Question

When I use include in a layout, I have to set width and height both to include tag and to the layout it is linked to. Otherwards it won’t work correctly. So, it seems, that include is not a link, but a subclass of View, if it has its own width, height, id and so on. But on developer’s site there is not such class as include. Who are you, Mr. include?

Answer 1

The <include> tag can be thought of as a copy/paste of the internal layout. It’s part of the xml parsing that’s in the View Inflater classes. It effectively takes the layout ID, inflates the xml object you pass in, then adds it to the main layout that it’s inflating based on the attributes of the included layout. You can use it on anything that inherits from View.

You can overwrite any of the attributes that have layout_ in them. You don’t have to overwrite the width and height attributes if they are included in the root of the layout your including. However, you do have to overwrite those parameters if you are overwriting any other attribute. It’s part of a bug in how <include> is parsed. If you want to change, say, layout_marginLeft, you would have to overwrite layout_width and layout_height to the same values that are in the layout in order for the parser to overwrite the left margin attribute.