I want to be notified when user click the password text field.
But when I do click the password text field, the following function is called more than once:
void CUserDlg::OnSetfocusPasswordEdit()
{
// TODO: Add your control notification handler code here
cout << "focus on password text field";
}
Why does this happen ?
I also tried :
LRESULT CFakeUserDlg::WindowProc(UINT message, WPARAM wParam, LPARAM lParam)
{
// TODO: Add your specialized code here and/or call the base class
switch (message)
{
case WM_COMMAND:
switch (LOWORD(wParam))
{
case IDC_PASSWORD_EDIT:
if (HIWORD(wParam) == EN_SETFOCUS)
{
cout << "";
}
cout << "";
break;
}
.
.
.
This also happens many times when I click the text field only once.
I just tried to spy++, but it shows that spy++ caputure edit control messages, but EN_SETFOCUS is not message, it is edit control notification.
I got answer by myself.
Edit control does keep sending EN_SETFOCUS when it gets the focus.
Related
I'm barely a week into Win32 GUI programming, so I'm confident/hopeful this is something simple. For your consideration, I've provided a sample of my code below.
As a quick brief, my application watches for another application to be open so that I can modify that application's memory. I've placed this initial check at the top of my UI looper as follows such that it will only run once (in which case the user can only cancel and the app closes, or execution resumes past the if statement with hWndApp having a value assigned):
if (!hWndApp) {
appCheck();
}
If I start my application and the other application isn't running, appCheck(); fires and the waterfall of execution therefrom acts accordingly: a message box appears (and will keep appearing if the user clicks "Retry") until the other application's window is found. If the user clicks "Cancel," the application exits and all is well. If they click "Retry" once the other application is running, then my application will finish painting to the screen and execution is normal.
The funny business starts the next time I call appCheck(); (which happens when one of either two buttons is clicked) if the other application has been opened, then closed.
While debugging (via Visual Studio 2017), the variable I assign the MessageBox() call to equals 0 when the other application has been opened, then closed, then the following:
Push button to call appCheck();
getProcessHandleAndPID(); is then called within the if statement because the window can't be found
AppCheckMessageBox(); is then called within the while loop because the window can't be found
The debugger then points to the first line inside of AppCheckMessageBox();, which is the entire int msgboxID = MessageBox(); bit
Pressing F11 (Step Into), no window shows and the application exists after the default choice in the switch statement is triggered since the value of msgboxID is 0 (indicating the MessageBox() call failed, so I tried calling GetLastError() before exit(EXIT_FAILURE), but to no avail).
I'm not sure where my error lies, but I've sought many solutions--none of which have panned out. Finally, if you see any variables below that look misnamed or undeclared, it's solely due to my modification of the code for this post to try to generalize/ shorten it. I may have left out some global variable declarations, etc.
Thank you for any help/guidance you can provide! I'm at my wit's end with this right now...lol.
//--------------------------------------------------
// Function to get process handle and PID of app /
//------------------------------------------------
void getProcessHandleAndPID()
{
hWndApp = FindWindow(NULL, _T("NameOfApplication"));
while (!hWndApp) {
AppCheckMessageBox();
}
//Much more code here
}
//---------------------------------
// Function to show message box /
//-------------------------------
int AppCheckMessageBox()
{
int msgboxID = MessageBox(
NULL, //I tried making this hWndApp as well, but no difference
(LPCWSTR)L"Cancel to exit or start the app and click Retry.",
(LPCWSTR)L"Application Not Found!",
MB_ICONSTOP | MB_RETRYCANCEL | MB_SYSTEMMODAL | MB_SETFOREGROUND
);
switch (msgboxID)
{
case IDCANCEL:
exit(EXIT_FAILURE);
case IDRETRY:
getProcessHandleAndPID();
break;
default:
//GetLastError();
exit(EXIT_FAILURE);
}
return msgboxID;
}
//------------------------------------------------
// Function to check if application is running /
//----------------------------------------------
void appCheck() {
if (!FindWindow(NULL, _T("NameOfApplication"))) {
getProcessHandleAndPID();
}
}
//--------------------------------------------------
// Function to get process handle and PID of app /
//------------------------------------------------
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
if (!hWndApp) {
appCheck();
}
switch (message)
{
case WM_PAINT:
//Code here
break;
case WM_CREATE:
//Code here
break;
case WM_COMMAND:
switch (HIWORD(wParam))
{
case BN_CLICKED:
if (LOWORD(wParam) == BTN_ENABLE) {
appCheck();
//Do stuff with button press
}
if (LOWORD(wParam) == BTN_DISABLE) {
appCheck();
//Do stuff with button press
}
break;
}
break;
case WM_DESTROY:
PostQuitMessage(0);
break;
default:
return DefWindowProc(hWnd, message, wParam, lParam);
break;
}
return 0;
}
Not really an answer, but too long for comments:
This isn't your real code. Many things are missing, there are mismatched braces which would prevent compilation, etc. Always show your real code if you want help.
