Android Toolbar minHeight redundant?

Question

I built my Toolbar like in most with minHeight set to actionBarSize:

<android.support.v7.widget.Toolbar xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:background="@color/colorPrimary"
android:minHeight="?actionBarSize"
android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"
app:popupTheme="@style/ThemeOverlay.AppCompat.Light">
</android.support.v7.widget.Toolbar>

However, if I delete this attribute, there is no difference at all. The Toolbar keeps its actionBarSize, even if I remove the menu and set the app name to an empty String, so there is nothing displayed in the Toolbar at all.

Is there anything I'm missing here?

Answer 1

android:minHeight="?attr/actionBarSize"

minHeight will ensure that your toolbar does not resize itself lower than ?attr/actionBarSize not matter how small the content inside the toolbar is.

EDIT

If there is nothing inside a toolbar and if minHeight is not set, the toolbar will have a default height of 56dp which is equal to ?attr/actionBarSize

So setting minHeight for toolbar is redundant

For more details, What's the height of the Android Toolbar?