XML style rules - agileinfoways/Android-Guidelines GitHub Wiki

When an XML element doesn't have any contents, you must use self closing tags.

This is good:

<android.support.v7.widget.AppCompatTextView
	android:id="@+id/tv_profile"
	android:layout_width="wrap_content"
	android:layout_height="wrap_content" />

This is bad :

<!-- Don\'t do this! -->
<android.support.v7.widget.AppCompatTextView
    android:id="@+id/tv_profile"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content" >
</android.support.v7.widget.AppCompatTextView>

Resource IDs and names are written in lowercase_underscore.

IDs should be prefixed with the name of the element in lowercase underscore. For example:

Image view example:

<ImageView
    android:id="@+id/iv_profile"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content" />

Navigation Menu Item example:

<menu>
	<item
        android:id="@+id/nav_done"
        android:title="Done" />
</menu>

String names start with a prefix that identifies the section they belong to. For example registration_email_hint or registration_name_hint. If a string doesn't belong to any section, then you should follow the rules below:

Unless the rest of resources, style names are written in UpperCamelCase.

As a general rule you should try to group similar attributes together. A good way of ordering the most common attributes is:

1. View Id
2. Style
3. Layout width and layout height
4. Other layout attributes, sorted alphabetically
5. Remaining attributes, sorted alphabetically