Ubuntu Software application installation
The Ubuntu Software application has a Graphical User Interface to let you search for programs and give you some information about them, but when you click the 'install' button it is basically running the command
sudo apt-get install packagename
As Mark Kirby & JonasCz have already stated, installing from the Ubuntu Software application or typing the
sudo apt-get install command are just two different ways of doing the same thing.
One advantage of the GUI method is that it will place a launcher icon of your newly installed program into the Unity launcher for you.
If you use the
sudo apt-get install command, and then want the Launcher icon for the program in the Unity Launcher, you need to search for the program with the Dash and then drag it onto the Launcher yourself.
In this case, it would appear that TexMaker and 'texlive-full' are different programs and would have different Launcher icons, so the TexMaker icon from your first Ubuntu Software installation of the program will continue to launch TexMaker and will not have been replaced by 'texlive-full'.
[Incidentally, it's possible that the program TeXstudio (found in Ubuntu Software) may have the functionality that you are after]
Upon further investigation (I'm unfamiliar with TexMaker & 'texlive-full') it seems that 'texlive-full' is described as 'TeX Live: metapackage pulling in all components of TeX Live'. Whether this means it installs a separate program called 'Tex Live' or is supposed to add some functionality to TexMaker is unclear to me. There is no mention of 'TexMaker' in the Texlive package information: http://packages.ubuntu.com/xenial/texlive-full
Further Edit: Nick Weimberg has a much clearer explanation in the comments: "TexMaker is a GUI program for writing LaTeX. TexLive is a collection of LaTeX packages that don't include a GUI, but are required for much LaTeX functionality. They are separate software programs and separate packages" - A program that doesn't have a GUI will not always have a Launcher, in which case you would run the program from the Terminal - a command such as
programname --help or
man programname should inform you of how to use it
Getting the Launcher Icon after a
sudo apt-get install command
Open the Unity Dash by clicking the Ubuntu Icon at the top of the Launcher or by pressing the 'Super' key.
The 'Super' key is the 'Windows' key on most PC's or the 'Command' key on a Mac.
If you type the name of the program you just installed into the dash ('tex' should be close enough for it to find it) it should show an icon that you can select to launch the program right there and then. You can also drag the icon onto the Launcher to keep it in the Launcher for easy access.
If you can't find your program by typing the name into the Dash, then at the bottom of the 'Dash page' are a couple of different icons: 'Home', 'Applications', 'Files', 'Videos', 'Music', 'Photos'.
Selecting 'Applications' will let you browse through all your installed applications and you should be able to find it there.
The quickest way to go straight to searching through your applications is to hold
A at the same time.