As David says, calling appCheck() every time you receive a message is the wrong approach. If you want to call it once after your window opens, do that before entering your message loop.
Your code is needlessly recursive (getProcessHandleAndPID() calls AppCheckMessageBox() which calls getProcessHandleAndPID() which calls...) and will potentially lead to a stack overflow.
I am using Visual Studio C++ 2010, and I need to detect current active page of Property Sheet. I expect there should be send some message to tell when user activated the Page. But I did not found that message and where to place it in dialog process.
In the program which I work with, there is this main dialog process:
INT_PTR CALLBACK MainDlgProc(HWND hSheet, UINT msg, WPARAM wParam, LPARAM lParam)
{
INT_PTR ret = FALSE;
switch (msg)
{
// bla bla
case WM_COMMAND:
ret = 0; //processing message
if (!Sheet_HandleCommand(hSheet, HIWORD(wParam), LOWORD(wParam), (HWND)lParam))
CALLPROC();
break;
case WM_DESTROY:
// bla bla
return CALLPROC();
default:
return CALLPROC();
}
return ret;
}
I know how to get the handle but I don't know where to "install" it in the code. What's the name of the message to include it into the MainDlgProc?
Use PSM_GETTABCONTROL (or the PropSheet_GetTabControl macro) to get a handle to the tab control, and then use the TCM_GETCURSEL message (or the TabCtrl_GetCurSel macro) to query the currently selected tab index.
Note this is documented not to work if using the Aero wizard style (PSH_AEROWIZARD), presumably because there is no tab control in that case.
In one of my dialog based MFC application, I've used two dialogs of similar look. The requirement is when user populates an edit box of one dialog with some data the same to be replicated to similar edit box of another dialog instantly. I'm trying to implement it with EN_CHANGE event of the edit control; where when any change is detected application post a message with updated data to other dialog to update the content of its own edit box. The problem is when the second dialog is setting its edit box content with the received data from first dialog, EN_CHANGE event is getting triggered from the second dialog, which is obvious, resulting in an endless back and forth message exchange. Could anybody please suggest me some solution for instant replicating user inputs between edit boxes of two MFC dialogs while keeping MFC application type as dialog based?
In my implementation both the Dialogs are CDialog derived and have the following CEdit event handler and Message handler methods:
For CScreen1 class:
void CScreen1::OnEnChangeEditUser()
{
static CString msg;
m_username.GetWindowText(msg);
::PostMessage(m_mScreen2,WM_INTER_LOGIN,10,(LPARAM)&msg); //m_mScreen2 is the HWND of 2nd dlg
}
LRESULT CScreen1::OnInterLoginMsg(WPARAM wParam, LPARAM lParam)
{
CString *msg=(CString*)lParam;
switch((int)wParam)
{
case 10:
m_username.SetWindowText(msg->GetString()); //m_username is CEdit Ctrl
delete msg;
break;
}
return 0;
}
For CScreen2 class:
void CScreen2::OnEnChangeEditUser()
{
static CString msg;
m_username.GetWindowText(msg);
::PostMessage(m_mScreen1,WM_INTER_LOGIN,10,(LPARAM)&msg); //m_mScreen1 is the HWND of 1st dlg
}
LRESULT CScreen2::OnInterLoginMsg(WPARAM wParam, LPARAM lParam)
{
CString *msg=(CString*)lParam;
switch((int)wParam)
{
case 10:
m_username.SetWindowText(msg->GetString()); //m_username is CEdit Ctrl
delete msg;
break;
}
return 0;
}
Simply use a boolean variable to play around. I have updated your code here.
For CScreen1 class:
BOOL postchanges = TRUE; //always TRUE
void CScreen1::OnEnChangeEditUser()
{
if (!postchanges)
return;
static CString msg;
m_username.GetWindowText(msg);
::PostMessage(m_mScreen2,WM_INTER_LOGIN,10,(LPARAM)&msg); //m_mScreen2 is the HWND of 2nd dlg
}
LRESULT CScreen1::OnInterLoginMsg(WPARAM wParam, LPARAM lParam)
{
CString *msg=(CString*)lParam;
switch((int)wParam)
{
case 10:
postchanges = FALSE; // do not post msg
m_username.SetWindowText(msg->GetString()); //m_username is CEdit Ctrl
postchanges = TRUE; // revert back
delete msg;
break;
}
return 0;
}
For CScreen2 class: do the same
As the requirement is replicating user input between two Edit controls of different Dialogs; it can be handled through processing keystroke messages.
