You will need to have already installed the Software Development Kit before you do this. Currently, on May 29, 2012, the latest version of the Qt SDK is 1.2.1. You can get the installer here. For my installation I used the Linux 64 bit Offline Installer. This will also install QtCreator 2.3.1 as part of the whole package. Now, since they haven't (yet) released an SDK that includes QtCreator 2.5, you can just grab the binary here and install it yourself.
Download it, it should be about 98mb so it will depend on your connection speed how long it takes.
Open the folder where you downloaded it.
Right click on it. It should look like this: qt-creator-linux-x86_64-opensource-2.5.0.bin
Select the permissions tab.
Check the box for "Allow executing file as program."
Now I would just say, "Now double-click on it", but that didn't work for me. It gave me some error:
Could not display "/home/ultrajones/Downloads/q...x-x86_64-opensource-2.5.0.bin"
The file is of an unknown type
No it isn't.
So open a terminal and CD to the directory where you downloaded it. Most likely this is the Downloads folder in your Home directory. When you open a terminal you will already be in the Home directory, so just type:
And you will be there.
You will see a list of all the files and folders in that directory.
Somewhere on the list you should see:
Here's a nice trick. Now type:
and hit the tab key. The terminal should fill out the rest of the name for you, since it is the only thing in the folder with a name starting with "qt-". Oooh magic. By the way, the dot ( . ) stands for current directory and the slash ( / ) just tells the terminal to execute the following file. Now just hit enter and the installer should fire up.
If it didn't, don't blame me. I do this for free!