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The Book of Qt 4 – a short review
Posted by JLP on August 22nd, 2007
Alternative operating systems like Linux and Mac OS are getting more and more popular these days. That’s why cross platform technologies and programming are also increasingly popular and important. One of such technologies is a C++ GUI programming library and framework called Qt. Today I’ve just finished reading a book about it, The Book of Qt 4 – The Art of Building Qt Applications. This is my short review of it.
The author of the book is Daniel Molkentin, who is one of the main developers at the KDE project. KDE is an entire desktop environment based on Qt. On more than 400 pages Daniel did a great job of presenting basic concepts and components behind Qt 4. Compared to another Qt book I’ve got, C++ GUI Programming with Qt 4, the introduction to Qt in this book is more smooth and friendlier to readers who are just starting to learn Qt. Examples are simpler and there is a separate example for every topic. So you don’t need to complete something from the beginning of the book to try another thing from the end. It is also nice that there are step by step instructions on how to use Qt’s graphical tool to design the main application window and dialogs. With 48 and 44 pages two of the longest chapters describe model/view programming using Interview framework and Qt’s powerful painting system called Arthur. Like the rest of the chapters these two are also presented in a way that doesn’t overload the reader with too much information. For complete list of topics covered check out the table of contents.
At the end I can say that this is a great book for anyone getting started with Qt 4 programming. By learning Qt 4 you will be able to reach more users, program faster and enjoy more while doing it. Not to mention you will be ready to start developing for KDE 4, which will be released in a few months and is destined to be one of the most exciting desktop environments ever.
July 16th, 2008 at 03:37:24
Its a great book but i cant seem to find a place anywhere that describes painting image data line by line. The rotateRgb example in the “The book of qt4″ is the closest thing i could find. Ive been looking everywhere for an example of how to read bitmap data via a bytestream and paint this on a QScene. Do you now any good places to look for this?
August 21st, 2008 at 19:44:13
I’m learning to use Qt4 and use this book as reference.
On the chapter 2 there are a sample code about “Byte Converter”. There are 3 lineEdit widget (editDec, editHex and editBin) which interact each other through signal slot.
I have follow the instruction step by step, but I have stumble on 2 problems , i.e:
1. after 2 or there input, the linedit won’t update i.e it just goes blank.
2. update made to editHex give wrong result: it treat the input as decimal not hex,
e.g if I input “10″ to editHex the editDec is also “10″ not 16 as it should be.
Are these problem because I use different version of Qt? (I’m using Qt 4.4.0)
Anybody have the same experience?
PS:
After x-ref the Qt refmanual , I tweak the code :
1. in the convertion function I change the signal:
from
connect (decEdit,SIGNAL(textChanged)(const QString&)), ....to
connect (decEdit,SIGNAL(textEdited)(const QString&)), ....The problem maybe because (according to QT ref manual) “textChanged” also emitted signal
when the text is changed programmatically as it did in the sample code
2. in hexChanged and binChanged functions, I add the base number for toInt()function.
e.g from:
int num=newValue.toInt(&ok);to :
int num=newValue.toInt(&ok,16);are these the correct fixes? I’m still guessing.
thanks for any feedback.
regards Newbie