How to install the Qt SDK on the Ubuntu distribution of Linux

Qt's SDK ("Software Development Kit") is a cross-platform application framework that is widely used to develop applications with a graphical user interface (or "GUI" for " Graphical User Interface "in English). Among the applications developed with Qt, there are notably KDE, Opera, Google Earth and Skype. It is a cross-platform GUI application framework that is portable and works on Mac OS X, Lonux and Windows operating systems. Qt's SDK helps you create graphical user interfaces (or GUIs) for applications that can run on both Mac OS X, Linus, and Windows. For more information on the Qt SDK, see the Qt SDK website. For more information on how to create your first program with Qt, see this tutorial.

Remark:

this article details the installation of the 64-bit version of Qt SDK 4.8 and of Qt SDK 5.0, SDKs for the Ubuntu distribution of Linux, which will also work for Debian and Linux Mint.

Steps

Method 1 of 2: Qt SDK version 4.8 installation instructions

Step 1. To get started, look at which version (bitwise) of Ubuntu you are using, by opening a terminal and entering the command below

Then download the corresponding version of the Qt SDK for your operating system. For example, if you are on a 32-bit version of the Ubuntu distribution of Linux, download the 32-bit SDK from Qt. If you are on a 64-bit version of the Ubuntu distribution of Linux, download the 64-bit SDK from Qt.

Type or copy / paste:

file / sbin / init
Take note of the version (its number of bits) of the Ubuntu system architecture that will be displayed, either 32-bit or 64-bit.

Step 2. Then download the Qt SDK

Choose the version of Qt's SDK that matches the Ubuntu system architecture you have. You can also add software libraries, so that you can launch Qt applications without complications, by following the steps below.
Remark:

when you download the SDK, take the "offline" version because it takes less time to download, unless you have a very high speed connection.
There are two methods you can choose to download the Qt SDK: the online installer method and the offline installer method. It is often preferable to directly download the entire SDK via the offline method. As the classes in Qt's SDK are very heavy, it takes several hours to download the SDK with a slow connection. This may not be a problem for users just wanting to try Qt's SDK.
Suggestion:

it is strongly recommended to use the installer offline rather than online, unless you have a really fast connection.

Step 3. Open a terminal and enter the following commands there:

Type or copy / paste:

sudo apt-get install synaptic
Type or copy / paste:

sudo apt-get update
This command is used to update and synchronize the index files of packages from their sources on the Internet.
Type or copy / paste:

sudo apt-get install qt4-dev-tools libqt4-dev libqt4-core libqt4-gui
This command adds additional software libraries to your machine, allowing you to run Qt programs cleanly on your computer.

Step 4. Type or copy / paste:

cd / home /"Your username"/ Downloads

This will take you to the Downloads (or Downloads) folder on your system

Step 5. Type or copy / paste:

sudo -s chmod u + x QtSdk-offline-linux-x86_64-v1.2.1.run

This will make the Qt SDK executable by all users of the machine

Step 6. To install the Qt SDK, enter the following command

Type or copy / paste:

sudo -s./QtSdk-offline-linux-x86_64-v1.2.1.run -style cleanlooks
You will need to have super user rights to be able to install the Qt SDK.

Step 7. You will be asked to choose the folder where to install the Qt SDK

Choose / opt and the Qt SDK will be installed in a directory named / opt / QtSDK.

Step 8. Change the access permissions to the folder where the Qt SDK is located so that it is accessible to all users by entering the following command

Step 9. Type or copy / paste:

sudo -s chmod -R 777 / opt / QtSDK

This will make the Qt SDK executable by all users of the machine

Step 10. Type or copy / paste:

sudo -s chmod -R 777 / home /"Your username"/.config/Nokia

This will prevent the display of error messages when launching QCreator, saying that the software cannot write to the / home / folder."Your username"/.config/Nokia.

Step 11. Once the Qt software is installed, open a command terminal and use a text editor like gedit or nano to edit the / etc / profile file

Type or copy / paste:

sudo -s nano / etc / profile
Where
Type or copy / paste:

sudo -s gedit / etc / profile

Step 12. Scroll down to the bottom of the / etc / profile file and type the text below

This line must be added to the / etc / profile system file in order to have the option of compiling Qt programs from the terminal.

Step 13. Type or copy / paste:

PATH = / opt / QtSDK / Desktop / Qt /4.8.1/ gcc / bin: $ PATH
export PATH

Step 14. The bolded number above indicates the version number of Qt's SDK, so be sure to put the version number that matches the SDK you are installing

Qt's SDK is constantly improving with new versions. So double check your version number.

For example, we use the version 4.8.1 of Qt in our case, the version number indicated in / etc / profile should therefore be 4.8.1.

Step 15. Save the / etc / profile file and close it

Step 16. Reload the / etc / profile file using the following command

Type or copy / paste:

. / etc / profile
Make sure you put a period followed by a space in order to reload the / etc / profile file.

Step 17. Once the / etc / profile file has been modified, enter the following command to ensure that your system recognizes the Qt SDK correctly by having included it in the PATH

Step 18. Type or copy / paste:

which qmake

You should receive a response like the one below.
/opt/QtSDK/Desktop/Qt/4.8.1/gcc/bin/qmake

Step 19. Also enter the command below

Type or copy / paste:

qmake -version

Step 20. You should receive a response like the one below

QMake version 2.01a
Using Qt version 4.8.1 in /opt/QtSDK/Desktop/Qt/4.8.1/gcc/lib

Step 21. This tells you that you can now compile Qt programs from the command line

You are now ready to compile Qt programs on your Ubuntu machine. Once the Qt SDK is properly installed on your computer, you will want to start compiling your first Qt programs. Check out this tutorial for more information.