So I'm beginning to create a program using DirectX11. I'm having a problem understanding why when I use IASetVertexBuffers() I get an error when I use 1 for the number of buffers in the array. But when I switch the value to 0 it loads just fine. It needs to have a value of 1.
BOOL Graphics::InitializeVertexBuffer(D3D11_USAGE Usage, INT BindFlags, INT CPUAccessFlags, INT MiscFlags)
{
D3D11_BUFFER_DESC D3D11BufferDesc;
D3D11BufferDesc.Usage = Usage;
D3D11BufferDesc.ByteWidth = sizeof(VERTEX) * 3;
D3D11BufferDesc.BindFlags = BindFlags;
D3D11BufferDesc.CPUAccessFlags = CPUAccessFlags;
D3D11BufferDesc.MiscFlags = MiscFlags;
D3D11Device->CreateBuffer(&D3D11BufferDesc, NULL, &VertexBuffer);
D3D11DeviceContext->IASetVertexBuffers(0, 0, &VertexBuffer, NULL, NULL);
return 1;
}
It needs to be as follows but I get an error
BOOL Graphics::InitializeVertexBuffer(D3D11_USAGE Usage, INT BindFlags, INT CPUAccessFlags, INT MiscFlags)
{
D3D11_BUFFER_DESC D3D11BufferDesc;
D3D11BufferDesc.Usage = Usage;
D3D11BufferDesc.ByteWidth = sizeof(VERTEX) * 3;
D3D11BufferDesc.BindFlags = BindFlags;
D3D11BufferDesc.CPUAccessFlags = CPUAccessFlags;
D3D11BufferDesc.MiscFlags = MiscFlags;
D3D11Device->CreateBuffer(&D3D11BufferDesc, NULL, &VertexBuffer);
D3D11DeviceContext->IASetVertexBuffers(0, 1, &VertexBuffer, NULL, NULL);
return 1;
}
You need to check the HRESULT for all Direct3D functions that return HRESULT rather than void. Use the SUCCEEDED or FAILED macros, or use the DX::ThrowIfFailed helper. Your code does nothing to check the HREUSLTs from CreateBuffer which is likely key.
Second, enable the Direct3D DEBUG device and look for errors or warnings in the debug output window. That usually points immediately to the problem with API usage or parameter validation. See this post.
Related
I am fairly new to kernel programming and I have a little problem getting all disk drives information like name,serialnumber from kernel mode. I use below code to get all disks symbolic links which works perfectly fine.
static VOID DeviceInterfaceTest_Func() {
NTSTATUS Status;
PWSTR SymbolicLinkList;
PWSTR SymbolicLinkListPtr;
GUID Guid = {
0x53F5630D,
0xB6BF,
0x11D0,
{
0x94,
0xF2,
0x00,
0xA0,
0xC9,
0x1E,
0xFB,
0x8B
}
}; //Defined in mountmgr.h
Status = IoGetDeviceInterfaces( &
Guid,
NULL,
0, &
SymbolicLinkList);
if (!NT_SUCCESS(Status)) {
return;
}
KdPrint(("IoGetDeviceInterfaces results:\n"));
for (SymbolicLinkListPtr = SymbolicLinkList; SymbolicLinkListPtr[0] != 0 && SymbolicLinkListPtr[1] != 0; SymbolicLinkListPtr += wcslen(SymbolicLinkListPtr) + 1) {
KdPrint(("Symbolic Link: %S\n", SymbolicLinkListPtr));
PUNICODE_STRING PTarget {};
UNICODE_STRING Input;
NTSTATUS s = 0;
Input.Length = sizeof((PWSTR) & SymbolicLinkListPtr);
Input.MaximumLength = 200 * sizeof(WCHAR);
Input.Buffer = (PWSTR) ExAllocatePool2(PagedPool, Input.MaximumLength, 0);
s = SymbolicLinkTarget( & Input, PTarget);
if (s == STATUS_SUCCESS) {
//KdPrint(("%S\n", PTarget->Buffer));
KdPrint(("Finished!\n"));
}
}
ExFreePool(SymbolicLinkList);
}
However when i try to use InitializeObjectAttributes function to extract data of symbolic link inside for loop I checking their names with KdPrint and all them are null as a result i can't use ZwOpenSymbolicLinkObject, because when i use it i get BSOD. What am I doing wrong? Is my method valid to get disk information or I should use another method? Below is the code of SymbolicLinkTarget
