How to open another form in Qt4?

[sapslaj]

Hello there! I am new to the forum, so just bear with me...

I am trying to open another form by clicking a button on the first form. I tried...

form1 w;
w.show();

form1 w;
w.show();

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And it shows form2 then immediately closes form2.

form1 w;
w->show();

form1 w;
w->show();

To copy to clipboard, switch view to plain text mode 

Gives compiler error: "form1.cpp:84: error: base operand of '->' has non-pointer type 'form2'"

static Form2 *form2 = new Form2(this);
form2->show();
form2->activateWindow();
form2->raise();

static Form2 *form2 = new Form2(this);
form2->show();
form2->activateWindow();
form2->raise();

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gives compiler error: "form1.h:21: error: ISO C++ forbids declaration of 'Form2' with no type."
and error: "C:\Users\sapslaj\Desktop\chat-build-desktop\..\chat\mainlogin.h:21: error: expected ';' before '*' token"

I have tried everything I know possible, and I cannot get it to stay open. Any help?

[wysota]

http://www.qtcentre.org/faq.php?faq=...esigner_2forms

[ChrisW67]

I am trying to open another form by clicking a button on the first form. I tried...

form1 w;
w.show();

form1 w;
w.show();

To copy to clipboard, switch view to plain text mode 

And it shows form2 then immediately closes form2.

What is the lifetime of the stack-allocated w object in C++? This is basic C++, not a Qt question.
Given that w.show() is non-blocking, why do you think the window might go away?

form1 w;
w->show();

form1 w;
w->show();

To copy to clipboard, switch view to plain text mode 

Gives compiler error: "form1.cpp:84: error: base operand of '->' has non-pointer type 'form2'"

What do you think the error message is telling you? This is basic C++, not a Qt question. You might find some clues in your next snippet.

static Form2 *form2 = new Form2(this);
form2->show();
form2->activateWindow();
form2->raise();

static Form2 *form2 = new Form2(this);
form2->show();
form2->activateWindow();
form2->raise();

To copy to clipboard, switch view to plain text mode 

gives compiler error: "form1.h:21: error: ISO C++ forbids declaration of 'Form2' with no type."
and error: "C:\Users\sapslaj\Desktop\chat-build-desktop\..\chat\mainlogin.h:21: error: expected ';' before '*' token"

Where is the class Form2 declared? This is basic C++, not a Qt question.

You may have noticed a theme in my questions. You have all the elements of the Qt side of this problem here and in the FAQ page wysota gave you but your C++ knowledge is letting you down.