I'm trying to autosize some date-time picker controls with DTM_GETIDEALSIZE, but I don't quite get how to use this message properly. While widths returned seem to be fine if treated as pixels, heights seem to be not only way off, but sometimes change over time!
The sample program below creates three date-time pickers. The first shows both date and time with a custom format, the second shows dates only with DTS_SHORTDATECENTURYFORMAT, and the third shows times only with DTS_TIMEFORMAT. Resizing the window resizes all three pickers using DTM_GETIDEALSIZE. The widths seem to be fine. However, the heights of the first two are always 100, and the height of the last (the time picker) seems to start at 98 or so and decreases by two with each resize until it reaches 16, at which point it stays at 16.
This is tested both with Windows Vista and with Windows 7. Error checking in the below program is inconsistent (but some errors are not checked for the purposes of keeping this a simple test example). However, I will note that MSDN explicitly documents DTM_GETIDEALSIZE as only ever returning TRUE with no error condition specified.
Thanks.
// 3 june 2015
#define UNICODE
#define _UNICODE
#define STRICT
#define STRICT_TYPED_ITEMIDS
#define CINTERFACE
#define WINVER 0x0600
#define _WIN32_WINNT 0x0600
#define _WIN32_WINDOWS 0x0600
#define _WIN32_IE 0x0700
#define NTDDI_VERSION 0x06000000
#include <windows.h>
#include <commctrl.h>
#include <stdint.h>
#include <uxtheme.h>
#include <string.h>
#include <wchar.h>
#include <windowsx.h>
#include <vsstyle.h>
#include <vssym32.h>
#include <stdarg.h>
#include <oleacc.h>
#include <stdio.h>
void die(char *s)
{
// TODO
}
HWND mainwin;
HWND dtp1, dtp2, dtp3;
void idealsize(HWND dtp, char *n, int *x, int *y)
{
SIZE s;
s.cx = 0;
s.cy = 0;
printf("%s | %I32d ", n, SendMessageW(dtp, DTM_GETIDEALSIZE, 0, (LPARAM) (&s)));
printf("%I32d %I32d\n", s.cx, s.cy);
MoveWindow(dtp, *x, *y, s.cx, s.cy, TRUE);
*y += s.cy;
}
LRESULT CALLBACK wndProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
int x, y;
SIZE s;
switch (uMsg) {
case WM_CLOSE:
PostQuitMessage(0);
return 0;
case WM_SIZE:
x = 10;
y = 10;
idealsize(dtp1, "1", &x, &y);
idealsize(dtp2, "2", &x, &y);
idealsize(dtp3, "3", &x, &y);
break;
}
return DefWindowProcW(hwnd, uMsg, wParam, lParam);
}
static HWND makedtp(DWORD style, WCHAR *format)
{
HWND hwnd;
hwnd = CreateWindowExW(WS_EX_CLIENTEDGE,
DATETIMEPICK_CLASSW, L"",
style | WS_TABSTOP | WS_CHILD | WS_VISIBLE,
0, 0, 100, 100,
mainwin, NULL, GetModuleHandle(NULL), NULL);
if (format != NULL)
if (SendMessageW(hwnd, DTM_SETFORMAT, 0, (LPARAM) format) == 0)
die("error applying format string to date/time picker in finishNewDateTimePicker()");
return hwnd;
}
#define GLI(what, buf, n) GetLocaleInfoEx(LOCALE_NAME_USER_DEFAULT, what, buf, n)
HWND makeDateTimePicker(void)
{
WCHAR *date, *time, *datetime;
int ndate, ntime;
int n;
HWND hwnd;
// TODO verify that this always returns a century year
ndate = GLI(LOCALE_SSHORTDATE, NULL, 0);
if (ndate == 0)
die("error getting date string length in uiNewDateTimePicker()");
date = (WCHAR *) malloc(ndate * sizeof (WCHAR));
if (GLI(LOCALE_SSHORTDATE, date, ndate) == 0)
die("error geting date string in uiNewDateTimePicker()");
ntime = GLI(LOCALE_STIMEFORMAT, NULL, 0);
if (ndate == 0)
die("error getting time string length in uiNewDateTimePicker()");
time = (WCHAR *) malloc(ntime * sizeof (WCHAR));
if (GLI(LOCALE_STIMEFORMAT, time, ntime) == 0)
die("error geting time string in uiNewDateTimePicker()");
n = _scwprintf(L"%s %s", date, time);
datetime = (WCHAR *) malloc((n + 1) * sizeof (WCHAR));
snwprintf(datetime, n + 1, L"%s %s", date, time);
hwnd = makedtp(0, datetime);
free(datetime);
free(time);
free(date);
return hwnd;
}
HWND makeDatePicker(void)
{
return makedtp(DTS_SHORTDATECENTURYFORMAT, NULL);
}
HWND makeTimePicker(void)
