The functions below are used to create panels of buttons, menus, and field editors.
It is often convenient to encapsulate GUI elements and their state variables in a class. This allows multiple independent instances to be created. For example:
from neuron import h, gui
class MyWindow:
def __init__(self):
self.mystate = 0
self.myval = 3.14
self.checkbox = 1
h.xpanel('demo')
h.xradiobutton('Click me', (self.clicked, 0), 1)
h.xradiobutton('or me', (self.clicked, 1), 0)
h.xstatebutton('press me', (self, 'mystate'), self.statepressed)
h.xcheckbox('I am a checkbox', (self, 'checkbox'), self.checkboxpressed)
h.xvalue('Type a number', (self, 'myval'), 1, self.numberset)
h.xpanel()
def clicked(self, choice):
print('you switched the radio button! choice = %g' % choice)
def statepressed(self):
print('you pressed the state button. Value = %g' % self.mystate)
def checkboxpressed(self):
print('you clicked the checkbox. state = %g' % self.checkbox)
def numberset(self):
print('you set the number to: %g' % self.myval)
window = MyWindow()
Note
Top-level variables can be accessed through this_module where that is defined via import sys; this_module = sys.modules[__name__]; see examples below.
.. function:: xpanel
Syntax:
.. code-block::
python
h.xpanel('name')
h.xpanel('name', [0-1])
h.xpanel()
h.xpanel(x, y)
h.xpanel(scroll)
h.xpanel(scroll, x, y)
Description:
``h.xpanel("name")``
``h.xpanel("name", [0-1])``
Title of a new panel. Every
button, menu, and value between this and a closing ``xpanel()`` command
with no arguments (or placement args) belongs to this panel.
If the form is used with a second argument equal to 1, then
the panel is laid out horizontally. Otherwise the default is vertically.
``h.xpanel()``
``h.xpanel(x, y)``
done constructing the panel. so map it to the screen with position
optionally specified.
``h.xpanel(scroll)``
``h.xpanel(scroll, x, y)``
as above but if the first arg is a number, then the value determines
whether the panel will be inside a scrollbox. Scroll = 0 means a scrollbox
will NOT be used. Scroll = 1 means the panel will be inside a scrollbox.
Scroll = -1 is the default value and whether or not a scrollbox is used
is determined by the number of panel items in comparison with the
value of the panel_scroll property in the nrn.defaults file.
.. function:: xbutton
Syntax:
``h.xbutton('prompt', py_callable)``
``h.xbutton('prompt', (py_callable, arg))``
``h.xbutton('prompt', (py_callable, (arg1, arg2, ...))``
Description:
Adds a button to the currently open :func:`xpanel`. The label on the
button is *prompt*, and when the button is clicked, it calls the
*py_callable*. If instead of just ``py_callable`` a tuple containing
``py_callable`` and either an arg or tuple of args is passed, then
those are passed to the function when the button is clicked; this can
be used to allow one function to handle mutliple buttons, or buttons
created in unknown situations.
Example:
.. code-block::
python
from neuron import h, gui
def on_press():
print('You pressed the button.')
h.xpanel('Button demo')
h.xbutton('Press me', on_press)
h.xpanel()
.. image:: ../../images/xbutton.png
:align: center
Example:
.. code-block::
python
from neuron import h, gui
def on_press(button_id):
print('You clicked button: %d' % button_id)
def on_press3(a, b):
print('Button args: %s, %s' % (a, b))
h.xpanel('Button demo 2')
h.xbutton('Button 1', (on_press, 1))
h.xbutton('Button 2', (on_press, 2))
h.xbutton('Button 3', (on_press3, ('arg1', 'arg2')))
h.xpanel()
.. image:: ../../images/xbutton2.png
:align: center
.. function:: xstatebutton
Syntax:
.. code-block::
python
h.xstatebutton('prompt', (obj_or_module, 'varname') [, action_fn])
Description:
like :func:`xbutton`, but when pressed var is set to 0 or 1 so that it matches the
telltale state of the button. If the var is set by another way the
telltale state is updated to reflect the correct value.
