Added lazy-loader for complex views

sbapp/ui/layouts.py

@@ -9,7 +9,6 @@ MDNavigationLayout:
     ScreenManager:
         id: screen_manager
         transition: SlideTransition()
-        # transition: NoTransition()
 
         MDScreen:
             name: "starting_screen"
@@ -241,6 +240,39 @@ MDScreen:
                 font_size: "32dp"
 """
 
+layout_loader_screen = """
+MDScreen:
+    name: "loader_screen"
+    
+    BoxLayout:
+        orientation: "vertical"
+
+        MDTopAppBar:
+            title: ""
+            anchor_title: "left"
+            elevation: 0
+            left_action_items:
+                [['menu', None ]]
+            right_action_items:
+                [
+                ]
+
+        AnchorLayout:
+            padding: [dp(0), dp(72), dp(0), dp(0)]
+            anchor_x: "center"
+            anchor_y: "center"
+
+            BoxLayout:
+                spacing: dp(36)
+                orientation: 'vertical'
+                size_hint_y: None
+
+                MDIconButton:
+                    pos_hint: {"center_x": .5, "center_y": .5}
+                    icon: "dots-horizontal"
+                    icon_size: "64dp"
+"""
+
 layout_connectivity_screen = """
 MDScreen:
     name: "connectivity_screen"

sbapp/ui/telemetry.py

@@ -366,13 +366,32 @@ class Telemetry():
         self.sensors_screen.ids.telemetry_s_information_text.text = str(self.app.sideband.config["telemetry_s_information_text"])
         self.sensors_screen.ids.telemetry_s_information_text.bind(focus=self.sensors_save)
 
-    def sensors_action(self, sender=None):
-        self.sensors_init()
-        self.app.root.ids.screen_manager.transition.direction = "left"
+    def sensors_open(self, sender=None, direction="left", no_transition=False):
+        if no_transition:
+            self.app.root.ids.screen_manager.transition = self.app.no_transition
+        else:
+            self.app.root.ids.screen_manager.transition = self.app.slide_transition
+            self.app.root.ids.screen_manager.transition.direction = direction
+
         self.app.root.ids.screen_manager.current = "sensors_screen"
         self.app.root.ids.nav_drawer.set_state("closed")
         self.app.sideband.setstate("app.displaying", self.app.root.ids.screen_manager.current)
 
+        if no_transition:
+            self.app.root.ids.screen_manager.transition = self.app.slide_transition
+
+    def sensors_action(self, sender=None):
+        if self.app.root.ids.screen_manager.has_screen("sensors_screen"):
+            self.sensors_open()
+        else:
+            self.app.loader_action()
+            def final(dt):
+                self.sensors_init()
+                def o(dt):
+                    self.sensors_open(no_transition=True)
+                Clock.schedule_once(o, 0.45)
+            Clock.schedule_once(final, 0.275)
+
     def telemetry_location_toggle(self, sender=None, event=None):
         if sender == self.sensors_screen.ids.telemetry_s_location:
             if self.sensors_screen.ids.telemetry_s_location.active: