When you are working in DITA, there are two approaches that you can use to create topics and maps. You can start by creating topics first, and then assemble your finished topics into one or more documents by creating one or more maps, or you can start by creating a map and then adding new topics to it as you work.
The topics-first approach is generally more appropriate if you are intending to do a lot of content reuse, as it encourages you to think of each topic as an independent unit that can be combined with other topics in various ways. The map-first approach will be more familiar to you if you are used to creating books or manuals as a whole. Oxygen XML Editor supports both approaches.
A DITA map organizes content hierarchically, so you can add a topic as a child of the map root or of any item already in the map. Therefore, the first step to adding a topic to a map is always to choose the place it will be inserted into the map.
At the XML-level, a topic is added to a map by adding a reference to the map that points to the topic. There are a number of different reference types that you can use. The default is the topicref element. See the DITA documentation for the full range of reference elements and their uses. Oxygen XML Editor provides several different tools for inserting reference elements into a map:
Insert Reference
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Insert Reference... from the DITA Maps
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