NTSTATUS SymbolicLinkTarget(_In_ PUNICODE_STRING SymbolicLinkStr, _Out_ PUNICODE_STRING PTarget) {
OBJECT_ATTRIBUTES ObjectAtiribute {};
NTSTATUS Status = 0;
HANDLE Handle = nullptr;
InitializeObjectAttributes( & ObjectAtiribute, SymbolicLinkStr, OBJ_CASE_INSENSITIVE, 0, 0);
KdPrint(("Object length:%u \n", ObjectAtiribute.Length));
KdPrint(("Object name:%s \n", ObjectAtiribute.ObjectName - > Buffer));
Status = ZwOpenSymbolicLinkObject(&Handle, GENERIC_READ, &ObjectAtiribute);
if (Status != STATUS_SUCCESS)
{
KdPrint(("ZwOpenSymbolicLinkObject failed (0x%08X)\n", Status));
return Status;
}
UNREFERENCED_PARAMETER(PTarget);
ULONG Tag1 = 'Tag1';
PTarget->MaximumLength = 200 * sizeof(WCHAR);
PTarget->Length = 0;
PTarget->Buffer = (PWCH)ExAllocatePool2(PagedPool, PTarget->MaximumLength, Tag1);
if (!PTarget->Buffer)
{
ZwClose(Handle);
return STATUS_INSUFFICIENT_RESOURCES;
}
Status = ZwQuerySymbolicLinkObject(Handle, PTarget, NULL);
ZwClose(Handle);
if (Status != STATUS_SUCCESS)
{
KdPrint(("ZwQuerySymbolicLinkObject failed (0x%08X)\n", Status));
ExFreePool(PTarget->Buffer);
return Status;
}
return STATUS_SUCCESS;
}
Thank you very much for helping.
There are multiple problems in your functions. Let start with he main one:
In SymbolicLinkTarget():
OBJECT_ATTRIBUTES ObjectAtiribute {};
InitializeObjectAttributes( & ObjectAtiribute, SymbolicLinkStr, OBJ_CASE_INSENSITIVE, 0, 0);
You are going to initialize ObjectAtiribute from SymbolicLinkStr (and the other parameters) but in DeviceInterfaceTest_Func() you actually never set Input to contain a string!
UNICODE_STRING Input;
NTSTATUS s = 0;
Input.Length = sizeof((PWSTR) & SymbolicLinkListPtr);
Input.MaximumLength = 200 * sizeof(WCHAR);
Input.Buffer = (PWSTR) ExAllocatePool2(PagedPool, Input.MaximumLength, 0);
s = SymbolicLinkTarget( & Input, PTarget);
Input.Length
This is wrong:
Input.Length = sizeof((PWSTR) & SymbolicLinkListPtr);
Input.Length will be set to the size of a pointer. According to the UNICODE_STRING (ntdef.h; subauth.h) the length is:
Specifies the length, in bytes, of the string pointed to by the Buffer member, not including the terminating NULL character, if any.
So:
size_t str_len_no_null = wcslen(SymbolicLinkListPtr); // number of chars, not bytes!
Input.Length = str_len_no_null * sizeof(WCHAR);
Notice the wcslen() is already in the init-statement of the for loop, I would train to extract it to have it in the loop body.
Input.MaximumLength
Input.MaximumLength = 200 * sizeof(WCHAR);
What if the string is more lager than 200 characters?
MaximumLength is defined as such:
Specifies the total size, in bytes, of memory allocated for Buffer. Up to MaximumLength bytes may be written into the buffer without trampling memory.
Thus it's safe to just do:
size_t max_length_bytes = Input.Length + (1 * sizeof(WCHAR)); // add room for possible null.
Input.MaximumLength = max_length_bytes;
The allocation for the Buffer member can be kept in place. Now you need to copy the string into the buffer.
UNICODE_STRING init
size_t str_len_no_null = wcslen(SymbolicLinkListPtr); // number of chars, not bytes!
Input.Length = str_len_no_null * sizeof(WCHAR);
size_t max_length_bytes = Input.Length + (1 * sizeof(WCHAR)); // add room for possible null.
