utility function create_event_handler with more options, like preventDefault/stopPropagation

Author: mhochsteger

webgpu/input_handler.py

@@ -1,9 +1,6 @@
 import threading
 from typing import Callable
 
-from .platform import is_pyodide
-from .utils import to_js
-
 
 class InputHandler:
     _js_handlers: dict
@@ -96,11 +93,14 @@ def wrapper(event):
         return wrapper
 
     def register_callbacks(self):
-        from .platform import create_proxy
+        from .platform import create_event_handler
 
-        options = to_js({"capture": True})
         for event in ["mousedown", "mouseup", "mousemove", "wheel", "mouseout"]:
-            js_handler = create_proxy(self._handle_js_event(event), ignore_return_value=True)
+            js_handler = create_event_handler(
+                self._handle_js_event(event),
+                prevent_default=True,
+                stop_propagation=event not in ["mousemove", "mouseout"],
+            )
             self.html_canvas["on" + event] = js_handler
             self._js_handlers[event] = js_handler
 

webgpu/link/link.js

@@ -153,6 +153,7 @@ class CrossLink {
       this.connection.onOpen(() => {
         this.expose('importPackage', window.importPackage);
         this.expose('addStyleFile', window.addStyleFile);
+        this.expose('createEventHandler', window.createEventHandler);
         console.log('connection open');
         resolve();
       });
@@ -596,3 +597,19 @@ window.patchedRequestAnimationFrame = (device, context, target) => {
     device.queue.submit([encoder.finish()]);
   });
 };
+
+window.createEventHandler = (callback, options = {}) => {
+  return (ev) => {
+    if (options.preventDefault) {
+      ev.preventDefault();
+    }
+    if (options.stopPropagation) {
+      ev.stopPropagation();
+    }
+    if (options.stopImmediatePropagation) {
+      ev.stopImmediatePropagation();
+    }
+    callback(ev);
+    return options.returnValue;
+  };
+};

webgpu/platform.py

@@ -18,8 +18,20 @@
 link = None
 
 
-def create_event_handler(func, prevent_default=True):
-    pass
+def create_event_handler(
+    func,
+    prevent_default=True,
+    stop_propagation=False,
+    stop_immediate_propagation=False,
+    return_value=None,
+):
+    options = {
+        "preventDefault": prevent_default,
+        "stopPropagation": stop_propagation,
+        "stopImmediatePropagation": stop_immediate_propagation,
+        "returnValue": return_value,
+    }
+    return js.createEventHandler(func, options)
 
 
 try:
@@ -97,6 +109,7 @@ class JsPromise:
 
 if is_pyodide:
     import json
+
     import js as pyodide_js
 
     from .link.base import LinkBase