Execute a piece of code immediately after the dialog box is displayed.

 

Recently I was working on a project. When creating a subdialog box, the initialization was slow due to the large amount of code to be executed during OnInitDialog () initialization, it takes about 2 seconds for the dialog box to be displayed... so I want to display some code in the dialog box and then execute it. I found a lot of information on the Internet and summarized the following two methods. One is to set a timer in OnInitDilalog, in OnInitDialog (), PostMessage () reads the message Execution Code from the Message Queue after adding a custom message in the message queue waiting for the initialization of the dialog box. ,,,,

1. Create a timer only once before OnInitDialog returns, and execute code in OnTimer

BOOLMyAppDlg: OnInitDialog ()

{

..............................

// TODO: Add extra initialization here

 

SetTimer (m_nTimerID, 100, NULL );

ReturnTRUE; // return TRUE unless you set the focus to a control

}

 

VoidMyAppDlg: OnTimer (UINT_PTRnIDEvent)

{

If (nIDEvent = m_nTimerID)

{

// Execute the command only once, so Kill the command at the first time.

KillTimer (m_nTimerID );

M_nTimerID = 0;

AfxMessageBox (_ T ("Hello MFC "));

Return;

}

CDialog: OnTimer (nIDEvent );

}

2. post a custom message before OnInitDialog is returned, and execute the code in the corresponding function of the message.

# Define WM_MY_PRIVATE wm_user+ 1551

 

BOOLMyAppDlg: OnInitDialog ()

{

..............................

// TODO: Add extra initialization here

 

PostMessage (WM_MY_PRIVATE );

ReturnTRUE; // return TRUE unless you set the focus to a control

}

 

// Of course, you must add one in the message ing table

// ON_MESSAGE (WM_MY_PRIVATE, & CdummyDlg: OnPrivateMessage)

LRESULTMyAppDlg: OnPrivateMessage (WPARAM, LPARAM)

{

AfxMessageBox (_ T ("Hello MFC "));

Return0;

}