data-menu: show add data list for empty viewers (spacetelescope#3272)

* show list of data to add for empty viewer rather than opening data menu
* improved menu hints to find load data button
* clear viewer icon when viewer is deleted ensures that callbacks to icons being updated will be retriggered when/if viewer recreated

CHANGES.rst

@@ -4,7 +4,7 @@
 New Features
 ------------
 
-* New design for viewer legend. [#3220, #3254, #3263, #3264]
+* New design for viewer legend. [#3220, #3254, #3263, #3264, #3272]
 
 Cubeviz
 ^^^^^^^

jdaviz/app.py

@@ -154,7 +154,7 @@ def to_unit(self, data, cid, values, original_units, target_units):
                      'plugin-color-picker': 'components/plugin_color_picker.vue',
                      'plugin-input-header': 'components/plugin_input_header.vue',
                      'glue-state-sync-wrapper': 'components/glue_state_sync_wrapper.vue',
-                     'data-menu-add-data': 'components/data_menu_add_data.vue',
+                     'data-menu-add': 'components/data_menu_add.vue',
                      'data-menu-remove': 'components/data_menu_remove.vue',
                      'data-menu-subset-edit': 'components/data_menu_subset_edit.vue'}
 
@@ -2134,6 +2134,10 @@ def remove(stack_items):
         if cid in self._viewer_store:
             del self._viewer_store[cid]
 
+        # clear from the viewer icons dictionary
+        if cid in self.state.viewer_icons:
+            del self.state.viewer_icons[cid]
+
         self.hub.broadcast(ViewerRemovedMessage(cid, sender=self))
 
     def vue_data_item_unload(self, event):

jdaviz/components/data_menu_add_data.vue → jdaviz/components/data_menu_add.vue

@@ -12,10 +12,11 @@
       >
         <v-btn
           icon
+          :class="loaded_n_data > 0 ? 'invert-if-dark' : 'invert-if-dark pulse'"
           v-bind="attrs"
           v-on="on"
         >
-          <v-icon class="invert-if-dark">mdi-plus</v-icon>
+          <v-icon>mdi-plus</v-icon>
         </v-btn>
       </j-tooltip>
     </template>
@@ -61,6 +62,6 @@
 
 <script>
 module.exports = {
-  props: ['dataset_items', 'subset_tools'],
+  props: ['dataset_items', 'subset_tools', 'loaded_n_data'],
 };
 </script>

jdaviz/components/viewer_data_select.vue

@@ -137,7 +137,7 @@ module.exports = {
     return {
       // default to passed values, whenever value or uncertainty are changed
       // updateTruncatedValues will overwrite the displayed values
-      data_menu_open: this.$props.viewer.open_data_menu_if_empty && Object.keys(this.$props.viewer.selected_data_items).length == 0 && this.$props.data_items.length > 0,
+      data_menu_open: false,
       multi_select: multi_select,
       showExtraItems: Object.keys(this.$props.viewer.selected_data_items).length == 0,
       valueTrunc: this.value,

jdaviz/configs/default/plugins/data_menu/data_menu.py

@@ -67,6 +67,7 @@ class DataMenu(TemplateMixin, LayerSelectMixin, DatasetSelectMixin):
 
     dm_layer_selected = List().tag(sync=True)
 
+    loaded_n_data = Integer(0).tag(sync=True)
     selected_n_layers = Integer(0).tag(sync=True)
     selected_n_data = Integer(0).tag(sync=True)
     selected_n_subsets = Integer(0).tag(sync=True)
@@ -135,12 +136,6 @@ def user_api(self):
     def existing_subset_labels(self):
         return [sg.label for sg in self.app.data_collection.subset_groups]
 
-    @observe('layer_items')
-    def _update_data_not_in_viewer(self, msg):
-        # changing the layers in the viewer needs to trigger an update to dataset_items
-        # through the set filters
-        self.dataset._on_data_changed()
-
     def _set_viewer_id(self):
         # viewer_ids are not populated on the viewer at init, so we'll keep checking and set
         # these the first time that they are available
@@ -180,7 +175,7 @@ def _dm_layer_selected_changed(self, event={}):
             # not possible from UI interaction, but instead caused by a selected
             # layer being removed (deleting a selected subset, etc).  We want
             # to update dm_layer_selected in order to preserve layer.selected
-            self._update_dm_layer_selected(event)
+            self._layers_changed(event)
             return
         with self.during_select_sync():
             # map index in dm_layer_selected (inverse order of layer_items)
@@ -190,7 +185,7 @@ def _dm_layer_selected_changed(self, event={}):
                                    for i in self.dm_layer_selected]
 
     @observe('layer_selected', 'layer_items')
-    def _update_dm_layer_selected(self, event={}):
+    def _layers_changed(self, event={}):
         if not hasattr(self, 'layer') or not self.layer.multiselect:  # pragma: no cover
             return
         if not self._during_select_sync:
@@ -200,13 +195,18 @@ def _update_dm_layer_selected(self, event={}):
                 self.dm_layer_selected = [layer_labels.index(label) for label in self.layer.selected
                                           if label in layer_labels]
 
+        subset_labels = self.existing_subset_labels
+
         if event.get('name') == 'layer_items':
-            # don't need to make the updates below unless the selection has been changed
+            # changing the layers in the viewer needs to trigger an update to dataset_items
+            # through the set filters
+            self.dataset._on_data_changed()
+            self.loaded_n_data = len([lyr for lyr in self.layer.choices
+                                      if lyr not in subset_labels])
             return
 
         # update internal counts and tooltips
         self.selected_n_layers = len(self.layer.selected)
-        subset_labels = self.existing_subset_labels
         self.selected_n_subsets = len([lyr for lyr in self.layer.selected if lyr in subset_labels])
         self.selected_n_data = self.selected_n_layers - self.selected_n_subsets
 
@@ -229,7 +229,7 @@ def _update_dm_layer_selected(self, event={}):
                 # with an update
                 self.info_enabled = False
                 self.info_tooltip = ''
-            if self.layer_items[self.dm_layer_selected[0]].get('from_plugin', False):
+            elif self.layer_items[self.dm_layer_selected[0]].get('from_plugin', False):
                 self.info_enabled = False
                 self.info_tooltip = 'Selected data layer is a plugin product and does not have metadata'  # noqa
             else: