Question

I installed the Synaptics driver, therefore I can disable/enable the touchpad by hand.

Here is the way I’m using to enable/disable touchpad by C#:

private void Switch_Mouse(int i = 0) // 1: Enable, 0: Disable
{
    Process.Start("control.exe", "main.cpl");
    Thread.Sleep(1000);
    int iHandle = FindWindow(null, "Mouse Properties");
    SetForegroundWindow(iHandle); // Line ABC
    SendKeys.Send("^+{TAB}");
    if (i == 1)
    {
        SendKeys.Send("%E");
    }
    else
    {
        SendKeys.Send("%D");
        SendKeys.Send("{Enter}");
    }
    SendKeys.Send("%A");
    SendKeys.Send("{Enter}");
}

It sends keystrokes to the Mouse Properties. But after line labeled // ABC (above), the Mouse Properties app loses focus and it doesn’t work.

Is there any other way to enable/disable the trackpad by C#?

(OS: Window 32 bits).

Answer 1

This forum has a topic in which apparently the issue has been figured out (it’s all VB but porting to C# is quite straight-forward fortunately) -> Controlling Synaptics Touchpad

Looks like all touchpad-related handling starts here:

SynAPICtrl1.Initialize
  SynAPICtrl1.Activate ' Activate to receive device notifications
  DeviceHandle = SynAPICtrl1.FindDevice(SE_ConnectionAny, SE_DevicecPad, -1)
  If DeviceHandle = -1 Then
    MsgBox "Unable to find a Synaptics cPad"
    End
  End If

  SynDeviceCtrl1.Select (DeviceHandle)
  SynDeviceCtrl1.Activate 'Activate to receive pointing packets

  ZTouchThreshold = SynDeviceCtrl1.GetLongProperty(SP_ZTouchThreshold)

It’s taken from the Synaptics SDK which, as they state, is available here Synaptics SDK along with Developer Manuals