Container in CoordinatorLayout with CollapsingToolbarLayout larger than the system window

Question

How do I prevent Framelayout container from expanding past the system window. As you can see below in the image, the framelayout is expanding past the system window. This is preventing the FloatingActionButton in the fragment to be cut off. I am not looking to put the Fab inside of the activity because of shared transitions between changing fragments.

View

<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto">

    <android.support.design.widget.CoordinatorLayout
        android:id="@+id/parent"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:background="@color/colorBackground"
        android:fitsSystemWindows="true">

        <android.support.design.widget.AppBarLayout
            android:id="@+id/app_bar"
            android:layout_width="match_parent"
            android:layout_height="160dp"
            android:background="@color/colorBackground"
            android:fitsSystemWindows="true"
            android:theme="@style/AppTheme.AppBarOverlay">

            <android.support.design.widget.CollapsingToolbarLayout
                android:id="@+id/toolbar_layout"
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:fitsSystemWindows="true"
                app:contentScrim="?attr/colorPrimary"
                app:expandedTitleMarginStart="64dp"
                app:layout_scrollFlags="scroll|exitUntilCollapsed"
                app:toolbarId="@+id/toolbar">

                <android.support.v7.widget.Toolbar
                    android:id="@+id/toolbar"
                    android:layout_width="match_parent"
                    android:layout_height="?attr/actionBarSize"
                    app:layout_collapseMode="pin"
                    app:navigationIcon="@drawable/ic_arrow_back"
                    app:popupTheme="@style/AppTheme.PopupOverlay" />

            </android.support.design.widget.CollapsingToolbarLayout>
        </android.support.design.widget.AppBarLayout>

        <FrameLayout
            android:id="@+id/container"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            app:layout_behavior="@string/appbar_scrolling_view_behavior" />

    </android.support.design.widget.CoordinatorLayout>
</layout>

---

Update Working Solution

public class MainActivity extends AppCompatActivity {
    ActivityAddPlanBinding binding;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        binding = DataBindingUtil.setContentView(this, R.layout.activity_add_plan);
        setSupportActionBar(binding.toolbar);
        initContainerHeights();
    }

    int appBarHeight;
    int screenHeight;

    private void initContainerHeights() {
        appBarHeight = binding.appBar.getLayoutParams().height;
        screenHeight = screenHeight();
        binding.appBar.addOnOffsetChangedListener(new AppBarLayout.OnOffsetChangedListener() {
            @Override
            public void onOffsetChanged(AppBarLayout appBarLayout, int verticalOffset) {
                binding.container.requestLayout();
                binding.container.getLayoutParams().height = screenHeight - (appBarHeight + verticalOffset);
            }
        });
    }

    private int screenHeight() {
        DisplayMetrics displayMetrics = new DisplayMetrics();
        getWindowManager().getDefaultDisplay().getMetrics(displayMetrics);
        return displayMetrics.heightPixels - statusBarHeight();
    }

    public int statusBarHeight() {
        final Resources resources = getResources();
        final int resourceId = resources.getIdentifier("status_bar_height", "dimen", "android");
        if (resourceId > 0) {
            return resources.getDimensionPixelSize(resourceId);
        } else {
            return (int) Math.ceil((Build.VERSION.SDK_INT >= Build.VERSION_CODES.M ? 24 : 25) * resources.getDisplayMetrics().density);
        }
    }
}

Answer 1

I have found a solution by calculating the screen height - the verticalOffset of the appbar.

Sulution

public class MainActivity extends AppCompatActivity {
    ActivityAddPlanBinding binding;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        binding = DataBindingUtil.setContentView(this, R.layout.activity_add_plan);
        setSupportActionBar(binding.toolbar);
        initContainerHeights();
    }

    int appBarHeight;
    int screenHeight;

    private void initContainerHeights() {
        appBarHeight = binding.appBar.getLayoutParams().height;
        screenHeight = screenHeight();
        binding.appBar.addOnOffsetChangedListener(new AppBarLayout.OnOffsetChangedListener() {
            @Override
            public void onOffsetChanged(AppBarLayout appBarLayout, int verticalOffset) {
                binding.container.requestLayout();
                binding.container.getLayoutParams().height = screenHeight - (appBarHeight + verticalOffset);
            }
        });
    }

    private int screenHeight() {
        DisplayMetrics displayMetrics = new DisplayMetrics();
        getWindowManager().getDefaultDisplay().getMetrics(displayMetrics);
        return displayMetrics.heightPixels - statusBarHeight();
    }

    public int statusBarHeight() {
        final Resources resources = getResources();
        final int resourceId = resources.getIdentifier("status_bar_height", "dimen", "android");
        if (resourceId > 0) {
            return resources.getDimensionPixelSize(resourceId);
        } else {
            return (int) Math.ceil((Build.VERSION.SDK_INT >= Build.VERSION_CODES.M ? 24 : 25) * resources.getDisplayMetrics().density);
        }
    }
}

Answer 2

remove "@string/appbar_scrolling_view_behavior" in framelayout..collapsing toolbar is designed for that purpose...else there is no need of colapsing toolbar..Its a waste to take collapsing toolbar if u dont want ur framelayout to be scrollable..