def add_scrollbars(outer, InnerType, *inner_args, **inner_kw):
""" Creates widget of type `InnerType` inside `outer` widget and adds
vertical and horizontal scroll bars for created widget.
"""
outer.rowconfigure(0, weight=1)
outer.rowconfigure(1, weight=0)
outer.columnconfigure(0, weight=1)
outer.columnconfigure(1, weight=0)
# container for inner frame, it supports scrolling
canvas = Canvas(outer, width=1, height=1)
canvas.grid(row=0, column=0, sticky="NESW")
inner = InnerType(canvas, *inner_args, **inner_kw)
inner_id = canvas.create_window((0, 0), window=inner, anchor="nw")
h_sb = Scrollbar(outer, orient="horizontal", command=canvas.xview)
h_sb._visible = False
v_sb = Scrollbar(outer, orient="vertical", command=canvas.yview)
v_sb._visible = False
canvas.configure(xscrollcommand=h_sb.set, yscrollcommand=v_sb.set)
def scrollbar_visibility():
"Automatically shows & hides the scroll bar."
cnv_w, cnv_h = canvas.winfo_width(), canvas.winfo_height()
inner_w, inner_h = inner.winfo_width(), inner.winfo_height()
if inner_w <= cnv_w:
if h_sb._visible:
h_sb.grid_forget()
h_sb._visible = False
else:
if not h_sb._visible:
h_sb.grid(row=1, column=0, sticky="NESW")
h_sb._visible = True
if inner_h <= cnv_h:
if v_sb._visible:
v_sb.grid_forget()
v_sb._visible = False
else:
if not v_sb._visible:
v_sb.grid(row=0, column=1, sticky="NESW")
v_sb._visible = True
def inner_configure(_):
scrollbar_visibility()
canvas.configure(
scrollregion=canvas.bbox(ALL),
# Require as many space as inner widget do.
width=inner.winfo_reqwidth(),
height=inner.winfo_reqheight())
inner.bind("<Configure>", inner_configure, "+")
def canvas_configure(e):
scrollbar_visibility()
# Get to the inner widget at least desired space.
# Stretch it when possible.
canvas.itemconfig(inner_id,
width=max(e.width, inner.winfo_reqwidth()),
height=max(e.height, inner.winfo_reqheight()))
canvas.bind("<Configure>", canvas_configure, "+")
return inner
def add_scrollbars(outer, InnerType, *inner_args, **kw):
""" Creates widget of type `InnerType` inside `outer` widget and adds
vertical and horizontal scroll bars for created widget.
:param kw:
those arguments are passed to `InnerType` constructor except for:
- row/column: `grid` coordinates inside `outer` (default: 0)
- wheel: support wheel scrolling when mouse is over inner widget
(default: False)
- inner_kw: see below
To pass same named arguments to `InnerType` wrap them into a `dict` and
pass it with name "inner_kw" in "kw".
"""
row, column = kw.pop("row", 0), kw.pop("column", 0)
wheel = kw.pop("wheel", False)
kw.update(kw.pop("inner_kw", {}))
outer.rowconfigure(row, weight=1)
outer.rowconfigure(row + 1, weight=0)
outer.columnconfigure(column, weight=1)
outer.columnconfigure(column + 1, weight=0)
# container for inner frame, it supports scrolling
canvas = Canvas(outer, width=1, height=1)
canvas.grid(row=row, column=row, sticky="NESW")
inner = InnerType(canvas, *inner_args, **kw)
inner_id = canvas.create_window((0, 0), window=inner, anchor="nw")
h_sb = Scrollbar(outer, orient="horizontal", command=canvas.xview)
h_sb._visible = False
v_sb = Scrollbar(outer, orient="vertical", command=canvas.yview)
v_sb._visible = False
canvas.configure(xscrollcommand=h_sb.set, yscrollcommand=v_sb.set)
def scrollbar_visibility():
"Automatically shows & hides the scroll bar."
cnv_w, cnv_h = canvas.winfo_width(), canvas.winfo_height()
inner_w, inner_h = inner.winfo_width(), inner.winfo_height()
if inner_w <= cnv_w:
if h_sb._visible:
h_sb.grid_forget()
h_sb._visible = False
else:
if not h_sb._visible:
h_sb.grid(row=row + 1, column=column, sticky="NESW")
h_sb._visible = True
if inner_h <= cnv_h:
if v_sb._visible:
v_sb.grid_forget()
v_sb._visible = False
else:
if not v_sb._visible:
v_sb.grid(row=row, column=column + 1, sticky="NESW")
v_sb._visible = True
def inner_configure(_):
scrollbar_visibility()
canvas.configure(
scrollregion=canvas.bbox(ALL),
# Require as many space as inner widget do.
width=inner.winfo_reqwidth(),
height=inner.winfo_reqheight())
inner.bind("<Configure>", inner_configure, "+")
def canvas_configure(e):
scrollbar_visibility()
# Get to the inner widget at least desired space.
# Stretch it when possible.
canvas.itemconfig(inner_id,
width=max(e.width, inner.winfo_reqwidth()),
height=max(e.height, inner.winfo_reqheight()))
canvas.bind("<Configure>", canvas_configure, "+")
if not wheel:
return inner
def on_wheel(e):
w = e.widget
# Is the `w`idget our inner?
m = w
while m is not None:
if m is inner:
break
m = m.master
else:
# Outer widget
return
cls = w.winfo_class()
if cls in WHEELED_WIDGETS:
# When mouse pointer is over `WHEELED_WIDGETS` the canvas
# must not be scrolled. But there are few exceptions for
# convenience.
try:
a, b = w.yview()
except:
# not all "wheeled" widgets provides `yview` and those values
# prevents heuristics about fully scrolled `w`idgets below.
a, b = None, None
if e.delta > 0:
if a == 0.0:
pass # w is fully scrolled up
elif w.winfo_rooty() < canvas.winfo_rooty():
pass # user does not see upper border of w
# XXX: we also have to prevent scrolling of `w` but
# returning "break" does not work.
else:
return
elif e.delta < 0:
if b == 1.0:
pass # w is fully scrolled down
elif (w.winfo_rooty() + w.winfo_height() >
canvas.winfo_rooty() + canvas.winfo_height()):
pass # user does not see bottom border of w
else:
return
else:
return
canvas.yview("scroll", -e.delta, "units")
bind_all_mouse_wheel(inner, on_wheel, "+")
return inner
