I have following code which works in the main dialog, but cannot work in the second (or third) dialog. The thing is that I want each page of the tab control can show a embedded dialog, it's similar to property page.
First I create two dialog, IDD_DIALOG1 and IDD_DIALOG2.Then I change the style of them to child and border to None. After that I add CDialog class to each of them.
In my MainDialog.h, I have the following code:
#include "Dialog1.h"
#include "Dialog2.h"
...
public:
CDialog1 m_para1;
CDialog2 m_para2;
CTabCtrl m_TabCtrl;
In my MainDialog.cpp, I use the following code to embed the dialo in the OnInitDialog:
m_TabCtrl.InsertItem(0, _T("TAB1"));
m_TabCtrl.InsertItem(1, _T("TAB2"));
m_para1.Create(IDD_DIALOG1,GetDlgItem(IDD_MAINDIALOG));
m_para2.Create(IDD_DIALOG2,GetDlgItem(IDD_MAINDIALOG));
CRect rs;
m_TabCtrl.GetClientRect(&rs);
rs.top+=37;
rs.bottom+=8;
rs.left+=13;
rs.right+=7;
m_para1.MoveWindow(&rs);
m_para2.MoveWindow(&rs);
m_para1.ShowWindow(TRUE);
m_para2.ShowWindow(FALSE);
m_TabCtrl.SetCurSel(1);
By using this way, It can work in this case. But if I want to use this method in my SecondDialog, the non-main dialog, it cannot work. Can someone help me out? Thanks in advance.
When you create a modeless dialog box, try this:
m_para1.Create(IDD_DIALOG1,&m_TabCtrl);
m_para2.Create(IDD_DIALOG2,&m_TabCtrl);
The second parameter of the Create function is a point to the parent window object (of type CWnd) to which the dialog object belongs. The return type of the GetDlgItem function is HWND.
See following:
http://msdn.microsoft.com/en-us/library/tc46f3be.aspx
http://msdn.microsoft.com/en-us/library/kc6x1ya0.aspx
Related
I am using VS2008.
I have MFC dialog based application with split button control.
I want to display a list box on the BCN_DROPDOWN event of split button control. I dont know how to achieve it?
Reference to the documentation of the CSplitButton class: https://msdn.microsoft.com/en-us/library/bb514109.aspx
If you want to change default behaviour then use the override:
BEGIN_MESSAGE_MAP(CMySplitButton,
CSplitButton)
ON_NOTIFY_REFLECT(BCN_DROPDOWN, &CMySplitButton::OnDropDown)
END_MESSAGE_MAP()
(...)
afx_msg void OnDropDown(NMHDR* pNMHDR, LRESULT* pResult);
You can in this function show your listbox or whatever you like.
If the listbox you refer to the actual submenu (3) as shown in the documentation, then add a menu: https://msdn.microsoft.com/en-us/library/4b6tafew.aspx and set the resource ID for that menu into SetDropDownMenu() function
void SetDropDownMenu(
UINT nMenuId,
UINT nSubMenuId);
Good luck :)
You must add your menu into a resource.
Ex:IDR_MENU_BUTTON_ANY
Declare some Resource symbols for submenu. It will change *.rc and resource.h.
Your resource will look like:
IDR_MENU_BUTTON_ANY
BEGIN
POPUP "SampleMenu"
BEGIN
MENUITEM "Sub1", ID_SUB_MENU_1
MENUITEM "Sub2", ID_SUB_MENU_2
END
END
When you initialize your dialog. You should insert some code as below:
//Your split button
CMFCSplitButton m_btnAny;
//Set dropdown menu
m_btnAny.SetDropDownMenu(IDR_MENU_BUTTON_ANY, 0);
More, I found the following link. The author provided an example. It may help you.
http://codexpert.ro/blog/2013/02/01/split-button-control/#comment-22983
I have an MFC dialog based application that has 2 Dialogs: Main Dialog CMyDlgand Second dialog CMyDlg2.
On the main Dialog I add a Button "Go dialog 2". So I added a handler for the button so that when clicked it pops up the second dialog. Everything works fine But on the second Dialog I have added a Rich Edit Control from toolbox. I Added for it a variable. I also added a class for the second dialog.
Now If I run the Application I get the dialog one and if I pressed "Go to dialog 2" I got what I want. But I need at some point to change the font of the rich edit control but my program crashes.
So I overrided OnInitDialog and inside it do some changes to the control but program crashes. After debugging I found that the handle of rich edit is null?!
So how and where can I change the color or do some initializations to the control?
(I called AfxInitRichEdit2() in OnInitInstance())
BOOL CMyDlg2::OnInitDialog() {
m_richEdit.SetWindowText("Hello there!"); // program crashes because the handle m_richEdit is null.
return TRUE;
}
And this is the handler of button that creates the Dialog2 and that contains the rich edit control:
void CMyDlg::OnBnClickedButton1(){
CMyDlg2 theDlg;
theDlg.DoModal();
// TODO: Add your control notification handler code here
}
If I create the rich edit control programmatically then everything works fine because I create it at OnInitDialog and then it works fine but I need the one that is I added using the wizard toolbox.