I am writing my first simple program in C++/WINAPI, with a lot of check boxes and a few edit fields, which will set up some calculations on a button press. All of my check boxes work/store info through individual cases, ie
switch (msg)
{
...
case WM_COMMAND:
{
switch (wParam)
{
case IDBC_BoxCheck1:
{...}
case IDBC_BoxCheck2:
{...}
...
} ...
...but I assumed edit fields didn't work as a case statement like a button press, since the value has to be read at the end once it has been changed as many times as the user wants. I looked online and attempted to use the SendMessage(hwnd, ...) and GetWindowText(hwnd, ...) functions to send a WM_GETTEXT command to the edit field and store it to a lpstr string, but I ran into the same problem with both of them - the hwnd for the edit fields aren't declared in the scope where the WM_GETTEXT command is being sent from, and I'm not sure how to get it there. Here is an overview of the structure being used in my program, which comes from a mix of some tutorials I was working with:
LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
switch (msg)
{
case WM_CREATE:
{
return OnCreate(hwnd, reinterpret_cast<CREATESTRUCT*>(lParam));
// OnCreate is a sub function that handles the creation of all the buttons/controls,
// since there are so many of them, with the format:
// HWND editControl1 = CreateControl(...); // CreateControl being another sub fnct
// that creates edit field ctrls
// editControl1 is the hwnd I'm trying
// to read the value from
// HWND checkControl1 = CreateButton(...); // Creates button ctrls, including ck box
...
}
...
case WM_COMMAND:
{
switch (wParam)
{
case IDBC_BoxCheck1: // These control IDs are defined at the top of the file
{
LPSTR Check1;
StoreInfo(Check1); // Just a sub fnct to store info for later calculations
}
case IDBC_BoxCheck2:
{
LPSTR Check2;
StoreInfo(Check2);
} // etc... there are 20 or so check boxes/buttons
case IDBC_Calculate:
{
LPSTR edit1;
GetWindowText(editControl1, edit1, 100); // or SendMessage(editControl1, ...)
// This kicks out the error of editControl1 not being declared in this scope
StoreInfo(edit1);
// Calculation function goes here
} ...
} ....
}
default: DefWindowProc(hwnd, msg, wParam, lParam);
}
}
IDBC_Calculate is the final button pressed before the calculations run. I figured the best place to read and store the values from the edit fields would be after this button is pressed, right before the calculation function is called, but tied to the same command. This is where the hwnd editControl1 is undefined, but I don't know how to send the definition to this scope, or where else I should be reading and storing the edit field values.
Any help or pointers on getting the values from these edit fields to my other functions would be appreciated! I've seen many different ways to check button states in various tutorials/lessons, so I'd love to know if there's a better way to do what I've written above in general.
Your edit fields have IDs right? Then you can use GetDlgItem.
editControl1 = GetDlgItem(hwnd, CONTROL_ID_1);
GetDlgItem is badly named, it doesn't just work in dialog boxes. It gets the handle of any child window from a parent window, using the ID of the child window.
And what Anders K says is correct. The way you are using GetWindowText will crash your program.
I want to detect when any control on a dialog box is changed by user action. For example, when data is entered in a text box, a date is entered in a date-time picker, a check box is checked or unchecked, etc. Up to now I have ignored such notifications and simply retrieved the state of the controls when the user pushes some button but now I want to know a change has taken place (I want to enable the Apply button on a property sheet). I don't really care what change has taken place, all I want to know is that something has changed. By change I do NOT mean a change in focus but some actual action by the user to change a control.
I use plain old c++, no MFC or anything fancy.
How do I go about this?
You can test whether a checkbox has been checked with the BN_CLICKED notification code which you'd get through WM_COMMAND.
switch( uMsg ) {
...
case WM_COMMAND: {
switch( HIWORD( wParam ) ) {
case BN_CLICKED: {
if( Button_GetCheck( lParam ) == BST_CHECKED ) {
...
}
break;
}
default:
return false;
}
break;
}
default:
return false;
}
return true;
That is an example of how your DialogProc might be set up. You can switch on lParam or LOWORD( wParam ) to identify which button.