How to hide AppBarLayout programmatically in android?

Question

Java

(Corrected code!) Hello people, tell me how to hide the AppBar or what is the correct name? (ActionBar) in general, it doesn't matter! In my project there is such an AppBarLayout, I try to hide it programmatically, but my code does not work out

if (bla bla bla){
                    AppBarLayout AppBarLayout = findViewById(R.id.appbar_layout);
                    AppBarLayout .setVisibility(View.GONE);
}else{
   AppBarLayout .setVisibility(View.VISABLE);
}

It leaves behind a white background, and if you pass android:visibility="gone" to the layout, it is completely removed. Question: how to remove this white background?

Or how is it properly hidden so that it does not leave behind a white background? And the layout stretched to full height!

Answer 1

Find the view that occupies this space and hide it in the same way as you do it now. This is probably the parent of the toolbar. You can see it with the Layout inspector.

Answer 2

getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,WindowManager.LayoutParams.FLAG_FULLSCREEN);

Create activity in onCreate

Answer 3

Is it generally possible to assign absolute positioning to AppBar?