"""A call-tip window class for Tkinter/IDLE.
After tooltip.py, which uses ideas gleaned from PySol.
Used by calltip.py.
"""
from tkinter import Label, LEFT, SOLID, TclError
from idlelib.tooltip import TooltipBase
HIDE_EVENT = "<<calltipwindow-hide>>"
HIDE_SEQUENCES = ("<Key-Escape>", "<FocusOut>")
CHECKHIDE_EVENT = "<<calltipwindow-checkhide>>"
CHECKHIDE_SEQUENCES = ("<KeyRelease>", "<ButtonRelease>")
CHECKHIDE_TIME = 100 # milliseconds
MARK_RIGHT = "calltipwindowregion_right"
class CalltipWindow(TooltipBase):
"""A call-tip widget for tkinter text widgets."""
def __init__(self, text_widget):
"""Create a call-tip; shown by showtip().
text_widget: a Text widget with code for which call-tips are desired
"""
# Note: The Text widget will be accessible as self.anchor_widget
super(CalltipWindow, self).__init__(text_widget)
self.label = self.text = None
self.parenline = self.parencol = self.lastline = None
self.hideid = self.checkhideid = None
self.checkhide_after_id = None
def get_position(self):
"""Choose the position of the call-tip."""
curline = int(self.anchor_widget.index("insert").split('.')[0])
if curline == self.parenline:
anchor_index = (self.parenline, self.parencol)
else:
anchor_index = (curline, 0)
box = self.anchor_widget.bbox("%d.%d" % anchor_index)
if not box:
box = list(self.anchor_widget.bbox("insert"))
# align to left of window
box[0] = 0
box[2] = 0
return box[0] + 2, box[1] + box[3]
def position_window(self):
"Reposition the window if needed."
curline = int(self.anchor_widget.index("insert").split('.')[0])
if curline == self.lastline:
return
self.lastline = curline
self.anchor_widget.see("insert")
super(CalltipWindow, self).position_window()
def showtip(self, text, parenleft, parenright):
"""Show the call-tip, bind events which will close it and reposition it.
text: the text to display in the call-tip
parenleft: index of the opening parenthesis in the text widget
parenright: index of the closing parenthesis in the text widget,
or the end of the line if there is no closing parenthesis
"""
# Only called in calltip.Calltip, where lines are truncated
self.text = text
if self.tipwindow or not self.text:
return
self.anchor_widget.mark_set(MARK_RIGHT, parenright)
self.parenline, self.parencol = map(
int, self.anchor_widget.index(parenleft).split("."))
super(CalltipWindow, self).showtip()
self._bind_events()
def showcontents(self):
"""Create the call-tip widget."""
self.label = Label(self.tipwindow, text=self.text, justify=LEFT,
background="#ffffd0", foreground="black",
relief=SOLID, borderwidth=1,
font=self.anchor_widget['font'])
self.label.pack()
def checkhide_event(self, event=None):
"""Handle CHECK_HIDE_EVENT: call hidetip or reschedule."""
if not self.tipwindow:
# If the event was triggered by the same event that unbound
# this function, the function will be called nevertheless,
# so do nothing in this case.
return None
# Hide the call-tip if the insertion cursor moves outside of the
# parenthesis.
curline, curcol = map(int, self.anchor_widget.index("insert").split('.'))
if curline < self.parenline or \
(curline == self.parenline and curcol <= self.parencol) or \
self.anchor_widget.compare("insert", ">", MARK_RIGHT):
self.hidetip()
return "break"
# Not hiding the call-tip.
self.position_window()
# Re-schedule this function to be called again in a short while.
if self.checkhide_after_id is not None:
self.anchor_widget.after_cancel(self.checkhide_after_id)
self.checkhide_after_id = \
self.anchor_widget.after(CHECKHIDE_TIME, self.checkhide_event)
return None
def hide_event(self, event):
"""Handle HIDE_EVENT by calling hidetip."""
if not self.tipwindow:
# See the explanation in checkhide_event.
return None
self.hidetip()
return "break"
def hidetip(self):
"""Hide the call-tip."""
if not self.tipwindow:
return
try:
self.label.destroy()
except TclError:
pass
self.label = None
self.parenline = self.parencol = self.lastline = None
try:
self.anchor_widget.mark_unset(MARK_RIGHT)
except TclError:
pass
try:
self._unbind_events()
except (TclError, ValueError):
# ValueError may be raised by MultiCall
pass
super(CalltipWindow, self).hidetip()
def _bind_events(self):
"""Bind event handlers."""
self.checkhideid = self.anchor_widget.bind(CHECKHIDE_EVENT,
self.checkhide_event)
for seq in CHECKHIDE_SEQUENCES:
self.anchor_widget.event_add(CHECKHIDE_EVENT, seq)
self.anchor_widget.after(CHECKHIDE_TIME, self.checkhide_event)
self.hideid = self.anchor_widget.bind(HIDE_EVENT,
self.hide_event)
for seq in HIDE_SEQUENCES:
self.anchor_widget.event_add(HIDE_EVENT, seq)
def _unbind_events(self):
"""Unbind event handlers."""
for seq in CHECKHIDE_SEQUENCES:
self.anchor_widget.event_delete(CHECKHIDE_EVENT, seq)
self.anchor_widget.unbind(CHECKHIDE_EVENT, self.checkhideid)
self.checkhideid = None
for seq in HIDE_SEQUENCES:
self.anchor_widget.event_delete(HIDE_EVENT, seq)
self.anchor_widget.unbind(HIDE_EVENT, self.hideid)
self.hideid = None
def _calltip_window(parent): # htest #
from tkinter import Toplevel, Text, LEFT, BOTH
top = Toplevel(parent)
top.title("Test call-tips")
x, y = map(int, parent.geometry().split('+')[1:])
top.geometry("250x100+%d+%d" % (x + 175, y + 150))
text = Text(top)
text.pack(side=LEFT, fill=BOTH, expand=1)
text.insert("insert", "string.split")
top.update()
calltip = CalltipWindow(text)
def calltip_show(event):
calltip.showtip("(s='Hello world')", "insert", "end")
def calltip_hide(event):
calltip.hidetip()
text.event_add("<<calltip-show>>", "(")
text.event_add("<<calltip-hide>>", ")")
text.bind("<<calltip-show>>", calltip_show)
text.bind("<<calltip-hide>>", calltip_hide)
text.focus_set()
if __name__ == '__main__':
from unittest import main
main('idlelib.idle_test.test_calltip_w', verbosity=2, exit=False)
from idlelib.idle_test.htest import run
run(_calltip_window)