Input.MaximumLength = max_length_bytes;
Input.Buffer = (PWSTR) ExAllocatePool2(PagedPool, Input.MaximumLength, 0); // note: you should define a Tag for your Driver.
if(Input.buffer == NULL) {
// not enough memory.
return;
}
status = RtlStringCbCopyW(Input.Buffer, max_length_bytes, SymbolicLinkListPtr);
// TODO: check status
Now that you know how to do it manually, throw your code and use RtlUnicodeStringInit
Other things & hints
Always checks the return status / value of the functions you use. In kernel mode, this is super important.
NTSTATUS check is always done using one of the status macros (usually NT_SUCCESS)
Use string safe functions.
nitpicking: A success return value of IoGetDeviceInterfaces may also indicate an empty buffer. Although you check that in the for loop init-statement, I would have checked that right after the function so the intent is clearer.
KdPrint(("Object name:%s \n", ObjectAtiribute.ObjectName - > Buffer));
It's %S (wide char) not %s (char); see format specification. you can pass a UNICODE_STRING and use the %Z formatter. Also be wary of - > which is strange (you probably meant ->).
InitializeObjectAttributes( & ObjectAtiribute, SymbolicLinkStr, OBJ_CASE_INSENSITIVE, 0, 0);
Use OBJ_CASE_INSENSITIVE | OBJ_KERNEL_HANDLE if the resulting handle is not meant to cross the kernel <-> user-mode boundary (in your case, it doesn't have to cross that boundary). Otherwise you leak a kernel handle to user-mode, which has security implications.
This is also required when you call ZwOpenSymbolicLinkObject and you are not running in a system thread:
If the caller is not running in a system thread context, it must set the OBJ_KERNEL_HANDLE attribute when it calls InitializeObjectAttributes.
You can define GUIDs with DEFINE_GUID; see Defining and Exporting New GUIDs and Including GUIDs in Driver Code. In your case you don't need to export it.
This is probably nitpicking, but use nullptr (c++) or NULL (c) instead of 0 to convey the idea that you are checking for a pointer and not just the integral value of 0.
I'm fetching the selected printer tray from a WIN32 call to PrintDlgEx(). This seems to work successfully most of the time, but recently I added a new printer to my machine (a DYMO LabelWriter 450) and it caused my simple software to fail.
Upon investigation, the call to DeviceCapabilities() for DC_BINS is returning 4294967295, while all of the other printers I've tested so far return single digit bin counts.
My first inclination is to omit the bin name when the bin count is greater than a given threshold (say... 20?), but I don't love this solution.
Is there a known reason that a printer would return the max UNSIGNED INT value for this? Is it just poorly written drivers, or is there an alternate meaning? Or perhaps I totally misunderstand the intended value.
If I have to write an arbitrary cap I will, but I'd like to better understand why this situation exists. Clearly, this printer doesn't have billions of different printer trays.
Here's an MRE:
HINSTANCE hinst = GetModuleHandle(NULL);
HRESULT hResult;
PRINTDLGEX pdx = {0};
LPPRINTPAGERANGE pPageRanges = NULL;
HWND hWndOwner = GetForegroundWindow();
if(!hWndOwner){
hWndOwner = GetDesktopWindow();
}
// Allocate an array of PRINTPAGERANGE structures.
pPageRanges = (LPPRINTPAGERANGE) GlobalAlloc(GPTR, 10 * sizeof(PRINTPAGERANGE));
if(!pPageRanges){
return wprintf(L"{\"error\": \"%s\"}", GetLastError()); // "Your computer does not have enough memory to complete this operation:"
}
// Initialize the PRINTDLGEX structure.
pdx.lStructSize = sizeof(PRINTDLGEX);
pdx.hwndOwner = hWndOwner;
pdx.hDevMode = NULL;
pdx.hDevNames = NULL;
pdx.hDC = NULL;
pdx.Flags = PD_RETURNDC | PD_COLLATE;
pdx.Flags2 = 0;
pdx.ExclusionFlags = 0;
pdx.nPageRanges = 0;
pdx.nMaxPageRanges = 10;
pdx.lpPageRanges = pPageRanges;
pdx.nMinPage = 1;
pdx.nMaxPage = 1000;
pdx.nCopies = 1;
pdx.hInstance = 0;
pdx.lpPrintTemplateName = NULL;
pdx.lpCallback = NULL;
pdx.nPropertyPages = 0;
pdx.lphPropertyPages = NULL;
pdx.nStartPage = START_PAGE_GENERAL;
pdx.dwResultAction = 0;
// Invoke the Print property sheet.