*** The thing is that if I write:
m_richEdit.SetWindowText(""); // program crashes but if I wirte:
GetDlgItem(IDC_RICHEDIT221).SetWindowText(""); it works fine?
You probably have the following code inserted by wizard:
void DoDataExchange(CDataExchange* pDX)
{
CDialogEx::DoDataExchange(pDX);
DDX_Control(pDX, IDC_RICHEDIT22, m_richEdit);
}
This tells the dialog to associate m_richEdit with the dialog control IDC_RICHEDIT22. But this association is not performed until the base class method CDialog::OnInitDialog(); is called.
BOOL CMyDlg2::OnInitDialog()
{
//this line should work:
GetDlgItem(IDC_RICHEDIT22)->SetWindowText("Hello");
//this line won't work:
//m_richEdit.SetWindowText("Hello there!"); <- richedit's handle is NULL
//this line will subclass m_richEdit
//plus run other initialization
CDialog::OnInitDialog();
//m_richEdit is ready
m_richEdit.SetWindowText("Hello there!");
return TRUE;
}
It's recommended to put CDialog::OnInitDialog() int the first line, to make sure the initialization is done.
GetDlgItem works because the control IDC_RICHEDIT22 exists in the dialog template and you have a valid dialog handle. You are basically making a simple call based on WinAPI's GetDlgItem:
HWND hedit = ::GetDlgItem(m_hWnd, IDC_RICHEDIT22);
::SetWindowText(hedit, "Hello world");
There is no additional initialization needed.
But m_richEdit is just a C++ object, declared as CRichEditCtrl m_richEdit; The constructor for this C++ class doesn't do much besides setting m_hWnd to NULL.
Once it's associated with a valid window handle, we can begin using its windows methods such as CRichEdit::SetWindowText
I just tried to setup a small win32 project, and was just about to create a window.
I created a dialog in the resource designer and set up this class for my window:
#pragma once
#include "stdafx.h"
class TTTMainDialog : public CWindowImpl<TTTMainDialog>
{
public:
DECLARE_WND_CLASS(_T("TTTDlg"))
enum { IDD = IDD_TTT_DIALOG };
BEGIN_MSG_MAP_EX(MusicPlayerDialog)
MSG_WM_INITDIALOG(OnInitDialog);
MSG_WM_CLOSE(OnClose);
MSG_WM_DESTROY(OnDestroy);
END_MSG_MAP()
TTTMainDialog();
~TTTMainDialog();
private:
const BOOL OnInitDialog(const CWindow wndFocus, const LPARAM lInitParam);
void OnClose();
void OnDestroy();
};
As you can see, I added the window class declaration, I inherited CWindowImpl, I registered the dialog. I don't think I forgot something here.
In the class which is supposed to create the dialog, I tried to create it like this:
TTTMainDialog myDialog;
HWND handle = myDialog.Create(NULL);
myDialog.ShowWindow(nCmdShow);
However, the Create method does return NULL all the time. I checked the error code with GetLastError(), and it turns out i am getting error code 1406, or "ERROR_TLW_WITH_WSCHILD".
The msdn documentation says the following about this error:
"Cannot create a top-level child window."
I tried to google up on this, but there is not much to find.
If I had to take a guess I would say the problem is caused by some window class name details, but i'm really not sure.
Any advice?
You are trying to build a window class from wrong pieces.
The error is pretty descriptive: you are trying to create a parentless window with a WS_CHILD style and this does not work out.
You get the child style from default template parameter: CWindowImpl -> CWindowImplBaseT -> TWinTraits -> CControlWinTraits. CControlWinTraits is supposed for use with child control windows.
If you are going to use a dialog template (IDD_TTT_DIALOG) then the proper base class is CDialogImpl, which is already prepared to use proper window styles. Also, it has what it takes to create both modal and modeless dialogs. The latter act more like windows and are non-blocking but in the same time take dialog template resource with predefined controls.
Small example for CDialogImpl use
Or, another one
I am writing a small QT gui application where there is a QLineEdit in my mainwindow.ui and I want to display the entered text in a separate dialog and or window when a button is pressed.
Now, I have stored the input in a variable, and I am also able to show this string on a label within this same mainwindow,
void MainWindow::on_GoButton_clicked()
{
QString mytext = ui->lineEdit_1->text();
ui->label_1->setText(mytext);
}
Now, I want to open a popup dialog (can be a window also), for example SecDialog;
SecDialog secdialog;
secdialog.setModal(true);
secdialog.exec();
and display the text of mainwindow->mytext string variable in a label of the SecDialog. How can I do that ??? I know it is a basic level question, but I think it will help clear lot of my doubts reagrding moving values of variables in between forms and classes.
