[Qt-interest] New to QT - Beginners questions

[Bo Thorsen]

Den 01-09-2010 12:23, Jens Saathoff skrev:
>    Hi!
>
> I'm new to QT and want to discover it a bit. I've downloaded the version
> 4.6.3 with QtCreator for Windows.
> I'm not new to gui-stuff at all, so my questions in a list for short
> answers.
>
> 1. I'm using QTCreator with QTDesigner to design my windows. The
> generator generates an "ui_mainwindow.h" for example. In this header is
> a method "setupUI()" where all the sub-components are instantiated.
> So far so good. But how to use it? ui->mycomponent does not work at all.
> Must i create a new pointer in my mainwindoe-header and point it to
> ui->mycomponent in my mainwindow-constructor to call it in my other
> mainwindow's methods?
> Does QT remove the subcomponents from memory if the parentwindow was
> deleted? Or is it necessary to delete every subcomponent?

You need to read the designer manual:
http://doc.qt.nokia.com/4.6/designer-manual.html

Here you will see, that you have to create a widget as a container for 
the designer stuff.

Something like this:

QMainWindow* window = new QMainWIndow;
Ui::MainWIndow ui;
ui.setupUi(window);

In practice, I always subclass QMainWindow and call setupUi() from the 
constructor.

> 2. I've read about the SDK for mobile devices (Symbian, Maemo, Windows
> Mobile). Can i just create one code-base for all and compile it for each
> platform?

In theory, yes. However, I'd say that for anything non-trivial, you 
can't use the same GUI on all these. There is a *big* difference between 
running Qt on a small and on a big screen.

> That's all. Please excuse my stupid questions. I'm new to QT. I'll buy a
> book this week.

That's probably a good idea, but there is a lot of very good information 
in the documentation as well. Read it :)

Bo Thorsen,
Fionia Software.

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