Show and hide parameters after cpanel init

helipad/ipy-styles.css

@@ -128,4 +128,5 @@
 	margin-right: 12px;
 }
 
-.helipad_cpanel > .p-Widget { margin-bottom: 0.5em; }
+.helipad_cpanel > .p-Widget { margin-bottom: 0.5em; }
+.helipad_accordion_hidden { display: none; } /* For some reason Ipywidgets throws 'Javascript Error: t is undefined' when accessing accordion layouts */

helipad/locales/helipad.pot

@@ -271,7 +271,11 @@ msgid "Cannot add checkgrids or per-item parameters to groups."
 msgstr ""
 
 #: param.py:399
-msgid "Cannot remove built-in parameters."
+msgid "Cannot hide or remove built-in parameters."
+msgstr ""
+
+#: param.py:418
+msgid "Cannot show parameter before control panel is launched."
 msgstr ""
 
 #: param.py:421

helipad/param.py

@@ -395,12 +395,36 @@ def remove(self, name: str):
 		if isinstance(name, (list, tuple)): return [self.remove(n) for n in name]
 
 		if name not in self: return False
-		if getattr(self[name], 'config', False): raise ValueError(ï('Cannot remove built-in parameters.'))
+		if getattr(self[name], 'config', False): raise ValueError(ï('Cannot hide or remove built-in parameters.'))
 		self._destroy(self[name])
 
 		del self[name]
 		return True
 
+	def hide(self, name: str):
+		if isinstance(name, (list, tuple)): return [self.remove(n) for n in name]
+		if name not in self or not self[name].element: return False
+		if getattr(self[name], 'config', False): raise ValueError(ï('Cannot hide or remove built-in parameters.'))
+
+		if isNotebook():
+			if getattr(self[name], 'per', True) or self[name].type=='checkgrid': self[name].element.add_class('helipad_accordion_hidden')
+			else: self[name].element.layout.display = 'none'
+		else:
+			if getattr(self[name], 'per', True) or self[name].type=='checkgrid': self[name].element.pack_forget()
+			else: self[name].element.master.pack_forget()
+
+	def show(self, name: str):
+		if not self.model.cpanel:
+			warnings.warn(ï('Cannot show parameter before control panel is launched.'), None, 2)
+			return False
+
+		if isNotebook():
+			if getattr(self[name], 'per', True) or self[name].type=='checkgrid': self[name].element.remove_class('helipad_accordion_hidden')
+			else: self[name].element.layout.display = None
+		else:
+			if getattr(self[name], 'per', True) or self[name].type=='checkgrid': self[name].element.pack(fill='x')
+			else: self[name].element.master.pack(fill='x')
+
 	def _destroy(self, item):
 		if item.element:
 			if isNotebook(): item.element.close()
@@ -469,7 +493,7 @@ def clear(self):
 		configs = {k:v for k,v in self.items() if getattr(v, 'config', False)}
 		super().clear()
 		self.update(configs)
-
+	
 	@property
 	def globals(self):
 		"""The subset of global parameters, i.e. those added with `per=None`. https://helipad.dev/functions/params/#globals"""

sample-models/Cities.py

@@ -14,14 +14,17 @@
 
 #Constrain the parameter space to values resulting in H* = 100
 def constrain(model, var, val):
-	if var=='city': model.params['rent'].disabled(val)
+	if var=='city':
+		if val: model.params.hide('rent')
+		else: model.params.show('rent')
+		#model.params['rent'].disabled(val)
 	elif model.param('city'):
 		if var=='fixed':
-			model.params['rent'].enable() #Tkinter won't let you update the value of a disabled widget...
+			model.params['rent'].enable() #Tkinter won't let you update the value of a disabled widget…
 			model.param('rent', .04+.037*val)
 			model.params['rent'].disable()
 		# if var=='rent':
-		# 	model.params['fixed'].enable() #Tkinter won't let you update the value of a disabled widget...
+		# 	model.params['fixed'].enable() #Tkinter won't let you update the value of a disabled widget…
 		# 	model.param('fixed', 24.7777*val-.9284659)
 		# 	model.params['fixed'].disable()
 
@@ -77,6 +80,10 @@ def expWage(self, H):
 # AGENT BEHAVIOR
 #================
 
+@heli.hook
+def CpanelPostInit(cpanel):
+	constrain(cpanel.model, 'city', True)
+
 #This is here to make sure that the agents param gets reset at the beginning of each run
 #Otherwise the parameter persists between runs
 @heli.hook