I've a Button made using Win32Api that I want to be able to notify whenever the user put the mouse inside the button rectangle.
I noticed that when user does that the WM_NOTIFY is called but I don't know which flag to use for ensure that the user has the mouse inside it's area.
Here is my button:
HWND Button = CreateWindow("BUTTON", "Test",
WS_VISIBLE | WS_CHILD | BS_DEFPUSHBUTTON | BS_NOTIFY,
20, 240, 120, 20,
hwnd, (HMENU)101, NULL, NULL);
And my WndProc:
LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
switch (msg)
{
case WM_NOTIFY:
{
//??? Here is where I want to do it
}
case WM_CREATE: //On Window Create
{
wHWND = hwnd;
if (onCreate != NULL)
onCreate(hwnd);
break;
}
case WM_COMMAND: //Command execution
{
//...
break;
}
case WM_DESTROY: //Form Destroyed
{
if (onDestroy != NULL)
onDestroy(hwnd);
PostQuitMessage(0);
break;
}
}
return DefWindowProc(hwnd, msg, wParam, lParam);
}
I don't know if I'm in the right path using WM_NOTIFY or not, maybe there is an easier way to do that. Thank you!
Try catching the WM_SETFOCUS message instead if you want a generic way of tracking focus.
BN_SETFOCUS is sent as WM_COMMAND in the upper 16 bits of WPARAM (HIWORD):
The parent window of the button receives this notification code through the WM_COMMAND message
If you are not talking about focus but just the mouse position then you can use ChildWindowFromPointEx or RealChildWindowFromPoint and a timer.
Related
I've written a code that dynamically creates a POPUP style window when the user clicks inside my main app window. Now I'd like the POPUP window to be automatically destroyed when the mouse cursor goes out of the POPUP wnd region. I know that i have probably handle the WM_MOUSEMOVE message but how to do that? Please provide a simple code for that if You can...
Use the WM_MOUSELEAVE message instead. However, note that this message has to be explicitly requested via TrackMouseEvent(), which your window can call when it receives its first WM_MOUSEMOVE message.
As #Remy Lebeau said, the following is the code implementation.
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
static BOOL Tracing = FALSE;
switch (message)
{
case WM_MOUSELEAVE:
{
DestroyWindow(hWnd);
break;
}
case WM_MOUSEMOVE:
{
if (!Tracing)
{
Tracing = TRUE;
TRACKMOUSEEVENT tme{};
tme.cbSize = sizeof(TRACKMOUSEEVENT);
tme.dwFlags = TME_LEAVE;
tme.hwndTrack = hWnd;
TrackMouseEvent(&tme);
}
break;
}
default:
return DefWindowProc(hWnd, message, wParam, lParam);
}
return 0;
}
you can compare the event.target and event.currentTarget, if both are same then you are out side of popup window else in side the popup window.
I try to change standart WndProc function. I have this code:
HWND btn = CreateWindowEx(WS_EX_TRANSPARENT | WS_EX_CLIENTEDGE, L"BUTTON", L"Window title", WS_TABSTOP | WS_VISIBLE | WS_CHILD | BS_DEFPUSHBUTTON
, 50, 50, 50, 50, (HWND)XApplicationMainWindow->window->_wnd, (HMENU)123,
(HINSTANCE)GetWindowLongPtr(XApplicationMainWindow->window->_wnd, GWLP_HINSTANCE), NULL);
SetWindowLongPtrW(btn, GWLP_WNDPROC, (LONG_PTR)SubclassWindowProc);
I can use L"BUTTON" class name, but when I change WndProc function I'll have a problem.
On this picture, you can see the blank square and normal button. If I try to create new WNDCLASS or WNDCLASSEX, I'll have nothing... Why?
How can I change the standart WndProc function, if I use L"BUTTON" class name?
It's my second WndProc:
LRESULT CALLBACK SubclassWindowProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam) {
switch (uMsg) {
case WM_CREATE:
break;
case WM_COMMAND:
//Event click
switch (LOWORD(wParam))
{
case 123:
OutputDebugStringA("Subclass click2");
break;
default:
break;
}
break;
default:
return DefWindowProc(hWnd, uMsg, wParam, lParam);
}
return 0;
}
DefWindowProc() is the wrong window procedure for your SubclassWindowProc() to be calling.
You need to call the previous window procedure that you are replacing - the window procedure that handles all of the button's default behaviors (like drawing the button so it actually looks like a button, and responding to user input like a button, etc). SetWindowLongPtr() returns a pointer to that procedure to you, but you are currently ignoring it.
