Stylus.SetIsPressAndHoldEnabled does not work when Switch.System.Windows.Input.Stylus.EnablePointerSupport is enabled

[aquinn39]

• .NET Core Version: 6.0.1
• Windows version: 22000.376 (Though this seems to occur on all versions of Windows that Switch.System.Windows.Input.Stylus.EnablePointerSupport is supported on)
• Does the bug reproduce also in WPF for .NET Framework 4.8?: Yes
• Is this bug related specifically to tooling in Visual Studio (e.g. XAML Designer, Code editing, etc...)? No

Problem description:

Actual behavior:
Tapping and holding on a control with Stylus.IsPressAndHoldEnabled disabled while the app has Switch.System.Windows.Input.Stylus.EnablePointerSupport enabled simply results in the same behaviour as if Stylus.IsPressAndHoldEnabled was enabled (pressing and holding results in a right click rather than a normal click, also if the control is something like a button, its state does not indicate that it is currently in the pressed state). Basically, Stylus.IsPressAndHoldEnabled has no effect when Switch.System.Windows.Input.Stylus.EnablePointerSupport is on.

Expected behavior:
Stylus.IsPressAndHoldEnabled being set to false on a control should have the same effect as it does when Switch.System.Windows.Input.Stylus.EnablePointerSupport is disabled.

Minimal repro:
Create a new WPF app, call AppContext.SetSwitch("Switch.System.Windows.Input.Stylus.EnablePointerSupport", "True") in the application startup event. Then, set Stylus.IsPressAndHoldEnabled to disabled on any control, such as a button (e.g. Stylus.SetIsPressAndHoldEnabled(Button1, False)). Stylus.IsPressAndHoldEnabled will have no effect on the control.

[lindexi]

The Initialize method in System.Windows.Interop.HwndSource will check the StylusLogic.IsPointerStackEnabled as the code:

            if (StylusLogic.IsStylusAndTouchSupportEnabled)
            {
                // Choose between Wisp and Pointer stacks
                if (StylusLogic.IsPointerStackEnabled)
                {
                	// Enable the pointer support.
                    _stylus = new SecurityCriticalDataClass<IStylusInputProvider>(new HwndPointerInputProvider(this));
                }
                else
                {
                    _stylus = new SecurityCriticalDataClass<IStylusInputProvider>(new HwndStylusInputProvider(this));
                }
            }

Before enable the pointer support, it will enter the logic of HwndStylusInputProvider. And the HwndStylusInputProvider will return the flags when receive the WM_TABLET_QUERYSYSTEMGESTURESTATUS message in Hook.

       private IntPtr Hook(IntPtr hwnd, int msg, IntPtr wparam, IntPtr lparam, ref bool handled)
        {
            const int WM_TABLET_DEFBASE =0x02C0;
            const int WM_TABLET_QUERYSYSTEMGESTURESTATUS = WM_TABLET_DEFBASE + 12;
            const int WM_TABLET_FLICK = WM_TABLET_DEFBASE + 11;

            if (msg == WM_TABLET_QUERYSYSTEMGESTURESTATUS)
            {
                uint flags = 0;

                flags |= TABLET_PRESSANDHOLD_DISABLED;
                flags |= TABLET_TAPFEEDBACK_DISABLED;
                flags |= TABLET_TOUCHUI_FORCEON;
                flags |= TABLET_TOUCHUI_FORCEOFF;
                flags |= TABLET_FLICKS_DISABLED;

                handled = true;
                return new IntPtr(flags);
            }
            else if (msg == WM_TABLET_FLICK)
            {
                handled = true;
                return new IntPtr(1);
            }

            return IntPtr.Zero;
        }

        private const uint TABLET_PRESSANDHOLD_DISABLED = 0x00000001;
        private const uint TABLET_TAPFEEDBACK_DISABLED = 0x00000008;
        private const uint TABLET_TOUCHUI_FORCEON = 0x00000100;
        private const uint TABLET_TOUCHUI_FORCEOFF = 0x00000200;
        private const uint TABLET_FLICKS_DISABLED = 0x00010000;

But it will do nothing, although we add the hook manually, when we enable the pointer support.

See #3379

[bastio84]

Hello! Are there any news on this?
We are facing the same problem: we cannot figure out how to disable the right click press-and-hold behavior when we have Switch.System.Windows.Input.Stylus.EnablePointerSupport enabled.
Thanks a lot in advance for any help!

[lindexi]

@bastio84 Seems like the Windows limitation

[lindexi]

@bastio84 I find the soluction, see #3379 (comment)