Those two custom directives have been created for the needs of the sample application. tkToggleNavButton
is custom Angular 2 directive, which allows reusing the same logic for the Navigation Back button, without the need to write the same code for every example. The same case is also for tkExampleHeader
which is responsible for setting up the correct title in the ActionBar. The definitions for those directives could be found here
Bear in mind that creating custom directives technic is related to Angular 2. Regarding that, there is nothing special on them and you could simply ignore them. In case you need to create your own custom directive you could review this article
in the Angular 2 documentation and the example here
Hope this helps.