NestedScrollView isn't scolling when start scrolling on ExpansionHeader (the scroll event isn't triggered)

[chlegou]

Hi,

i have a problem with Scrolling behavior of the activity when added 3 ExpansionPanels in vertical Linearlayout. since they are next to each others(in a row), they occupy a big space.

My activity is androidx.coordinatorlayout.widget.CoordinatorLayout with a androidx.core.widget.NestedScrollView
reference: https://developer.android.com/reference/com/google/android/material/appbar/AppBarLayout

The problem persist when start scrolling from the ExpansionHeader. It never scroll!

But it is scrolling when starting outside of the ExpansionPanel's Headers

By the way, i have an AppCompatAutoCompleteTextView in 2 ExpansionLayouts of the activity.

Each one of them is having a dropdown menu as described in the Material Guidelines:
link: https://material.io/develop/android/components/menu/#exposed-dropdown-menus

Here it is:

<com.google.android.material.textfield.TextInputLayout
	style="@style/Widget.MaterialComponents.TextInputLayout.OutlinedBox.Dense.ExposedDropdownMenu"
	android:layout_width="0sp"
	android:layout_height="wrap_content"
	android:layout_weight="1"
	app:boxStrokeWidth="2dp"
	android:hint="">

	<androidx.appcompat.widget.AppCompatAutoCompleteTextView
		android:id="@+id/exposed_dropdown"
		android:layout_width="match_parent"
		android:layout_height="wrap_content"
		android:editable="false"
		tools:ignore="Deprecated" />

</com.google.android.material.textfield.TextInputLayout>