Example:
.. code-block::
python
from neuron import h, gui
import sys; this_module = sys.modules[__name__]
button_state = 0
def on_press():
print('You pressed the button. The state is now: %g' % button_state)
h.xpanel('StateButton demo')
h.xstatebutton('Press me', (this_module, 'button_state'), on_press)
h.xpanel()
.. image:: ../../images/xstatebutton.png
:align: center
.. function:: xcheckbox
Syntax:
.. code-block::
python
h.xcheckbox('prompt', (obj_or_module, 'varname') [, action_fn])
Description:
like :func:`xstatebutton`, but checkbox appearance.
.. function:: xradiobutton
Syntax:
.. code-block::
python
h.xradiobutton('name', action_fn [, 0 or 1])
Description:
Like an :func:`xbutton` but highlights the most recently selected
button of a contiguous group (like a car radio, mutually exclusive
selection).
If the third argument is 1, then the button will be selected when the
panel is mapped onto the screen. However, in
this case the action should also be explicitly executed by the programmer.
That is not done automatically since it is often the case that the action
is invalid when the radio button is created. As with ``h.xbutton``, ``action_fn`` may
be a Python function handle, a tuple containing a function handle and an argument, or
a tuple containing a function handle and a tuple of arguments.
Example:
.. code-block::
python
from neuron import h, gui
def a(n):
"""function to be called when a radio button is toggled"""
print(n)
h.xpanel('panel')
h.xmenu('menu')
for i in range(1, 11):
h.xradiobutton('item %d' % i, (a, i))
h.xmenu()
h.xpanel()
.. image:: ../../images/xradiobutton.png
:align: center
.. function:: xmenu
Syntax:
.. code-block::
python
h.xmenu('title')
h.xmenu()
h.xmenu('title', 1)
h.xmenu(title, py_callable)
h.xmenu(title, py_callable, 1)
Description:
``h.xmenu("title")``
create a button in the panel with label "title" which, when
pressed, pops up a menu containing buttons and other menus. Every
:func:`xbutton` and :func:`xmenu` command between this and the closing ``xmenu()``
command with no arguments becomes the menu.
Don't put values into menus.
``h.xmenu()``
done defining the menu. Menus can be nested as in
.. code-block::
python
from neuron import h, gui
def selected1():
print('you selected option 1')
def selected2():
print('you selected option 2')
h.xpanel('xmenu demo')
h.xmenu('one')
h.xmenu('two')
h.xbutton('option 1', selected1)
h.xbutton('option 2', selected2)
h.xmenu()
h.xmenu()
h.xpanel()
.. image:: ../../images/xmenu1.png
:align: center
``h.xmenu("title", 1)``
adds the menu to the menubar. Note that a top level menu with no
second argument starts a new menubar. Normally these menubars have only
one top level item.
.. code-block::
python
from neuron import h, gui
import sys
def item_selected(n):
print('selected value %g' % n)
h.xpanel("menubar")
h.xmenu("first")
h.xbutton("one", (item_selected, 1))
h.xbutton("two", (item_selected, 2))
h.xbutton("Exit", sys.exit)
h.xmenu()
h.xmenu("second", 1)
h.xbutton("three", (item_selected, 3))
h.xbutton("four", (item_selected, 4))
h.xmenu("submenu")
h.xbutton("PI", (item_selected, h.PI))
h.xmenu()
h.xmenu()
h.xmenu("third", 1)
h.xbutton("five", (item_selected, 5))
h.xbutton("six", (item_selected, 6))
h.xmenu()
h.xmenu("nextline")
h.xbutton("seven", (item_selected, 7))
h.xbutton("eight", (item_selected, 8))
h.xmenu()
h.xpanel()
.. image:: ../../images/xmenu2.png
:align: center
``h.xmenu("title", py_callable)`` and ``h.xmenu("title", py_callable, 1)``
Dynamic menu added as item in panel or menu or (when third argument
is 1) to a menubar. An example of the first type is the
NEURONMainMenu/File/RecentDir and an example of the last type is the
NEURONMainMenu/Window
When the menu title button is selected, the stmt is executed in a context
like:
.. code-block::
python
h.xmenu("title")
py_callable()
h.xmenu()
which should normally build a menu list and then this list is mapped to
the screen as a normal walking menu.
