C / C++ / MFC

Quote:

I am using windows 10 & VS2017.

BOOL CTesterDlg::OnDeviceChange(UINT nEventType, DWORD_PTR dwPtrData)
{
	BOOL bReturn = CWnd::OnDeviceChange(nEventType, dwPtrData);

	PDEV_BROADCAST_DEVICEINTERFACE b = (PDEV_BROADCAST_DEVICEINTERFACE)dwPtrData;

	if(b != NULL)
	{
		CString Msg;
		Msg.Format(L"%s",b->dbcc_name);
		MessageBox(Msg);
	}

	switch (nEventType)
	{
		case DBT_DEVICEARRIVAL:
			if(hComm==INVALID_HANDLE_VALUE) DeviceInit();
			break;
		case DBT_DEVICEREMOVECOMPLETE:
			ClosePort();
			break;
	}

	return bReturn;
}

Member 13899178 wrote:

However, always when I try to print out the dbcc_name, its length is one wide character (as defined in the structure documentation) and nothing more prints out.
...
Please advise.

// FTDI_D2XX_Device Class GUID
// To be used with RegisterDeviceNotification()
/*static*/ const GUID CTesterDlg::GUID_DEVINTERFACE_FTDI_D2XX =
{ 0x219D0508, 0x57A8, 0x4FF5, { 0x97, 0xA1, 0xBD, 0x86, 0x58, 0x7C, 0x6C, 0x7E }};

BOOL CTesterDlg::OnDeviceChange(UINT nEventType, DWORD_PTR dwPtrData)
{
    BOOL bReturn = CWnd::OnDeviceChange(nEventType, dwPtrData);

    PDEV_BROADCAST_DEVICEINTERFACE b = reinterpret_cast<PDEV_BROADCAST_DEVICEINTERFACE>(dwPtrData);
    // Check if dwPtrData is not NULL and for type BROADCAST_DEVICEINTERFACE.
    // When having registered an event with a GUID, that should be also compared here.
    // Comparing the GUID must be done when having registered multiple events.
    if (b && 
        b->dbcc_devicetype == DBT_DEVTYP_DEVICEINTERFACE &&
        b->dbcc_classguid == GUID_DEVINTERFACE_FTDI_D2XX)
    {
        //MessageBox(b->dbcc_name);

        // Handle events here
        // switch (nEventType)
    }
    return bReturn;
}

Quote:

When this structure is returned to a window through the WM_DEVICECHANGE message, the dbcc_name string is converted to ANSI as appropriate.

// Log using the full name from device change notification.
App()->Log(TRACE_LOG_DEBUG,
    _T("Device %s has been %s"), 
    pDev->dbcc_name,
    nEventType == DBT_DEVICEARRIVAL ? _T("added") : _T("removed"));

// Assume port changing (serial or parallel). The devicetype field is part of header of all structures.
// The name passed here is always the COM port name (even with virtual ports).
// Note that dwData may be NULL.
PDEV_BROADCAST_PORT pPort = reinterpret_cast<PDEV_BROADCAST_PORT>(dwData);
if (pPort && DBT_DEVTYP_PORT == pPort->dbcp_devicetype)
{
    // pPort->dbcp_name is "COMx" or "LPTx"
}

Quote:

To change gamma, cycle into ramp buffer and change RGB color where Gamma is the float factor.

WORD ramp[256*3];
for( int i=0; i<256; i++ ) {
    ramp[i+0] = ramp[i+256] = ramp[i+512] = 
    (WORD)min(65535, max(0, pow((i+1) / 256.0, Gamma) * 65535 + 0.5));
}
SetDeviceGammaRamp(::GetDC(NULL), ramp);

Quote:

But you do know that this is the C/C++ board and Java would be off topic?

Quote:

However, all you have to do is converting the Algorithm to Java