Hide AppBar when scrolling down

Question

I have an AppBar and a horizontal linearlayout (which includes an edit text and two imagebuttons) and other things in my layout. When user scrolls down,

Answer 1

In the Drawer.Layout add in android:fitsSystemWindows="true".

It's better to separate out your concerns. Using the sample provided by chrisbanes/cheesesquare, your layout would be better looking like this:

Replace this:

With

And then use the ViewPager to populate your list.

 ViewPager viewPager = (ViewPager) findViewById(R.id.viewpager);
    if (viewPager != null) {
        setupViewPager(viewPager);
    }

private void setupViewPager(ViewPager viewPager) {
    Adapter adapter = new Adapter(getSupportFragmentManager());
    adapter.addFragment(new CheeseListFragment(), "Category 1");
    adapter.addFragment(new CheeseListFragment(), "Category 2");
    adapter.addFragment(new CheeseListFragment(), "Category 3");
    viewPager.setAdapter(adapter);
}

Then you can format this CheeseListFragment to add your image views individually.

It's also unnecessary to keep declaring your schema:

xmlns:app="http://schemas.android.com/apk/res-auto"

This is an indicator that you are copying and pasting code and not understanding it.

You should also be using a nestedScrollView without the view, and linear layout above it. Mind you, it's not clear what you are trying to acheive with that.