See Subclassing Controls on MSDN for more details.
Try this instead:
WNDPROC btnWndProc;
LRESULT CALLBACK SubclassWindowProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam) {
switch (uMsg) {
case WM_COMMAND:
//Event click
switch (LOWORD(wParam))
{
case 123:
OutputDebugStringA("Subclass click2");
break;
}
break;
}
return CallWindowProc(hWnd, btnWndProc, uMsg, wParam, lParam);
}
...
HWND btn = CreateWindowEx(...);
btnWndProc = (WNDPROC) SetWindowLongPtrW(btn, GWLP_WNDPROC, (LONG_PTR)SubclassWindowProc);
Alternatively, using SetWindowSubclass(), which is safer than using SetWindowsLongPtr(), eg:
LRESULT CALLBACK SubclassWindowProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam, UINT_PTR uIdSubclass, DWORD_PTR dwRefData) {
switch (uMsg) {
case WM_NCDESTROY:
RemoveWindowSubclass(hWnd, SubclassWindowProc, uIdSubclass);
break;
case WM_COMMAND:
//Event click
switch (LOWORD(wParam))
{
case 123:
OutputDebugStringA("Subclass click2");
break;
}
break;
}
return DefSubclassProc(hWnd, uMsg, wParam, lParam);
}
...
HWND btn = CreateWindowEx(...);
SetWindowSubclass(btn, SubclassWindowProc, 1, 0);
Now, that being said, your subclass will never call OutputDebugStringA(), because it will never receive the WM_COMMAND message you are expecting. When a button is clicked, a WM_COMMAND message is not sent to the button itself. The button posts a WM_COMMAND message to the button's parent window instead (in this case, to XApplicationMainWindow->window->_wnd). So, you need to handle the WM_COMMAND message in the window procedure of the parent window, not in the window procedure of the button itself.
Otherwise, if you still want to subclass the button itself, you will have to handle the WM_LBUTTON(DOWN|UP) and WM_KEY(DOWN|UP)/WM_CHAR messages that the button receives and then subsequently translates into a WM_COMMAND message for its parent window.
So my program works, all apart from one thing, I would like for my button, 'pushBtn' , aka BTN_PUSH_TALK , to send a BN_PUSHED or BN_UNPUSHED message so I can handle it accordingly.
Following steps online, as well as trial and improvement, right now the only response I ever get is once I am done holding / clicking the button.
pushBtn = CreateWindowEx(0, L"BUTTON", L"TALK", WS_CHILD |
WS_VISIBLE |
BS_DEFPUSHBUTTON , 0 , 290 , 50, 50,
hWnd,(HMENU)BTN_PUSH_TALK, GetModuleHandle(NULL), NULL);
Handler (or at least what matters) :
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM
lParam)
{
bool asd;
switch (message)
{
case WM_COMMAND:
{
int wmId = LOWORD(wParam);
// Parse the menu selections:
switch (wmId)
{
case BTN_PUSH_TALK:
switch (HIWORD(wParam))
{
case BN_UNPUSHED:
if (connected && inputChoiceStr == "Push To Talk") {
tplug->setDuck(false);
}
break;
case BN_PUSHED:
if (connected && inputChoiceStr == "Push To Talk") {
tplug->setDuck(true);
}
break;
}
break;
I expected once i clicked and held down the button , that the BN_PUSHED case would be entered, however it is not.
On letting go, I expect the BN_UNPUSHED case to be entered, but this was not the case either.
case BTN_PUSH_TALK is reached, meaning the button is identifiable, however the switch case within this block of code is never reached.
Buttons send WM_COMMAND on click. To achieve a push/release notification you must subclass the button class (SetWindowLongPtr() with GWLP_WNDPROC) and then handle WM_LBUTTONDOWN and WM_LBUTTONUP in your new Window Proc.
If I'm reading the question right, your goal is to get notifications when a standard push button is initially pushed by the user, whereas standard notification behavior of buttons only posts WM_COMMANDs on "clicks" where a click is the whole mouse down plus mouse up sequence.
Historically in order to get the BN_PUSHED and BN_UNPUSHED notifications in your WM_COMMAND handler you had to use the BS_NOTIFY window style when creating the button. However, if you read the documentation for BN_PUSHED or BN_UNPUSHED you will see
This notification code is provided only for compatibility with 16-bit versions of Windows earlier than version 3.0. Applications should use the BS_OWNERDRAW button style and the DRAWITEMSTRUCT structure for this task.