hResult = PrintDlgEx(&pdx);
DEVMODE * myDevMode = (DEVMODE *)GlobalLock(pdx.hDevMode);
DWORD binCount = DeviceCapabilities((CHAR*)myDevMode->dmDeviceName, nullptr, DC_BINS, nullptr, nullptr);
DWORD binNameCount = DeviceCapabilities((CHAR*)myDevMode->dmDeviceName, nullptr, DC_BINNAMES, nullptr, nullptr);
wprintf(L"\"binCount\":\"%lu\",", binCount);
wprintf(L"\"binNameCount\":\"%lu\",", binNameCount);
DeviceCapabilities() returns a signed int, not an unsigned DWORD.
The unsigned value 4294967295 is hex 0xFFFFFFFF, which is the same numeric value as a signed -1.
Per the DeviceCapabilities() documentation:
Return value
If the function succeeds, the return value depends on the setting of the fwCapability parameter. A return value of zero generally indicates that, while the function completed successfully, there was some type of failure, such as a capability that is not supported. For more details, see the descriptions for the fwCapability values.
If the function returns -1, this may mean either that the capability is not supported or there was a general function failure.
You are not accounting for the possibility of DeviceCapabilities() failing (or PrintDlgEx(), either).
Try this:
HWND hWndOwner = GetForegroundWindow();
if (!hWndOwner){
hWndOwner = GetDesktopWindow();
}
// Allocate an array of PRINTPAGERANGE structures.
LPPRINTPAGERANGE pPageRanges = (LPPRINTPAGERANGE) GlobalAlloc(GPTR, 10 * sizeof(PRINTPAGERANGE));
if (!pPageRanges){
// NOTE: GetLastError() returns DWORD, not TCHAR*! So, if you
// want to translate the error code in a human-readable string,
// use FormatMessage() instead...
return wprintf(L"{\"error\": %lu}", GetLastError());
}
// Initialize the PRINTDLGEX structure.
PRINTDLGEX pdx = {0};
pdx.lStructSize = sizeof(PRINTDLGEX);
pdx.hwndOwner = hWndOwner;
pdx.Flags = PD_RETURNDC | PD_COLLATE;
pdx.nMaxPageRanges = 10;
pdx.lpPageRanges = pPageRanges;
pdx.nMinPage = 1;
pdx.nMaxPage = 1000;
pdx.nCopies = 1;
pdx.nStartPage = START_PAGE_GENERAL;
HRESULT hResult = PrintDlgEx(&pdx);
if (hResult != S_OK)
{
GlobalFree(reinterpret_cast<HGLOBAL>(pPageRanges));
return wprintf(L"{\"error\": %d}", hResult);
}
if (pdx.dwResultAction == PD_RESULT_CANCEL)
{
GlobalFree(reinterpret_cast<HGLOBAL>(pPageRanges));
return wprintf(L"{\"error\": \"cancelled\"}");
}
DEVMODE *myDevMode = (DEVMODE*) GlobalLock(pdx.hDevMode);
int binCount = DeviceCapabilities(reinterpret_cast<TCHAR*>(myDevMode->dmDeviceName), nullptr, DC_BINS, nullptr, nullptr);
wprintf(L"\"binCount\":%d,", binCount);
int binNameCount = DeviceCapabilities(reinterpret_cast<TCHAR*>(myDevMode->dmDeviceName),
nullptr, DC_BINNAMES, nullptr, nullptr);
wprintf(L"\"binNameCount\":%d,", binNameCount);
if (binCount == -1)
{
...
}
if (binNameCount == -1)
{
...
}
...
