Comments, Code and Qt. » Qt

Sunday evening fun: Windows Phone 7 styled progress indicator in QML

kypeli — Sun, 22 Jan 2012 22:05:22 +0000

I started a new coding hobby project today. But instead of actually getting very far with the productive part of the project I got side tracked on something fun I wanted to try out (don't you just love when that happens That's not possible when coding at work...). I wanted to share this day's outcome with you.

Technorati Tags: qml, Qt, qt quick, wp7. windows phone

Porting MeeGo Qt Components apps to Symbian

kypeli — Mon, 12 Dec 2011 06:09:47 +0000

Of course I don't have all the answers to what needs to be done for any given MeeGo Qt Component based application to have it running on Symbian, but I think I have three general actions that need to be done when porting an app from MeeGo to Symbian; have it run with the resources, make the code compile and tweak the UI.

Technorati Tags: porting, qml, Qt, qt components, qt quick, symbian

A MeeGo developer’s endeavors to the Symbian Qt world

kypeli — Tue, 06 Dec 2011 20:08:17 +0000

I've been working with Qt for a while already and we all know what a great cross-platform framework it is. When Nokia bought Trolltech in 2008 it was clear that Nokia wanted to make Symbian development easier. However, the QWidget based toolkit would not fly on Symbian, or any other mobile platform for that matter, so Nokia built some mobile UI frameworks on Qt (and oh boy Nokia is good at building frameworks for everything. Everyone should have at least one framework, if not two. I could write another blog post about that...). But while people in Europe were fighting over their frameworks, it was not until the guys and gals in Brisbane came up with QML when everything changed. Qt could finally be cross platform again and in an elegant way!

Technorati Tags: MeeGo, podcatcher, Qt, qt components, symbian

Easy threading with QtConcurrent::run()

kypeli — Sun, 18 Sep 2011 05:51:16 +0000

The following scenario is probably familiar to you: you are doing some heavy computing or IO intensive things in your app, like accessing a database, the filesystem or reading data from the Internet, that blocks your UI thread which leads to that the UI freezes. If you are writing a Qt app then probably the first thing that comes to your mind is to subclass QThread and implement the run() method (although you should not do that). But before you do that, you should take a look at Qt Concurrent and what it can offer. There is a good chance that what you need is already provided by the Qt Concurrent framework.

Technorati Tags: concurrent programming, mutex, Qt, qtconcurrent, threads

Why QNetworkAccessManager should not have the finished(QNetworkReply *) signal

kypeli — Sat, 30 Jul 2011 12:20:26 +0000

I was recently writing some network code in Qt using QNetworkAccessManager and again I did the mistake I've already done a few times. The reason for my mistake was that QNetworkAccessManager provides the finished(QNetworkReply *) signal.

Technorati Tags: c++, network programming, qnetworkaccessmanager, Qt

Sneak peek: Integrate your application with the Nokia N9 events view.

kypeli — Tue, 05 Jul 2011 20:20:24 +0000

I am working on a Qt C++ library that will integrate your application with the Nokia N9 MeeGo Harmattan event feed page. You can add and update items with your icon, text or even a list of images that will be shown on the event feed page. I still want to add some features and polish the code before publishing it, but the library will be open source.

Technorati Tags: c++, event page, harmattan, library, nokia n9, Qt

Deploying Qt and Qt Quick applications on Windows

kypeli — Sun, 03 Jul 2011 08:33:19 +0000

I recently had to deploy a Qt Quick application on a Windows machine that did not have Qt installed explicitly on it. I think this is a pretty common use case that can cause quite some headache. You basically have two options if you want to deploy (or install) your Qt or Qt Quick based application to Windows. Either you can use the Windows Installer service directly or use some free or commercial utility to create a MSI based installer application that will deploy your application on Windows. Alternatively or at least as a first step you can package your application into a ZIP, or some other, package together with the necessary libraries that the application depends on. This is what I did and what I am going to explain here. When the package is extracted on the target machine, your Qt or Qt Quick application can be run from that directory just by launching the .exe file. Pretty neat.

Technorati Tags: deployment, Qt, qt quick, windows

What is the developer story for the Nokia N9?

kypeli — Sun, 26 Jun 2011 08:52:46 +0000

The MeeGo Harmattan powered Nokia N9 has now been out for a couple of days. Nokia's developer pages has a whole section dedicated to the Nokia N9 and we also have some great UX guidelines available. But as an app developer I am really just interested in writing my code and deploying it on to the device or the emulator. I already wrote earlier that the "official" developer story around Qt SDK 1.1.2 did not work for me and I am still wondering if this approach will work really well in Windows and OS X.

Technorati Tags: development, harmattan, nokia n9, Qt, qt components, qt quick

How to set up MeeGo Harmattan development environment in Linux

kypeli — Sat, 25 Jun 2011 12:07:55 +0000

Nokia N9 and MeeGo Harmattan are here. These are good times to be a Qt developer. And if you are like me, you downloaded the Qt SDK 1.1.2 from Nokia that contains the experimental Harmattan target for Qt Creator. However, not sure about you, but I never got the QEMU to work which I though would be a part of the Qt SDK 1.1.2. Whenever I launch a Qt application with the Harmattan as the selected target, I get an error saying that QEMU was not running, so I assume it's not included or Qt Creator cannot find it. Or then I just don't understand how to set it up in Qt Creator... There's even a page at developer.nokia.com that explains how to use and install the QEMU on a Linux Debian based machine, but the download link to QEMU is broken (25.6.2011). Also it seems that it's a bit open what the deal with QEMU on Windows or OS X based machine are... I haven't seen similar pages for downloading QEMU for other than Linux. So at this point I am not sure if and how the QEMU should work together with Qt Creator. I forgot about the QEMU option then.

Technorati Tags: development, harmattan, nokia n9, Qt, scratchbox

OAuth2 explained with Qt Quick

kypeli — Sat, 21 May 2011 07:59:30 +0000

...or how to do Facebook authentication with Qt Quick.

In this blog post I will give you an idea how OAuth2 works and how to gain access to Facebook from your Qt Quick application using OAuth2. I could have used any other service that uses OAuth2 for this blog post too, but I chose Facebook since it is a fairly well known and widely used service.

Technorati Tags: authentication, facebook, oauth2, Qt, qt quick