Update view/controller observables

src/aiidalab_qe/app/configuration/hubbard.py

@@ -1,7 +1,5 @@
 import ipywidgets as ipw
-import traitlets as tl
 
-from aiida import orm
 from aiida_quantumespresso.data.hubbard_structure import HubbardStructureData
 
 from .model import ConfigurationModel
@@ -10,14 +8,6 @@
 class HubbardSettings(ipw.VBox):
     """Widget for setting up Hubbard parameters."""
 
-    input_structure = tl.Union(
-        [
-            tl.Instance(orm.StructureData),
-            tl.Instance(orm.KpointsData),
-        ],
-        allow_none=True,
-    )
-
     def __init__(self, model: ConfigurationModel, **kwargs):
         from aiidalab_qe.common.widgets import LoadingWidget
 
@@ -27,6 +17,10 @@ def __init__(self, model: ConfigurationModel, **kwargs):
         )
 
         self._model = model
+        self._model.observe(
+            self._on_input_structure_change,
+            "input_structure",
+        )
 
         self.links = []
         self.eigenvalues_widget_links = []
@@ -78,6 +72,7 @@ def render(self):
 
         self.hubbard_widget = ipw.VBox()
         self.eigenvalues_widget = ipw.VBox()
+
         self.container = ipw.VBox()
 
         self.children = [
@@ -90,19 +85,15 @@ def render(self):
             self.container,
         ]
 
-        ipw.dlink(
-            (self._model, "input_structure"),
-            (self, "input_structure"),
-        )
-
         self.rendered = True
 
+        self._build_hubbard_widget()
+
     def reset(self):
         """Reset the widget."""
         self._unsubscribe()
         self._model.advanced.hubbard.reset()
 
-    @tl.observe("input_structure")
     def _on_input_structure_change(self, change):
         self._unsubscribe()
         self._model.advanced.hubbard.update()
@@ -124,6 +115,8 @@ def _build_hubbard_widget(self):
             hubbard_widget (ipywidgets.VBox):
                 The widget containing the input fields for defining Hubbard U values.
         """
+        if not self.rendered:
+            return
 
         children = []
 

src/aiidalab_qe/app/configuration/magnetization.py

@@ -1,7 +1,4 @@
 import ipywidgets as ipw
-import traitlets as tl
-
-from aiida import orm
 
 from .model import ConfigurationModel
 
@@ -20,16 +17,6 @@ class MagnetizationSettings(ipw.VBox):
         input_structure(StructureData): trait that contains the input_structure (confirmed structure from previous step)
     """
 
-    input_structure = tl.Union(
-        [
-            tl.Instance(orm.StructureData),
-            tl.Instance(orm.KpointsData),
-        ],
-        allow_none=True,
-    )
-    electronic_type = tl.Unicode()
-    magnetization_type = tl.Unicode()
-
     def __init__(self, model: ConfigurationModel, **kwargs):
         from aiidalab_qe.common.widgets import LoadingWidget
 
@@ -40,8 +27,20 @@ def __init__(self, model: ConfigurationModel, **kwargs):
         )
 
         self._model = model
+        self._model.observe(
+            self._on_input_structure_change,
+            "input_structure",
+        )
+        self._model.workchain.observe(
+            self._on_electronic_type_change,
+            "electronic_type",
+        )
+        self._model.advanced.magnetization.observe(
+            self._on_magnetization_type_change,
+            "type",
+        )
 
-        self.kind_widget_links = []
+        self.links = []
 
         self.rendered = False
 
@@ -96,48 +95,36 @@ def render(self):
 
         self.children = [self.description]
 
-        with self.hold_trait_notifications():
-            ipw.dlink(
-                (self._model, "input_structure"),
-                (self, "input_structure"),
-            )
-            ipw.dlink(
-                (self._model.workchain, "electronic_type"),
-                (self, "electronic_type"),
-            )
-            ipw.dlink(
-                (self._model.advanced.magnetization, "type"),
-                (self, "magnetization_type"),
-            )
-
         self.rendered = True
 
+        self._build_kinds_widget()
+
     def reset(self):
         self._model.advanced.magnetization.reset()
 
-    @tl.observe("input_structure")
-    def _on_input_structure_change(self, change):
+    def _on_input_structure_change(self, _):
         self._model.advanced.magnetization.update()
-        self._build_kinds_widget(change)
+        self._build_kinds_widget()
 
-    @tl.observe("electronic_type")
     def _on_electronic_type_change(self, change):
         self._switch_widgets(change)
 
-    @tl.observe("magnetization_type")
     def _on_magnetization_type_change(self, change):
         self._toggle_widgets(change)
 
-    def _build_kinds_widget(self, change):
+    def _build_kinds_widget(self):
+        if not self.rendered:
+            return
+
         children = []
 
-        if (input_structure := change["new"]) is None:
+        if self._model.input_structure is None:
             labels = []
-            for link in self.kind_widget_links:
+            for link in self.links:
                 link.unlink()
-            self.kind_widget_links.clear()
+            self.links.clear()
         else:
-            labels = input_structure.get_kind_names()
+            labels = self._model.input_structure.get_kind_names()
 
         for label in labels:
             kind_widget = ipw.BoundedFloatText(
@@ -158,7 +145,7 @@ def _build_kinds_widget(self, change):
                     },
                 ],
             )
-            self.kind_widget_links.append(link)
+            self.links.append(link)
             ipw.dlink(
                 (self._model.advanced, "override"),
                 (kind_widget, "disabled"),

src/aiidalab_qe/app/main.py

@@ -35,18 +35,15 @@ def __init__(self, qe_auto_setup=True):
             model=struct_model,
             auto_advance=True,
         )
-
         self.configure_step = ConfigureQeAppWorkChainStep(
             model=config_model,
             auto_advance=True,
         )
-
         self.submit_step = SubmitQeAppWorkChainStep(
             model=submit_model,
             auto_advance=True,
             qe_auto_setup=qe_auto_setup,
         )
-
         self.results_step = ViewQeAppWorkChainStatusAndResultsStep(model=results_model)
 
