Binary XML file line #6: You must supply a layout_width attribute. Works when layout_height="match_parent", but not "wrap_content"

Question

[EDIT] I simplified things and narrowed it down to just the toolbar and recycler

What I need:

An appcompact toolbar and a recyclerview.
The problem:

When the recyclerview OR toolbar's layout_height attribute is set to "wrap_content", it runs fine in AndroidStudio's preview, but when I compile it, it crashes and says

Binary XML file line #6: You must supply a layout_width attribute.

My question:

Why on earth would changing the layout_height to wrap content invalidate the layout_width?
Things I've tried:

Invalidating android studio's cashe, cleaning the build, and using RelativeLayout instead of LinearLayout. I've also tried making the layout_height attributes "match_parent", and it compiles... but the toolbar takes up the entire screen and the RecyclerView is pushed off.

The code:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical">
        <!-- Toolbar -->
        <android.support.v7.widget.Toolbar
            android:id="@+id/toolbar"
            android:layout_height="wrap_content"
            android:layout_width="match_parent"
            android:minHeight="?attr/actionBarSize"
            android:background="@color/red">

                <com.classtime.fragments.SpinnerCustom
                    android:id="@+id/spinner_nav"
                    android:spinnerMode="dropdown"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content" />
            </android.support.v7.widget.Toolbar>
        <!-- Recycler -->
        <android.support.v7.widget.RecyclerView
            android:id="@+id/todo_recycler"
            android:scrollbars="vertical"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"/>
    </LinearLayout>

denvercoder9 denvercoder9 · Accepted Answer · 2015-03-06T03:05:03

Try the following:

<LinearLayout      >

      <toolbar>

            <spinner.custom />

      </toolbar>

      <drawer>
            <recyclerview />

            <left listview/>

            <right listview/>
    </drawer>

</LinearLayout>

Binary XML file line #6: You must supply a layout_width attribute. Works when layout_height="match_parent", but not "wrap_content"

2 Answers