issue with “@id” vs “@+id” in positioning in Relative Layout

Question

Good day, i have a slight issue with relative layouts and i don\'t know why. Normally when you trying to position relative to other views, you use \"@id\" but it doesn\'t se

Answer 1

@+id is used when declaring the ID for the first time, and you should not use it in the positioning of elements. It should be used only for the android:id attribute.

@id on the other hand is used to reference an existing ID.

In a RelativeLayout, you cannot reference views below the referencing view in the current code. So if you have the following layout:

LayoutRoot
    View1
    View2
    View3

View1 cannot, or rather should not, use View2 and View3 to define its position. View2 should use only View1 to define its position, and View3 can use both View1 and View2.

Essentially, you can use @id whenever the view you're referencing through it has been declared above the referencing view in the layout file.

So simply switching the code blocks' position of your last two widgets should allow you to use @id: