Merge pull request #924 from gaphor/custom-item-and-handle-finder

Custom item and handle finder

Author: amolenaar

gaphas/handlemove.py

@@ -3,7 +3,7 @@
 import logging
 from functools import singledispatch
 from operator import itemgetter
-from typing import TYPE_CHECKING, Iterable, Sequence
+from typing import TYPE_CHECKING, Iterable, Sequence, Iterator
 
 from gaphas.connector import ConnectionSink, ConnectionSinkType, Connector
 from gaphas.handle import Handle
@@ -163,7 +163,7 @@ def item_at_point(
     pos: Pos,
     distance: float = 0.5,
     exclude: Sequence[Item] = (),
-) -> Iterable[Item]:
+) -> Iterator[Item]:
     """Return the topmost item located at ``pos`` (x, y).
 
     Parameters:

gaphas/tool/hover.py

@@ -1,18 +1,28 @@
 from gi.repository import Gdk, Gtk
 
-from gaphas.cursor import cursor
-from gaphas.tool.itemtool import find_item_and_handle_at_point
-
+from typing import Callable, Union
 
-def hover_tool() -> Gtk.EventController:
+from gaphas.cursor import cursor
+from gaphas.tool.itemtool import default_find_item_and_handle_at_point
+from gaphas.connector import Handle
+from gaphas.item import Item
+from gaphas.types import Pos
+from gaphas.view import GtkView
+
+
+def hover_tool(
+    find_item_and_handle_at_point: Callable[
+        [GtkView, Pos], Union[tuple[Item, Union[Handle, None]], tuple[None, None]]
+    ] = default_find_item_and_handle_at_point,
+) -> Gtk.EventController:
     """Highlight the currently hovered item."""
     ctrl = Gtk.EventControllerMotion.new()
-    ctrl.connect("motion", on_motion)
+    ctrl.connect("motion", on_motion, find_item_and_handle_at_point)
     ctrl.cursor_name = ""
     return ctrl
 
 
-def on_motion(ctrl, x, y):
+def on_motion(ctrl, x, y, find_item_and_handle_at_point):
     view = ctrl.get_widget()
     pos = (x, y)
     item, handle = find_item_and_handle_at_point(view, pos)

gaphas/tool/itemtool.py

@@ -1,6 +1,7 @@
 from __future__ import annotations
 
 import logging
+from typing import Callable, Union
 
 from gi.repository import Gdk, Gtk
 
@@ -17,11 +18,24 @@
 log = logging.getLogger(__name__)
 
 
-def item_tool() -> Gtk.GestureDrag:
+def default_find_item_and_handle_at_point(
+    view: GtkView, pos: Pos
+) -> Union[tuple[Item, Union[Handle, None]], tuple[None, None]]:
+    item, handle = handle_at_point(view, pos)
+    return item or next(item_at_point(view, pos), None), handle  # type: ignore[return-value]
+
+
+def item_tool(
+    find_item_and_handle_at_point: Callable[
+        [GtkView, Pos], tuple[Item, Handle | None] | tuple[None, None]
+    ] = default_find_item_and_handle_at_point,
+) -> Gtk.GestureDrag:
     """Handle item movement and movement of handles."""
     gesture = Gtk.GestureDrag.new()
     drag_state = DragState()
-    gesture.connect("drag-begin", on_drag_begin, drag_state)
+    gesture.connect(
+        "drag-begin", on_drag_begin, drag_state, find_item_and_handle_at_point
+    )
     gesture.connect("drag-update", on_drag_update, drag_state)
     gesture.connect("drag-end", on_drag_end, drag_state)
     return gesture
@@ -44,7 +58,7 @@ def moving(self):
             yield self.moving_handle
 
 
-def on_drag_begin(gesture, start_x, start_y, drag_state):
+def on_drag_begin(gesture, start_x, start_y, drag_state, find_item_and_handle_at_point):
     view = gesture.get_widget()
     pos = (start_x, start_y)
     selection = view.selection
@@ -90,13 +104,6 @@ def on_drag_begin(gesture, start_x, start_y, drag_state):
         moving.start_move((start_x, start_y))
 
 
-def find_item_and_handle_at_point(
-    view: GtkView, pos: Pos
-) -> tuple[Item | None, Handle | None]:
-    item, handle = handle_at_point(view, pos)
-    return item or next(item_at_point(view, pos), None), handle  # type: ignore[call-overload]
-
-
 def moving_items(view):
     """Filter the items that should eventually be moved.