Fix cursor hiding on input #18445
Fix cursor hiding on input #18445
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| @@ -143,7 +147,7 @@ class IslandWindow : | |||
| bool _minimizeToNotificationArea{ false }; | |||
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| std::unordered_map<UINT, SystemMenuItemInfo> _systemMenuItems; | |||
| UINT _systemMenuNextItemId; | |||
| UINT _systemMenuNextItemId = 0; | |||
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| void IslandWindow::ShowCursorMaybe(const UINT message) noexcept | ||
| { | ||
| if (_cursorHidden && (message == WM_ACTIVATE || message == WM_POINTERUPDATE)) |
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do you need one for losing focus or "switching to other window"?
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should we hide the cursor only when we are active? (so that somebody sending us a WM_KEYDOWN remotely doesn't hide the cursor?)
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My assumption was that WM_ACTIVATE is a superset of WM_SETFOCUS. Is that not the case? (Not sure how to test that because I always focus a window by activating it…)
I think that hiding the cursor on an external/emulated WM_KEYDOWN is fine since the sender must've had a reason to send WM_KEYDOWN specifically and I think it should behave like any other keyboard input.
| @@ -417,6 +417,16 @@ void WindowEmperor::HandleCommandlineArgs(int nCmdShow) | |||
| _dispatchSpecialKey(msg); | |||
| continue; | |||
| } | |||
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| if (msg.message == WM_KEYDOWN) | |||
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Oh I missed this comment. I think it should not be done on SYSKEYDOWN since that's for Alt-key combinations, which also doesn't hide the cursor in classic applications.
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The CoreWindow approach to implementing this has proven itself to be bug prone. This PR switches to using the much better Win32 ShowCursor API, which uses a reference count. This prevents the exact sort of race condition we have where we we disable the cursor in our code and the WinUI code then sets it to a different cursor internally which gets the system out of sync. There's no WinUI API to just hide the cursor and if it did, it would probably be a Boolean which would result in the same issue.
Closes #18400
Validation Steps Performed
It's difficult to assert the correctness of this approach, outside of just trying it out (which I did and it works). The good news is that this uses a static bool to ensure we only hide it exactly once and show it exactly once and we do the latter on every WM_ACTIVATE message which should hopefully restore the cursor when tabbing out and back in at least.