These were very old notifications that from what I can tell are not just deprecated but no longer even supported. You can do, however, as the documentation suggests: use an owner drawn button i.e. a button created with the BS_OWNERDRAW style.
This turns out to be more difficult than just creating the button with BS_NOTIFY turned on, because the button will no longer perform default painting by itself. Given this added chore, I'd recommend not doing it this way unless you want to custom paint your buttons anyway -- unless you happen to want some nonstandard visual look-and-feel for these buttons as well as nonstandard notification behavior. Otherwise, I would probably just do Win32 subclassing as someone else suggested to trap WM_LBUTTONDOWN etc. and then call the standard button WNDPROC after doing some action on the events i cared about.
Anyway the minimal owner drawn button that reports button down and button up events is like the following. (I post the button events as custom messages but you could do whatever you wish there)
#include <windows.h>
#define BTN_ID 101
#define WM_PUSHBUTTONDOWN WM_APP + 1
#define WM_PUSHBUTTONUP WM_APP + 2
HINSTANCE g_instance = 0;
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam);
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow)
{
g_instance = hInstance;
MSG msg = { 0 };
WNDCLASS wc = { 0 };
wc.lpfnWndProc = WndProc;
wc.hInstance = hInstance;
wc.hbrBackground = reinterpret_cast<HBRUSH>(COLOR_BACKGROUND);
wc.lpszClassName = L"owner_draw_btn";
if (!RegisterClass(&wc))
return -1;
if (!CreateWindow(wc.lpszClassName, L"foobar", WS_OVERLAPPEDWINDOW | WS_VISIBLE, 0, 0, 640, 480, 0, 0, hInstance, NULL))
return -1;
while (GetMessage(&msg, NULL, 0, 0)) {
TranslateMessage(&msg);
DispatchMessage(&msg);
}
return 0;
}
LRESULT HandleDrawItem(HWND hWnd, WPARAM wParam, LPARAM lParam)
{
auto* dis = reinterpret_cast<DRAWITEMSTRUCT*>(lParam);
if (dis->CtlType != ODT_BUTTON)
return 0;
auto style = (dis->itemState & ODS_SELECTED) ?
DFCS_BUTTONPUSH | DFCS_PUSHED :
DFCS_BUTTONPUSH;
auto rect = &dis->rcItem;
DrawFrameControl(dis->hDC, rect, DFC_BUTTON, style);
TCHAR text[512];
auto n = GetWindowText(dis->hwndItem, text, 512);
DrawText(dis->hDC, text, n, rect, DT_SINGLELINE | DT_VCENTER | DT_CENTER);
if (dis->itemAction == ODA_SELECT) {
PostMessage(
hWnd,
(dis->itemState & ODS_SELECTED) ? WM_PUSHBUTTONDOWN : WM_PUSHBUTTONUP,
dis->CtlID,
0
);
}
return 0;
}
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
switch (message)
{
case WM_CREATE:
CreateWindow(
L"button", L"foobar",
BS_OWNERDRAW | WS_CHILD | WS_VISIBLE,
10, 10, 150, 35, hWnd,
(HMENU) BTN_ID,
g_instance,
0
);
return 0;
case WM_DRAWITEM:
return HandleDrawItem(hWnd, wParam, lParam);
case WM_PUSHBUTTONDOWN:
OutputDebugString(L"Button down event\n");
break;
case WM_PUSHBUTTONUP:
OutputDebugString(L"Button up event\n");
break;
case WM_CLOSE:
PostQuitMessage(0);
return 0;
}
return DefWindowProc(hWnd, message, wParam, lParam);
}
I've got a C++ project in which I'm using the Winapi to develop a window with a button and I want to change the text of the button when it's being hovered. For example, changing "Click me" to "Click me NOW!", when hovered. I've tried searching but I've not found any good ways to do this.
I noticed that when user hovers, the WM_NOTIFY message is received, but I don't know how to ensure that it has been called by the mouse hover. I've found that I can use TrackMouseEvent to detect hovering, but it's limited to a period of time and I want to execute an action every time the user hovers the button.
Here is how I create a button:
HWND Button = CreateWindow("BUTTON", "Click me",
WS_VISIBLE | WS_CHILD | BS_DEFPUSHBUTTON | BS_NOTIFY,
20, 240, 120, 20,
hwnd, (HMENU)101, NULL, NULL);
And this my window procedure:
LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
switch (msg)
{
case WM_NOTIFY:
{
//??? Here is where I get a message everytime I hover the button, But I don't know any proper way to see if it has been executed by the button.
