android: how to add a button with text inside collapsing toolbar
You can add button and image like this
<android.support.design.widget.AppBarLayout
android:id="@+id/appBarLayout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:fitsSystemWindows="true">
<android.support.design.widget.CollapsingToolbarLayout
android:id="@+id/collapsing_toolbar"
android:layout_width="match_parent"
android:layout_height="150dip"
android:fitsSystemWindows="true"
app:contentScrim="?attr/colorPrimary"
app:expandedTitleMarginBottom="20dp"
app:expandedTitleMarginEnd="64dp"
app:expandedTitleMarginStart="48dp"
app:layout_scrollFlags="scroll|exitUntilCollapsed">
<ImageView
android:id="@+id/header"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_collapseMode="parallax" />
<android.support.v7.widget.Toolbar
android:id="@+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
app:layout_collapseMode="pin"
app:popupTheme="@style/ThemeOverlay.AppCompat.Light" />
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="bottom|end"
app:layout_collapseMode="parallax"
android:orientation="horizontal">
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Button"/>
</LinearLayout>
</android.support.design.widget.CollapsingToolbarLayout>
</android.support.design.widget.AppBarLayout>
in your main scrollable content put this code
<android.support.v4.widget.NestedScrollView
android:id="@+id/scroll"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:clipToPadding="false"
app:layout_behavior="@string/appbar_scrolling_view_behavior">
</android.support.v4.widget.NestedScrollView>