Appcompat Toolbar Not Showing With Navigation Drawer

Question

I am trying to configure the following in my app:

• Toolbar (Appcompat v7 version)
• Navigation Drawer
• Pre-Lollipop Appcompat v7 Materia

Answer 1

DrawerLayout extends FrameLayout, but you are treating it like a LinearLayout. You can either wrap your tag and the following LinearLayout in another LinearLayout, or you can move your tag.

Also, "fill_parent" is deprecated and maps to "match_parent" so you should just use the latter. You can also remove the additional xmlns attributes in your LinearLayout element.

<android.support.v4.widget.DrawerLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/drawer_layout"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <LinearLayout
        android:id="@+id/layout_main"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical">

            <!-- Toolbar -->
            <include layout="@layout/toolbar"/>
            ...

Your original layout did not work because the Toolbar was hidden (z-ordered) behind the LinearLayout.