41.4 Declaring a Navigation Host
For this project, the navigation host fragment will be contained within the user interface layout of the main activity. This means that the destination fragments within the navigation graph will appear in the content area of the main activity currently occupied by the main_fragment.xml layout. Locate the main activity layout file in the Project tool window (app -> res -> layout -> main_activity.xml) and load it into the layout editor tool.
With the layout editor in Design mode, drag a NavHostFragment element from the Containers section of the Palette and drop it onto the container area of the activity layout as indicated by the arrow in Figure 41-5:
From the resulting Navigation Graphs dialog, select the navigation_graph.xml file created in the previous section and click on the OK button.
With the newly added NavHostFragment instance selected in the layout, use the Attributes tool window to change the ID of the...