GlobalUnlock(pdx.hDevMode);
GlobalFree(reinterpret_cast<HGLOBAL>(pPageRanges));
return ...;
GetWindowThreadProcessId(hwndFoundWindow, &dwTrayProcessID);
HANDLE hTrayProc = OpenProcess(PROCESS_ALL_ACCESS, 0, dwTrayProcessID);
int iButtonsCount = SendMessage(hwndFoundWindow, TB_BUTTONCOUNT, 0, 0);
LPVOID lpData = VirtualAllocEx(hTrayProc, NULL, sizeof(TBBUTTON), MEM_COMMIT, PAGE_READWRITE);
int iButton;
DWORD dwBytesRead;
TBBUTTON buttonData;
dwBytesRead = -1;
int chk_data = (int)SendMessage(hwndFoundWindow, TB_GETBUTTON, iButton, (LPARAM)lpData);
ReadProcessMemory(hTrayProc, lpData, &buttonData, sizeof(TBBUTTON), &dwBytesRead);
int len_text = (int)SendMessage(hwndFoundWindow, TB_GETBUTTONTEXTW, buttonData.idCommand, (LPARAM)lpData);
till now, i know the length of button's text but i also need to get the text to display on console.
my problem is i do not really know how to get that text from the button. please kindly help.
what i am trying is ... trying to access to lpData to get the string inside, but could not do that.
My first comment is that you need to add error checking to your code. As far as I can see, you perform no checking of return values. Any of the API functions you call could fail. If you don't check return values for errors then you have no way of diagnosing where you went wrong.
For instance, starting with GetWindowThreadProcessId, you need to write it like this:
if (GetWindowThreadProcessId(hwndFoundWindow, &dwTrayProcessID) == 0)
{
// handle error
}
And so on for all the other functions. Consult MSDN carefully to understand how each function signals failure.
Now to the main part of the question. I believe that it is the TB_GETBUTTONTEXTW message that is giving you trouble. You need to write it like this:
LRESULT len = SendMessage(hwndFoundWindow, TB_GETBUTTONTEXTW,
buttonData.idCommand, NULL);
if (len == -1)
{
// handle error
}
size_t size = sizeof(wchar_t)*(len+1);
LPVOID lpData = VirtualAllocEx(hTrayProc, NULL, size, MEM_COMMIT, PAGE_READWRITE);
if (lpData == NULL)
{
// handle error
}
len = SendMessage(hwndFoundWindow, TB_GETBUTTONTEXTW,
buttonData.idCommand, (LPARAM)lpData);
if (len == -1)
{
// handle error
}
wchar_t* str = new wchar_t[len+1];
if (!ReadProcessMemory(hTrayProc, lpData, (LPVOID)str, size, NULL))
{
// handle error
}
// the text is now in str, as a null-terminated UTF-16 string
delete[] str;
You need this: (see documentation of TB_GETBUTTONTEXTW).
WCHAR *buffer ;
int len_text = (int)SendMessage(hwndFoundWindow, TB_GETBUTTONTEXTW,
buttonData.idCommand, (LPARAM)NULL);
buffer = (WCHAR*)malloc(sizeof(WCHAR) * (len_text + 1)) ;
SendMessage(hwndFoundWindow, TB_GETBUTTONTEXTW,
buttonData.idCommand, (LPARAM)buffer);
....
free(buffer) ;
I am creating a multi-monitor full screen DXGI/D3D application. I am enumerating through the available outputs and adapters in preparation of creating their swap chains.
When creating my swap chain using DXGI's IDXGIFactory::CreateSwapChain method, I need to provide a swap chain description which includes a buffer description of type DXGI_MODE_DESC that details the width, height, refresh rate, etc. How can I find out what the output is currently set to (or how can I find out what the display mode of the output currently is)? I don't want to change the user's resolution or refresh rate when I go to full screen with this swap chain.
After looking around some more I stumbled upon the EnumDisplaySettings legacy GDI function, which allows me to access the current resolution and refresh rate. Combining this with the IDXGIOutput::FindClosestMatchingMode function I can get pretty close to the current display mode:
void getClosestDisplayModeToCurrent(IDXGIOutput* output, DXGI_MODE_DESC* outCurrentDisplayMode)
{
DXGI_OUTPUT_DESC outputDesc;
output->GetDesc(&outputDesc);
HMONITOR hMonitor = outputDesc.Monitor;
MONITORINFOEX monitorInfo;
monitorInfo.cbSize = sizeof(MONITORINFOEX);
GetMonitorInfo(hMonitor, &monitorInfo);
DEVMODE devMode;
devMode.dmSize = sizeof(DEVMODE);
devMode.dmDriverExtra = 0;
EnumDisplaySettings(monitorInfo.szDevice, ENUM_CURRENT_SETTINGS, &devMode);
DXGI_MODE_DESC current;
current.Width = devMode.dmPelsWidth;
current.Height = devMode.dmPelsHeight;
bool useDefaultRefreshRate = 1 == devMode.dmDisplayFrequency || 0 == devMode.dmDisplayFrequency;
current.RefreshRate.Numerator = useDefaultRefreshRate ? 0 : devMode.dmDisplayFrequency;
current.RefreshRate.Denominator = useDefaultRefreshRate ? 0 : 1;
current.Format = DXGI_FORMAT_R8G8B8A8_UNORM;
current.ScanlineOrdering = DXGI_MODE_SCANLINE_ORDER_UNSPECIFIED;
current.Scaling = DXGI_MODE_SCALING_UNSPECIFIED;
output->FindClosestMatchingMode(¤t, outCurrentDisplayMode, NULL);
}
...But I don't think that this is really the correct answer because I'm needing to use legacy functions. Is there any way to do this with DXGI to get the exact current display mode rather than using this method?