{
return makedtp(DTS_TIMEFORMAT, NULL);
}
static void makeWindows(void)
{
mainwin = CreateWindowExW(0,
L"mainwin", L"Full Window",
WS_OVERLAPPEDWINDOW,
CW_USEDEFAULT, CW_USEDEFAULT,
500, 500,
NULL, NULL, GetModuleHandle(NULL), NULL);
dtp1 = makeDateTimePicker();
dtp2 = makeDatePicker();
dtp3 = makeTimePicker();
}
void initCommonControls(BOOL);
int main(int argc, char *argv[])
{
WNDCLASSW wc;
MSG msg;
HBRUSH b;
initCommonControls(TRUE);
ZeroMemory(&wc, sizeof (WNDCLASSW));
wc.lpszClassName = L"mainwin";
wc.lpfnWndProc = wndProc;
wc.hInstance = GetModuleHandle(NULL);
wc.hIcon = LoadIconW(NULL, IDI_APPLICATION);
wc.hCursor = LoadCursorW(NULL, IDC_ARROW);
wc.hbrBackground = (HBRUSH) (COLOR_BTNFACE + 1);
RegisterClassW(&wc);
makeWindows();
ShowWindow(mainwin, SW_SHOWDEFAULT);
UpdateWindow(mainwin);
while (GetMessageW(&msg, NULL, 0, 0) > 0) {
TranslateMessage(&msg);
DispatchMessage(&msg);
}
return 0;
}
static const char manifest[] = "<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"yes\"?>\n<assembly xmlns=\"urn:schemas-microsoft-com:asm.v1\" manifestVersion=\"1.0\">\n<assemblyIdentity\n version=\"1.0.0.0\"\n processorArchitecture=\"*\"\n name=\"CompanyName.ProductName.YourApplication\"\n type=\"win32\"\n/>\n<description>Your application description here.</description>\n<dependency>\n <dependentAssembly>\n <assemblyIdentity\n type=\"win32\"\n name=\"Microsoft.Windows.Common-Controls\"\n version=\"6.0.0.0\"\n processorArchitecture=\"*\"\n publicKeyToken=\"6595b64144ccf1df\"\n language=\"*\"\n />\n </dependentAssembly>\n</dependency>\n</assembly>\n";
static ULONG_PTR comctlManifestCookie;
static HMODULE comctl32;
void initCommonControls(BOOL comctl6)
{
WCHAR temppath[MAX_PATH + 1];
WCHAR filename[MAX_PATH + 1];
HANDLE file;
DWORD nExpected, nGot;
ACTCTX actctx;
HANDLE ac;
INITCOMMONCONTROLSEX icc;
FARPROC f;
// this is listed as WINAPI in both Microsoft's and MinGW's headers, but not on MSDN for some reason
BOOL (*WINAPI ficc)(const LPINITCOMMONCONTROLSEX);
if (comctl6) {
if (GetTempPathW(MAX_PATH + 1, temppath) == 0)
die("getting temporary path for writing manifest file");
if (GetTempFileNameW(temppath, L"manifest", 0, filename) == 0)
die("getting temporary filename for writing manifest file");
file = CreateFileW(filename, GENERIC_WRITE,
0, // don't share while writing
NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
if (file == NULL)
die("creating manifest file");
nExpected = (sizeof manifest / sizeof manifest[0]) - 1; // - 1 to omit the terminating null character)
if (WriteFile(file, manifest, nExpected, &nGot, NULL) == 0)
die("writing manifest file");
if (nGot != nExpected)
die("short write to manifest file");
if (CloseHandle(file) == 0)
die("closing manifest file (this IS an error here because not doing so will prevent Windows from being able to use the manifest file in an activation context)");
ZeroMemory(&actctx, sizeof (ACTCTX));
actctx.cbSize = sizeof (ACTCTX);
actctx.dwFlags = ACTCTX_FLAG_SET_PROCESS_DEFAULT;
actctx.lpSource = filename;
ac = CreateActCtx(&actctx);
if (ac == INVALID_HANDLE_VALUE)
die("creating activation context for synthesized manifest file");
if (ActivateActCtx(ac, &comctlManifestCookie) == FALSE)
die("activating activation context for synthesized manifest file");
}
ZeroMemory(&icc, sizeof (INITCOMMONCONTROLSEX));
icc.dwSize = sizeof (INITCOMMONCONTROLSEX);
icc.dwICC = ICC_STANDARD_CLASSES | ICC_PROGRESS_CLASS | ICC_TAB_CLASSES | ICC_LISTVIEW_CLASSES | ICC_UPDOWN_CLASS | ICC_BAR_CLASSES | ICC_DATE_CLASSES;
comctl32 = LoadLibraryW(L"comctl32.dll");
if (comctl32 == NULL)
die("loading comctl32.dll");
f = GetProcAddress(comctl32, "InitCommonControlsEx");
if (f == NULL)
die("loading InitCommonControlsEx()");
ficc = (BOOL (*WINAPI)(const LPINITCOMMONCONTROLSEX)) f;
if ((*ficc)(&icc) == FALSE)
die("initializing Common Controls (comctl32.dll)");
}
