mainloop()
"end-1c"
oEND+"1c"
, de lo contrario, obtendrá la nueva línea adicional que el widget de texto siempre agrega.