.. code-block::
python
from neuron import h, gui
def select(i):
print('you selected %d' % i)
def make():
make.n += 1
for i in range(1, make.n + 1):
h.xbutton('label %d' % i, (select, i))
make.n = 0
h.xpanel("test")
h.xmenu("dynamic", make)
xpanel()
.. warning::
The dynamic menu syntax is currently unsupported in Python, but
the equivalent (passing a HOC command string) works in HOC.
.. function:: xlabel
Syntax:
.. code-block::
python
h.xlabel('string')
Description:
Show the string as a fixed label.
.. function:: xvarlabel
Syntax:
.. code-block::
python
h.xvarlabel(strref)
Description:
Show the string as its current value.
Example:
.. code-block::
python
from neuron import h, gui
mystr = h.ref('')
h.xpanel('xvarlabel demo')
h.xlabel('Dynamic text will appear below:')
h.xvarlabel(mystr)
h.xpanel()
# change the text displayed by changing mystr
mystr[0] = 'Hello world!'
.. image:: ../../images/xvarlabel.png
:align: center
.. warning::
Python strings are immutable. Thus the text displayed will only automatically
change if a strref is used, as in the example.
.. function:: xvalue
Syntax:
.. code-block::
python
h.xvalue("prompt", (obj_or_module, "varname") [, boolean_deflt, "action" [, boolean_canrun]])
h.xvalue("prompt", ref_var, [, boolean_deflt, "action" [, boolean_canrun]])
h.xvalue("prompt", "variable", 2)
Description:
``h.xvalue("prompt", (obj_or_module, "varname") [, boolean_deflt, "action" [, boolean_canrun]])``
create field editor for variable with the button labeled with "*prompt*".
If *boolean_deflt* == True (or 1) then add a checkbox which is checked when the
value of the field editor is different that when the editor was
created. Execute "action" when user enters a new value. If
*boolean_canrun* == True (or 1) then use a default_button widget kit appearance
instead of a push_button widget kit appearance.
``h.xvalue("prompt", (obj_or_module, "varname"), 2)``
a field editor that keeps getting updated every 10th :func:`doNotify`.
.. The domain of values that can be entered by the user into a field editor
.. may be limited to the domain specified by the
.. :func:`variable_domain` function , the domain specified for the variable in
.. a model description file, or a default domain that exists
.. for some special NEURON variables such as diam, Ra, L, etc.
.. For a field editor to check the domain, domain limits must be in effect
.. prior to creation of the field editor.
Example:
.. code-block::
python
from neuron import h, gui
import sys; this_module = sys.modules[__name__]
val = 42
h.xpanel('demo')
h.xvalue('enter value', (this_module, 'val'))
h.xpanel()
# changing val in the dialog will change val as seen by the program
.. image:: ../../images/xvalue.png
:align: center
.. seealso::
The example at the top of the file, which uses ``xvalue`` in an object.
.. function:: xpvalue
Syntax:
.. code-block::
python
h.xpvalue('prompt', ref, ...)
Description:
like :func:`xvalue` but uses a reference to the variable.
Example:
.. code-block::
python
from neuron import h, gui
val = h.ref(42)
def show_val():
print('value is: %g' % val[0])
h.xpanel('demo')
h.xpvalue('enter value', val, 1)
h.xbutton('show value', show_val)
h.xpanel()
.. image:: ../../images/xpvalue.png
:align: center
.. seealso::
:func:`units`
.. function:: xfixedvalue
Syntax:
.. code-block::
python
h.xfixedvalue("prompt", (obj_or_module, "varname"), boolean_deflt, boolean_usepointer)
Description:
like :func:`xvalue` but cannot be changed by the user except under
program control and there can be no action associated with it.
.. warning::
This is not implemented. For now, try to do the same thing
with :func:`xvarlabel`.
.. function:: xslider
Syntax:
.. code-block::
python
h.xslider((obj_or_module, "varname"), [low, high], [on_slide], [vert], [slow])
h.xslider(ref_var, [low, high], [on_slide], [vert], [slow])
Description:
Slider which is attached to the variable var. Whenever the slider
is moved, the optional *on_slide* is executed. The default range is
0 to 100. Steppers increase or decrease the value by 1/10 of the range.
