Actionmode Bar doesn't cover whole titlebar

In my app I need to use the ActionMode.

I have followed several Guides and Tutorials (https://medium.com/asos-techblog/style-actionmode-on-android-5e613fa77c32, https://developer.android.com/guide/topics/ui/menus e.g.) on implementing my Contextual Action Menu but as you can see in this image:

https://i.stack.imgur.com/ag2Mp.jpg

There is part of the titleBar still visible on the bottom. My question is if there is anything i can do to change this behaviour.

I also tried to change the style of my ActionModeBar but when i change the styling it becomes invisible (only showing the icons) and the titlebar is completely visible.

I have not made any changes to the ActionMode except the menu that contains the buttons:

<menu xmlns:android="http://schemas.android.com/apk/res/android"
	  xmlns:app="http://schemas.android.com/apk/res-auto">
	<item android:id="@+id/stopCab"
		  android:title="Stop contextual action bar"
		  app:showAsAction="ifRoom"
		  android:icon="@drawable/ic_baseline_cancel_24"/>
	
	<item android:id="@+id/deleteCab"
		  android:title="Delete selected items"
		  app:showAsAction="ifRoom"
		  android:icon="@drawable/ic_delete_white_24dp"/>
</menu>

Initializing the ActionMode:

    private ActionMode.Callback actionModeCallback = new ActionMode.Callback() {

        @Override
        public boolean onCreateActionMode(ActionMode actionMode, Menu menu) {
            MenuInflater menuInflater = getMenuInflater();
            menuInflater.inflate(R.menu.contextual_action_bar_menu, menu);
            return true;
        }

        @Override
        public boolean onPrepareActionMode(ActionMode actionMode, Menu menu) {
            return false;
        }

        @Override
        public boolean onActionItemClicked(ActionMode actionMode, MenuItem menuItem) {
            switch (menuItem.getItemId()) {
                case R.id.deleteCab:
                    //TODO: do something
                    return true;
                case R.id.stopCab:
                    //TODO: do something
                    return true;
                default:
                    return false;
            }
        }

        @Override
        public void onDestroyActionMode(ActionMode actionMode) {
            FieldChooserActivity.this.actionMode = null;
        }
    };

And starting the ActionMode:

FieldChooserActivity.this.actionMode = startActionMode(FieldChooserActivity.this.actionModeCallback);

In my Style the AppTheme parent is Theme.AppCompat.Light.DarkActionBar
And each Activity has

android:theme="@style/AppTheme.NoActionBar">

in AndroidManifest.
Maybe this is the fault why i cant change the style without the ActionMode becoming invisible.

I hope someone can help me with this matter and thanks in advance!

I found a solution that fixed my problem (where the ActionMode bar doesn't cover the Toolbar).

As i looked at the layout of my activity i saw that in the Toolbar is a height attribute called '?attr/actionBarSize':

<androidx.appcompat.widget.Toolbar 
	android:id="@+id/fieldChooserToolbar"
	android:layout_width="match_parent"
	android:layout_height="?attr/actionBarSize"
	android:background="?attr/colorPrimary"
	app:popupTheme="@style/AppTheme.PopupOverlay">

I then added the height to a custom style for my ActionMode:

<style name="ActionModeTheme" parent="AppTheme">
	<item name="windowActionModeOverlay">true</item>
	<item name="actionModeCloseDrawable">@drawable/ic_delete_white_24dp</item>
	<item name="actionMenuTextColor">@android:color/white</item>
	<item name="height">?attr/actionBarSize</item>
	<item name="background">@color/colorSecondary</item>
	<item name="android:src">@drawable/ic_baseline_close_24</item>
</style>

The last part was that i added following line to my AppTheme-styling:

<item name="actionModeStyle">@style/ActionModeTheme</item>

And then it worked!

The second problem where my ActionMode bar was invisible was most likely caused by adding the actionModeStyling to the AppTheme.NoActionBar.