how do I install a new KDE theme?

I have been trying out KDE in Ubuntu 12.04 recently, and have downloaded a few themes from KDE-LOOK.ORG but I have no idea how to change the theme?

I can select a theme from the inbuilt repo from the settings, but how do I apply a theme that I have downloaded from the KDE-LOOK site (This for example http://kde-look.org/content/show.php/Amakage?content=150285), any clues?

Thanks

Solution 1:

Go to System settings -> Application appearance (or Workspace appearance).

In some items (Colors, Icons, etc) you have the option to:

• Get new (you can search in a dialog box)
• Import (search a downloaded file and install it)

In other items (Style):

• If it's in the repositories: use synaptics (or similar)
• If it isn't in ther repositories: see if there's a PPA and use it

There are other situations that involve compiling a theme, but that's a longer story.

Solution 2:

in xubuntu 18.04 and Qt5 you should

sudo apt install qt5ct qt5-style-plugins

and add in your .bashrc

export QT_QPA_PLATFORMTHEME=qt5ct

then run qt5rc and change the theme