}
case WM_CREATE: //On Window Create
{
//...
}
case WM_COMMAND: //Command execution
{
//...
break;
}
case WM_DESTROY: //Form Destroyed
{
PostQuitMessage(0);
break;
}
}
return DefWindowProc(hwnd, msg, wParam, lParam);
}
Assuming you're using the common controls there is the BCN_HOTITEMCHANGE notification code for the WM_NOTIFY message. The message includes the NMBCHOTITEM structure, which includes information for whether the mouse is entering or leaving the hover area.
Here's an example:
LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
switch(msg)
{
case WM_NOTIFY:
{
LPNMHDR header = *reinterpret_cast<LPNMHDR>(lParam);
switch (header->code)
{
case BCN_HOTITEMCHANGE:
{
NMBCHOTITEM* hot_item = reinterpret_cast<NMBCHOTITEM*>(lParam);
// Handle to the button
HWND button_handle = header->hwndFrom;
// ID of the button, if you're using resources
UINT_PTR button_id = header->idFrom;
// You can check if the mouse is entering or leaving the hover area
bool entering = hot_item->dwFlags & HICF_ENTERING;
return 0;
}
}
return 0;
}
}
return DefWindowProcW(hwnd, msg, wParam, lParam);
}
You can check the code of the WM_NOTIFY message to see if it is a NM_HOVER message.
switch(msg)
{
case WM_NOTIFY:
if(((LPNMHDR)lParam)->code == NM_HOVER)
{
// Process the hover message
}
else if (...) // any other WM_NOTIFY messages you care about
{}
}
You can use simply SFML to do this.
Code:
RectangleShape button;
button.setPosition(Vector2f(50, 50));
button.setSize(Vector2f(100, 40));
button.setFillColor(Color::Green);
if(button.getGlobalBounds().contains(static_cast<Vector2f>(Mouse::getPosition(/*your
window name*/window)
{
button.setFillColor(Color::Red);
}
I created a button in c++ as follows:
HWND btn = CreateWindow(
"BUTTON",
"OK",
WS_TABSTOP | WS_VISIBLE | WS_CHILD | BS_DEFPUSHBUTTON,
10,
10,
100,
100,
hWnd,
NULL,
(HINSTANCE)GetWindowLong(hWnd, GWL_HINSTANCE),
NULL);
The button is displayed in the main window (hWnd) but I don't know how or where to give it an event handler. Any help please?
There are three ways to detect the button being clicked.
The preferred approach is to add a WM_COMMAND handler to the window procedure of the button's parent window. When the button is clicked, it sends a BN_CLICKED notification to its parent window. This is described in the MSDN documentation for buttons:
Handling Messages from a Button
Notification Messages from Buttons
If you are adding the button to a parent window that you do not own, you can subclass the parent window using SetWindowsLongPtr(GWL_WNDPROC) or SetWindowSubClass(), and then you can handle messages that are sent to it, such as BN_CLICKED. This only works if the subclassing code runs in the same thread that owns the parent window.
Alternatively, you can subclass the button itself and handle keyboard and mouse messages instead.
Another option is to set an event hook using SetWinEventHook() asking to receive EVENT_OBJECT_INVOKED events. In the event callback procedure, the provided hwnd, ID, and idChild parameters will identify the control that is being invoked, such as a clicked button.
When the button is clicked, it sends a BN_CLICKED notification message (carried by the WM_COMMAND message) to its parent window. The BN_CLICKED notification code is in the HIWORD of the wParam of the message. The LOWORD of the wParam of the message has the ID of the button. The lParam of the message has the HWND of the button. This is all in the online Windows docs. Google for BN_CLICKED.
Consider this pseudo code... it's from memory. Basically, add the stuff inside the WM_COMMAND case to the window procedure that you already have:
LRESULT WINAPI YourWindowProc(HWND hWnd, UINT nMsg, WPARAM wp, LPARAM lp)
{
switch (nMsg)
{
case WM_COMMAND:
{
switch (HIWORD(wp))
{
case BN_CLICKED:
{
switch (LOWORD(wp))
{
case IDC_BUTTON1: // or whatever the ID of your button is...
{
// do stuff for button...
break;
}
}
break;
}
}
break;
}
default:
return DefWindowProc(hWnd, nMsg, wp, lp);
}
return 0;
}
In the second-to-last parameter, type (HMENU)1
in the WNDPROC:
switch (uMsg)
{
case WM_COMMAND:
switch (wParam)
{
case 1:
// Code
}
}