.. _panel: GUI Widgets ----------- 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: .. code-block:: python 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', lambda: self.clicked(0), 1) h.xradiobutton('or me', lambda: 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() .. image:: ../../images/guiwidgets-example.png :align: center .. note:: Top-level variables can be accessed using the ``__main__`` module. ---- .. 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: .. code-block:: python h.xbutton('prompt', py_callable) 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*. 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 ---- .. 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 __main__ button_state = 0 def on_press(): print 'You pressed the button. The state is now:', button_state h.xpanel('StateButton demo') h.xstatebutton('Press me', (__main__, '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. Example: .. code-block:: python from neuron import h, gui def a(n): """function to be called when a radio button is toggled""" print n def call_a(n): """returns a function that calls a with the specified parameter""" return lambda: a(n) h.xpanel('panel') h.xmenu('menu') for i in xrange(1, 11): h.xradiobutton('item %d' % i, call_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 def item_selected(n): print 'selected value %g' % n h.xpanel("menubar") h.xmenu("first") h.xbutton("one", lambda: item_selected(1)) h.xbutton("two", lambda: item_selected(2)) h.xmenu() h.xmenu("second", 1) h.xbutton("three", lambda: item_selected(3)) h.xbutton("four", lambda: item_selected(4)) h.xmenu("submenu") h.xbutton("PI", lambda: item_selected(h.PI)) h.xmenu() h.xmenu() h.xmenu("third", 1) h.xbutton("five", lambda: item_selected(5)) h.xbutton("six", lambda: item_selected(6)) h.xmenu() h.xmenu("nextline") h.xbutton("seven", lambda: item_selected(7)) h.xbutton("eight", lambda: 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', i def call_select(i): """returns a function that always calls select(i)""" return lambda: select(i) n = 0 def make(): global n n += 1 for i in xrange(1, n + 1): h.xbutton('label %d' % i, call_select(i)) 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('strref 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", "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* == 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* == 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 __main__ val = 42 h.xpanel('demo') h.xvalue('enter value', (__main__, '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:', 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=1 makes a vertical slider and if there is no *on_slide* may be the 4th arg. slow=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 __main__ val = 42 val_str = h.ref('Slider value: ') def show_val(): global val_str val_str[0] = 'Slider value: %g' % val h.xpanel('demo') h.xvarlabel(val_str) h.xslider((__main__, '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(): global val_str 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() ---- .. 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.