Resolution is .01 of the range. vert=True (or 1) makes a vertical slider and
if there is no *on_slide* may be the 4th arg. slow=True (or 1) removes the "repeat
key" functionality from the slider(and arrow steppers) and also
prevents recursive calls to the *on_slide*. This is necessary if
a slider action is longer than the timeout delay. Otherwise the
slider can get in a state that appears to be an infinite loop.
The downside of slow=1 is that the var may not get the last value
of the slider if one releases the button during an action.
Examples:
.. code-block::
python
from neuron import h, gui
import sys; this_module = sys.modules[__name__]
val = 42
val_str = h.ref('Slider value: ')
def show_val():
val_str[0] = 'Slider value: %g' % val
h.xpanel('demo')
h.xvarlabel(val_str)
h.xslider((this_module, 'val'), 0, 100, show_val)
h.xpanel()
show_val()
.. image:: ../../images/xslider.png
:align: center
It is slightly more efficient to use an ``h.ref`` instead of a tuple.
The above example is functionally equivalent to:
.. code-block::
python
from neuron import h, gui
val = h.ref(42)
val_str = h.ref('Slider value: ')
def show_val():
val_str[0] = 'Slider value: %g' % val[0]
h.xpanel('demo')
h.xvarlabel(val_str)
h.xslider(val, 0, 100, show_val)
h.xpanel()
show_val()
You can also combine xslider with xvalue to report and modify its value (below example):
.. code-block::
python
from neuron import h, gui
class ValuePanel:
def __init__(self, init_val=42, label='',lower_limit=0,upper_limit=100):
self._val = h.ref(init_val)
h.xpanel('demo')
h.xlabel(label)
h.xvalue('enter value', self._val, True, self._bounds_check)
self.__lower_limit = lower_limit
self.__upper_limit = upper_limit
h.xslider(self._val, self.__lower_limit, self.__upper_limit)
h.xpanel()
def _bounds_check(self):
self.val = self.val
@property
def val(self):
return self._val[0]
@val.setter
def val(self, new_val):
new_val = max(self.__lower_limit, new_val)
self._val[0] = min(new_val, self.__upper_limit)
if __name__=="__main__":
hbox=h.HBox() # Horizontal box
hbox.intercept(True)
length=ValuePanel(label='length.val')
diam=ValuePanel(init_val=2,label='diam.val',lower_limit=0, upper_limit=5)
hbox.intercept(False)
hbox.map()
print('can read/change length.val, diam.val')
.. image:: ../../images/value_panel.png
:align: center
.. function:: units
Syntax:
.. code-block::
python
on or off = h.units(1 or 0)
current_units = h.units("varname" [, "units string"])
Description:
When units are on (default on) value editor buttons display the units
string (if it exists) along with the normal prompt string. Units for
L, diam, Ra, t, etc are built-in and units for membrane mechanism variables
are declared in the model description file. See modlunit .
Note that units are NOT saved in a session. Therefore, any user defined
variables must be given units before retrieving a session that shows them
in a panel.
The units display may be turned off with \ ``h.units(0)`` or by setting the
\ ``*units_on_flag: off`` in the nrn/lib/nrn.defaults file.
If the first arg is a string, it is treated as the name of the variable.
This is restricted to hoc variable names of the style, "name", or "classname.name".
Apart from the circumstance that the string arg style must be used when
executed from Python, a benefit is that it can be used when an instance
does not exist (no pointer to a variable of that type).
If there are no units specified for the variable name, or the variable
name is not defined, the return value is the empty string.
Examples:
.. code-block::
python
print(h.units('dt')) # ms
print(h.units('gna_hh')) # S/cm2
print(h.units('Ra')) # ohm-cm
print(h.units('L')) # um
print(h.units('ExpSyn.g')) # uS
.. warning::
When passing a string to ``h.units``, note that the string must be the
name of a HOC variable. Unfortunately, there is currently no way to declare
the units of a Python variable.