Android Material Design - How to change background color of Toolbar after CollapsingToolbarLayout is collapsed

Question

After the user scrolls down the screen, the image in the CollapsingToolbarLayout disappears and is left with a toolbar with the back button, content title,

Answer 1

Just use CollapsingToolbarLayout XML attribute contentScrim to set Toolbar background color when it's in collapsed mode.

app:contentScrim="YOUR_TOOLBAR_COLOR"

Here is an Example:

Hope this will help~