Situation
So this is your situation:
From your code, the dialog is a modal dialog:
SecDialog secdialog;
//secdialog.setModal(true); // It's not needed since you already called exec(), and the
// dialog will be automatically set to be modal just like what
// document says in Chernobyl's answer
secdialog.exec();
Solution
To make the dialog display the text from the Window,
the concept is to pass the information(text) from the Window
to the dialog, and use a setter function from the dialog to display it.
Like Floris Velleman's answer, he passed the mytext string (by reference) to a customized dialog constructor and called the setter theStringInThisClass(myString) at once.
The implementation detail of this function is complemented by Chernobyl's answer (use the name setLabelText instead):
void SecDialog::setLabelText(QString str)
{
ui->label->setText(str); // this "ui" is the UI namespace of the dialog itself.
// If you create the dialog by designer, it's from dialog.ui
// Do not confuse with the ui from mainwindow.ui
}
Chernobyl suggested another way which calls the setter in the slot function and it bypasses the need of defining another constructor, but basically the concept is the same:
void MainWindow::on_GoButton_clicked()
{
QString mytext = ui->lineEdit_1->text();
ui->label_1->setText(mytext);
SecDialog secdialog;
secdialog.setLabelText(myText); // display the text in dialog
secdialog.exec();
}
Comment
I try to illustrate the concept as clear as possible, because from my previous experience on your question, you just "copy & paste" codes from answers and took them as your final solution, which is not right. So I hope this summary could help you understand the concept and then you may write your own code.
This task can be easy done with getter/setter method or with signal and slot, but setter is more suitable here. In SecDialog header:
public:
void setLabelText(QString str);
//in cpp
void SecDialog::setLabelText(QString str)
{
ui->label->setText(str);//it is label dialog
}
Usage:
secDialog.setLabelText(myText);
Also line where you set modal to true is not necessary because
This property holds whether show() should pop up the dialog as modal
or modeless. By default, this property is false and show() pops up the
dialog as modeless. Setting his property to true is equivalent to
setting QWidget::windowModality to Qt::ApplicationModal. exec()
ignores the value of this property and always pops up the dialog as
modal.
Assuming SecDialog is a custom class with an interface file as well you might want to pass it as a constructor argument or pass it by using another function.
So in the SecDialog constructor you could have something like:
SecDialog::SecDialog(QWidget* parent, const QString& myString)
: QDialog(parent),
theStringInThisClass(myString)
{}
And then you could call it like:
SecDialog secdialog(this, mytext);
I want to make a simple 'About' modal dialog, called from Help->About application menu. I've created a modal dialog window with QT Creator (.ui file).
What code should be in menu 'About' slot?
Now I have this code, but it shows up a new modal dialog (not based on my about.ui):
void MainWindow::on_actionAbout_triggered()
{
about = new QDialog(0,0);
about->show();
}
Thanks!
You need to setup the dialog with the UI you from your .ui file. The Qt uic compiler generates a header file from your .ui file which you need to include in your code. Assumed that your .ui file is called about.ui, and the Dialog is named About, then uiccreates the file ui_about.h, containing a class Ui_About. There are different approaches to setup your UI, at simplest you can do
#include "ui_about.h"
...
void MainWindow::on_actionAbout_triggered()
{
about = new QDialog(0,0);
Ui_About aboutUi;
aboutUi.setupUi(about);
about->show();
}
A better approach is to use inheritance, since it encapsulates your dialogs better, so that you can implement any functionality specific to the particular dialog within the sub class:
AboutDialog.h:
#include <QDialog>
#include "ui_about.h"
class AboutDialog : public QDialog, public Ui::About {
Q_OBJECT
public:
AboutDialog( QWidget * parent = 0);
};
AboutDialog.cpp:
AboutDialog::AboutDialog( QWidget * parent) : QDialog(parent) {
setupUi(this);
// perform additional setup here ...
}
Usage:
#include "AboutDialog.h"
...
void MainWindow::on_actionAbout_triggered() {
about = new AboutDialog(this);
about->show();
}
In any case, the important code is to call the setupUi() method.
BTW: Your dialog in the code above is non-modal. To show a modal dialog, either set the windowModality flag of your dialog to Qt::ApplicationModal or use exec() instead of show().
For modal dialogs, you should use exec() method of QDialogs.
about = new QDialog(0, 0);
// The method does not return until user closes it.
about->exec();
// In this point, the dialog is closed.
Docs say:
The most common way to display a modal dialog is to call its exec() function. When the user closes the dialog, exec() will provide a useful return value.
Alternative way: You don't need a modal dialog. Let the dialog show modeless and connect its accepted() and rejected() signals to appropriate slots. Then you can put all your code in the accept slot instead of putting them right after show(). So, using this way, you wouldn't actually need a modal dialog.