         # Link the models of the application steps
@@ -105,7 +102,7 @@ def __init__(self, qe_auto_setup=True):
         )
 
         ipw.dlink(
-            (self.submit_step, "process"),
+            (submit_model, "process"),
             (self.work_chain_selector, "value"),
             transform=lambda node: None if node is None else node.pk,
         )

src/aiidalab_qe/app/result/__init__.py

@@ -22,8 +22,6 @@
 
 
 class ViewQeAppWorkChainStatusAndResultsStep(ipw.VBox, WizardAppWidgetStep):
-    process = tl.Unicode(allow_none=True)
-
     def __init__(self, model: ResultsModel, **kwargs):
         from aiidalab_qe.common.widgets import LoadingWidget
 
@@ -107,11 +105,6 @@ def render(self):
             "process",
         )
 
-        ipw.dlink(
-            (self._model, "process"),
-            (self, "process"),
-        )
-
         self.rendered = True
 
     def can_reset(self):
@@ -129,14 +122,14 @@ def _on_process_change(self, _):
         self._update_kill_button_layout()
 
     def _on_click_kill_button(self, _=None):
-        workchain = [orm.load_node(self.process)]
+        workchain = [orm.load_node(self._model.process)]
         control.kill_processes(workchain)
         self._update_kill_button_layout()
 
     def _update_kill_button_layout(self):
         if (
-            self.process is None
-            or self.process == ""
+            self._model.process is None
+            or self._model.process == ""
             or self.state
             in (
                 self.State.SUCCESS,
@@ -145,17 +138,17 @@ def _update_kill_button_layout(self):
         ):
             self.kill_button.layout.display = "none"
         else:
-            process = orm.load_node(self.process)
+            process = orm.load_node(self._model.process)
             if process.is_finished or process.is_excepted:
                 self.kill_button.layout.display = "none"
             else:
                 self.kill_button.layout.display = "block"
 
     def _update_state(self):
-        if self.process is None:
+        if self._model.process is None:
             self.state = self.State.INIT
         else:
-            process = orm.load_node(self.process)
+            process = orm.load_node(self._model.process)
             process_state = process.process_state
             if process_state in (
                 ProcessState.CREATED,

src/aiidalab_qe/app/structure/__init__.py

@@ -6,7 +6,6 @@
 import pathlib
 
 import ipywidgets as ipw
-import traitlets as tl
 
 from aiida import orm
 from aiida_quantumespresso.data.hubbard_structure import HubbardStructureData
@@ -48,8 +47,6 @@ class StructureSelectionStep(ipw.VBox, WizardAppWidgetStep):
     structure importers and the structure editors can be extended by plugins.
     """
 
-    structure = tl.Instance(orm.StructureData, allow_none=True)
-
     def __init__(self, model: StructureModel, **kwargs):
         from aiidalab_qe.common.widgets import LoadingWidget
 
@@ -63,6 +60,10 @@ def __init__(self, model: StructureModel, **kwargs):
             self._on_confirmation_change,
             "confirmed",
         )
+        self._model.observe(
+            self._on_structure_change,
+            "structure",
+        )
 
         self.rendered = False
 
@@ -135,13 +136,12 @@ def render(self):
             lambda state: state != self.State.CONFIGURED,
         )
         self.confirm_button.on_click(self.confirm)
+
         self.message_area = ipw.HTML()
 
-        # Create directional link from the (read-only) 'structure_node' traitlet of the
-        # structure manager to our 'structure' traitlet:
         ipw.dlink(
             (self.manager, "structure_node"),
-            (self, "structure"),
+            (self._model, "structure"),
         )
 
         self.children = [
@@ -163,23 +163,18 @@ def render(self):
             self.confirm_button,
         ]
 
-        ipw.dlink(
-            (self._model, "structure"),
-            (self, "structure"),
-        )
-
         self.rendered = True
 
     def set_structure(self, structure):
         self._model.structure = structure
 
     def is_saved(self):
         """Check if the current structure is confirmed."""
-        return self.structure == self._model.confirmed_structure
+        return self._model.structure == self._model.confirmed_structure
 
     def confirm(self, _=None):
         self.manager.store_structure()
-        self._model.confirmed_structure = self.structure
+        self._model.confirmed_structure = self._model.structure
         self._model.confirmed = True
         self.message_area.value = ""
 
@@ -194,7 +189,6 @@ def reset(self):
             self.manager.viewer.structure = None
             self.manager.output.value = ""
 
-    @tl.observe("structure")
     def _on_structure_change(self, _):
         self._model.reset()
         self._update_widget_text()
@@ -204,17 +198,17 @@ def _on_confirmation_change(self, _):
         self._update_state()
 
     def _update_widget_text(self):
-        if self.structure is None:
+        if self._model.structure is None:
             self.structure_name_text.value = ""
             self.message_area.value = ""
         else:
             self.manager.output.value = ""
-            self.structure_name_text.value = str(self.structure.get_formula())
+            self.structure_name_text.value = str(self._model.structure.get_formula())
 
     def _update_state(self):
         if self._model.confirmed:
             self.state = self.State.SUCCESS
-        elif self.structure is None:
+        elif self._model.structure is None:
             self.state = self.State.READY
         else:
             self.state = self.State.CONFIGURED