fix: WebView2 ACCESS_VIOLATION on rapid dispose/create cycles #325
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Root cause: Event handlers and callbacks not properly cleaned up before WebView2 controller destruction. Changes: - webview.h: Add ClearCallbacks() public method and UnregisterEventHandlers() - webview.cc: Unregister event handlers and clear callbacks before Close() - webview_bridge.cc: Control destruction order explicitly - webview.dart: Add setMuted() method for pre-dispose cleanup Tested: 100+ stress test cycles without crash Known issues (minor, deferred): - graphics_context.cc: COM object leak (once per launch) - webview_bridge.cc: Defensive callback clearing (not causing issues)
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Summary
Problem
When a WebView is disposed and a new one is created immediately after, an ACCESS_VIOLATION can occur. This happens because:
thispointer are not cleared before destructionChanges
ClearCallbacks()public method andUnregisterEventHandlers()private methodUnregisterEventHandlers()andClearCallbacks()beforeClose()in destructorsetMuted()method for pre-dispose cleanupTesting
Tested with 100+ rapid dispose/create cycles without crash (previously crashed within 2-3 cycles).
Known Issues (minor, deferred)
graphics_context.cc: Minor COM object leak (once per app launch) - added TODO commentwebview_bridge.cc: Defensive callback clearing suggestion - added TODO comment🤖 Generated with Claude Code