initial classes to help support creating layers for toggling visibility on the canvas for associated items

daemon/core/gui/graph/graph.py

@@ -25,6 +25,7 @@ from core.gui.graph.edges import (
     create_edge_token,
 )
 from core.gui.graph.enums import GraphMode, ScaleOption
+from core.gui.graph.layers import CanvasLayers
 from core.gui.graph.node import CanvasNode
 from core.gui.graph.shape import Shape
 from core.gui.graph.shapeutils import ShapeType, is_draw_shape, is_marker
@@ -62,6 +63,7 @@ class CanvasGraph(tk.Canvas):
         super().__init__(master, highlightthickness=0, background="#cccccc")
         self.app: "Application" = app
         self.core: "CoreClient" = core
+        self.layers = CanvasLayers(self)
         self.mode: GraphMode = GraphMode.SELECT
         self.annotation_type: Optional[ShapeType] = None
         self.selection: Dict[int, int] = {}

daemon/core/gui/graph/layers.py

@@ -0,0 +1,58 @@
+import tkinter as tk
+from typing import TYPE_CHECKING, Dict, Iterable, Set
+
+if TYPE_CHECKING:
+    from core.gui.graph.graph import CanvasGraph
+
+
+class CanvasLayers:
+    def __init__(self, canvas: "CanvasGraph"):
+        self.canvas: "CanvasGraph" = canvas
+        self.layers: Dict[str, Set[int]] = {}
+        self.hidden: Set[str] = set()
+
+    def names(self) -> Iterable[str]:
+        return self.layers.keys()
+
+    def add_layer(self, name: str) -> bool:
+        if name in self.layers:
+            return False
+        else:
+            self.layers[name] = set()
+            return True
+
+    def delete_layer(self, name: str) -> None:
+        items = self.layers.pop(name, set())
+        hidden_items = self.all_hidden()
+        items -= hidden_items
+        self.canvas.config(items, state=tk.NORMAL)
+
+    def add_item(self, name: str, item: int) -> None:
+        if name in self.layers:
+            self.layers[name].add(item)
+            if name in self.hidden:
+                self.canvas.config(item, state=tk.HIDDEN)
+
+    def delete_item(self, name: str, item: int) -> None:
+        if name in self.layers:
+            self.layers[name].remove(item)
+            hidden_items = self.all_hidden()
+            if item not in hidden_items:
+                self.canvas.config(item, state=tk.NORMAL)
+
+    def toggle_layer(self, name: str) -> None:
+        items = self.layers[name]
+        if name in self.hidden:
+            self.hidden.remove(name)
+            hidden_items = self.all_hidden()
+            items -= hidden_items
+            self.canvas.config(items, state=tk.NORMAL)
+        else:
+            self.hidden.add(name)
+            self.canvas.config(items, state=tk.HIDDEN)
+
+    def all_hidden(self) -> Set[int]:
+        items = set()
+        for name in self.hidden:
+            items |= self.layers[name]
+        return items