Send signals to MainWindow from another window

[Peter_Dev]

Hi, everyone!
I created second dialogue window from my MainWindow by

SecondWindow *SW = new SecondWindow();
SW->show();

SecondWindow contains 6 QPushButtons inside. I'd like to be able to send 6 different clicked()signals from SecondWindow to MainWindow, so that each button has it's own signal. I guess, the best to do this is by connect(), but i still can't figure out how to implement it in code.

[Lemat]

on the secondWindow, create signal in header for each button. then when you will clicked on a button, the on_clicked slot you implemented from ui for each button would emits the specific signal.
Like this:

SecondWindow.h :

signals:
 Void button0 ();
 Void button1 ();
 //same for 4 remaining buttons

SecondWindow.cpp : (after create slots from ui)

Void on_button0_clicked ()
{
emit button0();
}
//repeat for 5 others buttons

MainWindow cpp:

SecondWindow *SW = new SecondWindow();
connect (SW, SIGNAL (button0()), this, SLOT(desired_slot ()));
//repeat for 5 others signals
SW->show();

Test it!!!!

[qt.1234]

do the connection in your MainWindow.
declare signal clicked() in your SecondWindow.h
and declare slot buttonClickSlot() in your MainWindow.cpp and MainWindow.h
QObject::connect(SW, SIGNAL(clicked()), this, SLOT(buttonClickSlot()), Qt::AutoConnection);

[Peter_Dev]

Should i somehow connect to buttons? I followed your instructions but, unfortunately, when i press any of buttons, i get no response.

[Lemat]

You have theses buttons on ui or declared in QMainWindow cpp?

[Peter_Dev]

@Lemat , I created these buttons on ui of SecondWindow and i want to connect their signals (if they were clicked) to slots in MainWindow

[Lemat]

From my knowledge, declare the specifics slots in MainWindow as public, and instantiate MainWindow in SecondWindow. After try this:

connect (this->qpushbutton, SIGNAL(clicked  (bool)), MainWindow, SLOT(specific_slot (bool)), Qt::DirectConnection);

this refer to SecondWindow

Hope it will work for you, test it!!!!

[Peter_Dev]

@Lemat , how can i get MainWindow in connect (this->qpushbutton, SIGNAL(clicked (bool)), MainWindow, SLOT(specific_slot (bool)), Qt::DirectConnection);?
if i use

MainWindow *win = new MainWindoow();

i guess there's a endless cycle creates because i open a SecondWindow from MainWindow and i don't see any window. Program just uses my processor.

[Lemat]

Wow, my apologies!!!, i have not pay attention...

[Lemat]

on the secondWindow, create signal in header for each button. then when you will clicked on a button, the on_clicked slot you implemented from ui for each button would emits the specific signal.
Like this:

SecondWindow.h :

signals:
 Void button0 ();
 Void button1 ();
 //same for 4 remaining buttons

SecondWindow.cpp : (after create slots from ui)

Void on_button0_clicked ()
{
emit button0();
}
//repeat for 5 others buttons

MainWindow cpp:

SecondWindow *SW = new SecondWindow();
connect (SW, SIGNAL (button0()), this, SLOT(desired_slot ()));
//repeat for 5 others signals
SW->show();

Test it!!!!

[Peter_Dev]

@Lemat , thanks a lot for your time. I followed your instructions, but still i don't receive a signal from SecondWindow, though i get no error message. Does your code work for you?

[jsulm]

@Peter_Dev Please post your code.
Did you make sure connect() succeeded (it returns a bool)?

[Lemat]

@Peter_Dev , hello please post your code...

[Peter_Dev]

@Lemat, my code is very mess. I'm trying to clean it now. I think i know where i made mistake..
Thanks a lot for your time. I tried your solution on another project and it works perfect!

[Lemat]

@Peter_Dev
Glad it worked for you. it's a solution I use very often. if everything is ok, pass this subject to resolved.