from contextlib import nullcontext

from .backend_cairo import FigureCanvasCairo

from .backend_gtk4 import GLib, Gtk, FigureCanvasGTK4, _BackendGTK4

class FigureCanvasGTK4Cairo(FigureCanvasCairo, FigureCanvasGTK4):

def _set_device_pixel_ratio(self, ratio):

# Cairo in GTK4 always uses logical pixels, so we don't need to do anything for

# changes to the device pixel ratio.

return False

def on_draw_event(self, widget, ctx):

if self._idle_draw_id:

GLib.source_remove(self._idle_draw_id)

self._idle_draw_id = 0

self.draw()

with (self.toolbar._wait_cursor_for_draw_cm() if self.toolbar

else nullcontext()):

self._renderer.set_context(ctx)

allocation = self.get_allocation()

Gtk.render_background(

self.get_style_context(), ctx,

allocation.x, allocation.y,

allocation.width, allocation.height)

self.figure.draw(self._renderer)

@_BackendGTK4.export

class _BackendGTK4Cairo(_BackendGTK4):

FigureCanvas = FigureCanvasGTK4Cairo