Modifying nested attributes on an included Layout

Question

I've been learning about merge and include lately, and I have a question I can't seem to figure out the answer too. Say I have a layout that defines a header component that I want to add to multiple layouts. However, I want to change the title, or icon of each header per each include usage. For example say I have the following layout:

<RelativeLayout android:layout_width="fill_parent"
                android:layout_height="wrap_content"
                style="@style/menu_header">

    <Button android:id="@+id/backButton"
            android:layout_alignParentLeft="true"
            android:layout_centerVertical="true"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            style="@style/button"
            android:text="@string/back"/>

    <TextView style="@style/headerTitle"
              android:layout_centerInParent="true"
              android:text="${title}"
              android:layout_height="wrap_content"
              android:layout_width="wrap_content"/>
</RelativeLayout>

Then I can include that in other layouts using:

<LinearLayout ...>
   <include android:id="@+id/searchHeader" layout="@layout/shared_header" title="Search"/>
   ...
</LinearLayout>

I know I can modify any layout_* attribute of the root element, but can I define other attributes that get substituted into the layout, like say "title" in this example, without having to create my own subclass of View, add declare-styleable definitions in valaues/resources, etc?

Having something like this would make creating reusable views so much simpler, but I can't seem to find any evidence that says if merge + include can do it.

Blare

I kind of think that if you want to change the contents of those views, you should be using a custom View made up of those views. The include thing is more a facility for when you want to copy/paste a view/viewgroup elsewhere. – Ligulate

But include is of limited use if you can only copy and paste exactly the same code. Custom views require a lot more overhead to author, adding custom style options, creating code to subclass a view, etc. If all I'm doing is tweaking some attributes of nested elements it seems like that could be done without eating the whole elephant – Blare

I read the quick "tutorial" on include again ( android-developers.blogspot.com/2009/02/… ), and it seems pretty clear that it's just meant to be a simple copy/paste, especially when you include a common "sub-layout" in 2 different layouts (portrait and landscape). Though I do find your idea pretty cool after all :/ – Ligulate

Answer 1

The answer is nope. Unfortunately, Android isn't that powerful. You have to create your own extension of ViewGroup and write more code.

Blare

can you provide an example of how to do this? – Fluxion

No because writing your own custom component would take more effort and space than is allowed in a comment. You can't do what I describe using layout files alone. You have to write your own customer component by extending ViewGroup if you want to build something that can be reused and parameterized like this. – Blare

@Blare hey i have similar situation as yours. did you manage to create your custom viewgroup? if yes, can you shed some light here how did you do that? – Schram