I saw solution here:
http://www.rastertek.com/dx11tut03.html
In folow part:
// Now go through all the display modes and find the one that matches the screen width and height.
// When a match is found store the numerator and denominator of the refresh rate for that monitor.
for(i=0; i<numModes; i++)
{
if(displayModeList[i].Width == (unsigned int)screenWidth)
{
if(displayModeList[i].Height == (unsigned int)screenHeight)
{
numerator = displayModeList[i].RefreshRate.Numerator;
denominator = displayModeList[i].RefreshRate.Denominator;
}
}
}
Is my understanding correct, the available resolution is in the displayModeList.
This might be what you are looking for:
// Get display mode list
std::vector<DXGI_MODE_DESC*> modeList = GetDisplayModeList(*outputItor);
for(std::vector<DXGI_MODE_DESC*>::iterator modeItor = modeList.begin(); modeItor != modeList.end(); ++modeItor)
{
// PrintDisplayModeInfo(*modeItor);
}
}
std::vector<DXGI_MODE_DESC*> GetDisplayModeList(IDXGIOutput* output)
{
UINT num = 0;
DXGI_FORMAT format = DXGI_FORMAT_R32G32B32A32_TYPELESS;
UINT flags = DXGI_ENUM_MODES_INTERLACED | DXGI_ENUM_MODES_SCALING;
// Get number of display modes
output->GetDisplayModeList(format, flags, &num, 0);
// Get display mode list
DXGI_MODE_DESC * pDescs = new DXGI_MODE_DESC[num];
output->GetDisplayModeList(format, flags, &num, pDescs);
std::vector<DXGI_MODE_DESC*> displayList;
for(int i = 0; i < num; ++i)
{
displayList.push_back(&pDescs[i]);
}
return displayList;
}
I have a list of items (potentially large) from which the user must select one. I'd like to allow the user to type the first few letters of the desired item to jump to the correct place in the list. By default, each keypress jumps to the first item starting with that letter, so you can't type the first several letters. Is there any straightforward way to do this? Any CodeProject or other such example?
I've looked for hours, and found any number of samples for IAutocomplete, but that won't help here because I need to guarantee that the result is in the list.
The only way I can think to do this is to derive from CListBox, capture the keystrokes myself, find the item, run a timer so that new keystrokes after a sufficient pause will start a new search... since I'm not an MFC jock, this is daunting. Any tips much appreciated.
One clarifying note: my ultimate goal is actually to get this keyboard behavior for a ComboBox of DropDownList style (i.e. no edit box). The lack of an edit box rules out most autocomplete code, and the need for ComboBox functionality means I can't use CListCtrl by itself.
After much unnecessary pain, I've discovered that the real correct answer is simply to use LBS_SORT. Simply by specifying this style, the basic vanilla listbox supports the incremental search keyboard shortcut style I wanted. Without LBS_SORT (or CBS_SORT for a combobox), you get the irritating and almost-useless jump-to-first-letter-only behavior. I didn't try LBS_SORT because my list contents were added in sorted order anyway.
So the dozen or so hours of investigating custom controls, etc., all for naught because the Microsoft documentation makes no mention of this important behavioral difference in the description of LBS_SORT!!
Thanks to everyone who contributed.
I've implemented such a functionality in core Win32. Heres the code.
Somewhere in your message loop that processes the list box insert:
switch(message)
{
case WM_CHAR:
if(HandleListBoxKeyStrokes(hwnd, wParam) == FALSE)
return FALSE;
....
Heres the code (propably not fully complete):
/* ======================================================================== */
/* ======================================================================== */
#define RETURNr(a, b) // homegrown asserts
BOOLEAN HandleListBoxKeyStrokes(HWND hwnd, UINT theKey)
{
#define MAXCHARCACHEINTERVALL 600.0 // Max. milisecs time offset to consider as typed 'at once'
static char sgLastChars[255] = {'0'};
static double sgLastCharTime = 0.;
static HWND sgLasthwnd = NULL;
if(GetSecs() - sgLastCharTime > MAXCHARCACHEINTERVALL ||
sgLasthwnd != hwnd)
*sgLastChars = 0;
if(theKey == ' ' && *sgLastChars == 0)
return TRUE;
sgLastCharTime = GetSecs();
sgLasthwnd = hwnd;
AppendChar(sgLastChars, toupper(theKey));
if(strlen(sgLastChars) > 1)
{
LONG l = GetWindowLong(hwnd, GWL_STYLE);
Char255 tx;
GetClassName(hwnd, tx, sizeof(tx));
if( (! stricmp(tx, "Listbox") &&
! (l & (LBS_EXTENDEDSEL | LBS_MULTIPLESEL)) ) ||
(! stricmp(tx, "ComboBox") && // combo Box support
l & CBS_DROPDOWNLIST &&
! (l & (CBS_OWNERDRAWFIXED | CBS_OWNERDRAWVARIABLE)) ) )
{
long Count, l, BestMatch = - 1, BestMatchOff = 0;
long LBcmdSet[] = {LB_GETCOUNT, LB_GETTEXTLEN , LB_GETTEXT};
long CBcmdSet[] = {CB_GETCOUNT, CB_GETLBTEXTLEN, CB_GETLBTEXT};
long *cmdSet = (! stricmp(tx, "ComboBox")) ? CBcmdSet : LBcmdSet;
RETURNr((Count = SendMessage(hwnd, cmdSet[0], 0, 0)) != LB_ERR, 0);
for(int i = 0; i < Count; i++)
{
RETURNr((l = SendMessage(hwnd, cmdSet[1], i, 0)) != LB_ERR, TRUE);
RETURNr( l < sizeof(tx), TRUE);
RETURNr((l = SendMessage(hwnd, cmdSet[2], i, (LPARAM)&tx)) != LB_ERR, TRUE);
strupr(tx);
if(! strncmp(tx, sgLastChars, strlen(sgLastChars)))
{
SelListBoxAndNotify(hwnd, i);
return FALSE;
}
char *p;
if(p = strstr(tx, sgLastChars))
{
int off = p - tx;
if(BestMatch == -1 || off < BestMatchOff)
{
BestMatch = i;
BestMatchOff = off;
}
}
}
// If text not found at start of string see if it matches some part inside the string
if(BestMatch != -1)
SelListBoxAndNotify(hwnd, BestMatch);
// Nothing found - dont process
return FALSE;
}
}
return TRUE;
}
/* ======================================================================== */
/* ======================================================================== */
void SelListBoxAndNotify(HWND hwnd, int index)
{
// i am sorry here - this is some XVT-toolkit specific code.
// it has to be replaced with something similar for native Win32
WINDOW win = xvtwi_hwnd_to_window(hwnd);
WINDOW parent = xvt_vobj_get_parent(win);
xvt_list_set_sel(win, index, 1);
EVENT evt;
memset(&evt, 0, sizeof(evt));
evt.type = E_CONTROL;
evt.v.ctl.id = GetDlgCtrlID(hwnd);
evt.v.ctl.ci.v.lbox.dbl_click = FALSE;
xvt_win_dispatch_event(parent, &evt);
}
/* ======================================================================== */
/* ======================================================================== */
double GetSecs(void)
{
struct timeb timebuffer;
ftime(&timebuffer);
return (double)timebuffer.millitm +
((double)timebuffer.time * 1000.) - // Timezone needed for DbfGetToday
((double)timebuffer.timezone * 60. * 1000.);
}
/* ======================================================================== */
/* ======================================================================== */
char AppendChar(char *tx, char C)
{ int i;
i = strlen(tx);
tx[i ] = C;
tx[i + 1] = 0;
return(C);
}
Can you use a CListView CListCtrl instead? They work like that by default.