is it possible to customize UI elements with a particular GUI framework?

I have only played around with GTK and I really did not spend too much time with it.. thus my question is what is a good cross platform GUI framework? and with one of those frameworks, is it possible to completely customize the design of the visual components? for instance what framework does Adobe use? or what framework does iTunes use, because those are some really clean looking UI's, and from what I've seen many of the cross platform apps don't look very good.

I very much appreciate any one who attempts to answer this question. It is a huge help. I am still in the beginning phases of my GUI based software career, and need all the help I can get.

The best gui framework I came across and which supports customization through a css style syntax would be Qt.

Also the documentation is very good, with excellent starter's tutorials, a big community and of course it's cross-platform.

Since GUIs are near and dear to my heart and I've dabbled with a number of GUI frameworks I'll do a bit of a write-up for you. Also, since this is tagged with C++ I'll assume you're working in C++.

**QT** (

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As already mentioned, QT is a very popular choice. If you're used to GTK (as you mentioned) it will be a bit foreign at first, but it's well documented and supported. The catch is that for a commercial license it'll cost you money. If you're just learning and working on your own at home or in an open source project, QT is entirely free.


**GTK+** (

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You already mentioned GTK. I recommend checking out GTK+.
It's pretty good and flexible, but the problem with GTK is you need to get your hands dirty. I'll also admit that using GTK your code can end up a bit on the ugly side, but if you have no money and want to make a commercial application check it out.


**Fast Light Toolkit (FLTK)** (

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We can all admit it, FLTK is a bit ugly. However, it has a cool GUI builder, is fully open source (so you can change whatever you want) and has a very fast, responsive and lean programming philosophy behind it. At least check it out.

There is an alternative one, free and open-source, called **Nana C++ Library** (

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), a pure C++ GUI library. The status of the library is active, and it is updated monthly. This is a new library, it would be a choice for your hobby project.