Clickable CardView inside NestedScroll doesn't

Question

I have a layout with a CoordinatorLayout, and AppBarLayout and a NestedScrollView, inside the NestedScrollView I have multiple CardViews, everything works ok until I set the CardViews to be clickable, then if I start a scroll within a CardView, scroll doesn't work.

This is my layout:

<android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="@+id/main_content"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true">
<android.support.design.widget.AppBarLayout
    android:id="@+id/appbar"
    android:layout_height="256dp"
    android:layout_width="match_parent"
    app:contentScrim="?attr/colorPrimary"
    android:fitsSystemWindows="true"
    app:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar">
    <android.support.design.widget.CollapsingToolbarLayout
        android:id="@+id/collapsing_toolbar"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:layout_scrollFlags="scroll|exitUntilCollapsed"
        android:fitsSystemWindows="true"
        app:contentScrim="?attr/colorPrimary">
        <ImageView
            android:id="@+id/backdrop"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:scaleType="centerCrop"
            android:fitsSystemWindows="true"
            app:layout_collapseMode="parallax"/>
        <android.support.v7.widget.Toolbar
            android:id="@+id/toolbar"
            android:layout_height="?attr/actionBarSize"
            android:layout_width="match_parent"
            app:layout_collapseMode="pin"
            app:popupTheme="@style/ThemeOverlay.AppCompat.Light" />
    </android.support.design.widget.CollapsingToolbarLayout>
</android.support.design.widget.AppBarLayout>
<android.support.v4.widget.NestedScrollView
    android:id="@+id/nestedScroll"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    app:layout_behavior="@string/appbar_scrolling_view_behavior"
    android:layout_gravity="fill_vertical">
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical">
        <android.support.v7.widget.CardView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            app:cardCornerRadius="0dp"
            app:cardUseCompatPadding="true">
            <LinearLayout
                android:orientation="horizontal"
                android:layout_width="match_parent"
                android:layout_height="wrap_content">
                <View
                    android:layout_width="80dp"
                    android:layout_height="80dp"
                    android:background="@color/primary" />
                <LinearLayout
                    android:orientation="vertical"
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:paddingTop="4dp"
                    android:paddingLeft="7dp"
                    android:paddingRight="7dp"
                    android:paddingBottom="7dp">
                    <TextView
                        android:layout_width="match_parent"
                        android:layout_height="wrap_content"
                        android:lines="1"
                        android:includeFontPadding="false"
                        android:text="Title1"
                        style="@android:style/TextAppearance.Medium" />
                    <TextView
                        android:lines="2"
                        android:text="Description 1"
                        android:layout_width="match_parent"
                        android:layout_height="wrap_content" />
                </LinearLayout>
            </LinearLayout>
        </android.support.v7.widget.CardView>
       ...
    </LinearLayout>
</android.support.v4.widget.NestedScrollView>

Answer 1

The issue comes to daylight when the ScrollView isn't filled with content. I think it's a very weird bug in Android.

The 'solution'..

<android.support.design.widget.CoordinatorLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/main_content"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:fitsSystemWindows="true"
    tools:context=".MainActivity">

    <android.support.design.widget.AppBarLayout
        android:id="@+id/appbar"
        android:layout_height="256dp"
        android:layout_width="match_parent"
        app:contentScrim="?attr/colorPrimary"
        android:fitsSystemWindows="true"
        app:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar">

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

            <ImageView
                android:id="@+id/backdrop"
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:scaleType="centerCrop"
                android:fitsSystemWindows="true"
                app:layout_collapseMode="parallax"/>

            <android.support.v7.widget.Toolbar
                android:id="@+id/toolbar"
                android:layout_height="?attr/actionBarSize"
                android:layout_width="match_parent"
                app:layout_collapseMode="pin"
                app:popupTheme="@style/ThemeOverlay.AppCompat.Light"/>
        </android.support.design.widget.CollapsingToolbarLayout>
    </android.support.design.widget.AppBarLayout>

    <android.support.v4.widget.NestedScrollView
        android:id="@+id/nestedScroll"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:layout_behavior="@string/appbar_scrolling_view_behavior"
        android:layout_gravity="fill_vertical">

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:orientation="vertical">

            <android.support.v7.widget.CardView
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                app:cardCornerRadius="0dp"
                app:cardUseCompatPadding="true"
                android:foreground="?android:attr/selectableItemBackground"
                android:clickable="true">

                <LinearLayout
                    android:orientation="horizontal"
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content">

                    <View
                        android:layout_width="80dp"
                        android:layout_height="80dp"
                        android:background="#cdcdcd"
                        android:clickable="true"/>

                    <LinearLayout
                        android:orientation="vertical"
                        android:layout_width="match_parent"
                        android:layout_height="wrap_content"
                        android:paddingTop="4dp"
                        android:paddingLeft="7dp"
                        android:paddingRight="7dp"
                        android:paddingBottom="7dp">

                        <TextView
                            android:layout_width="match_parent"
                            android:layout_height="wrap_content"
                            android:lines="1"
                            android:includeFontPadding="false"
                            android:text="Title1"
                            style="@android:style/TextAppearance.Medium"/>

                        <TextView
                            android:lines="2"
                            android:text="Description 1"
                            android:layout_width="match_parent"
                            android:layout_height="wrap_content"
                            />
                    </LinearLayout>
                </LinearLayout>
            </android.support.v7.widget.CardView>

            <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="1000dp"
            android:orientation="vertical"
            android:layout_margin="4dp"
            android:background="#c1c1c1">

            <TextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:textSize="20pt"
                android:text="some content..."/>
        </LinearLayout>

        </LinearLayout>
    </android.support.v4.widget.NestedScrollView>
</android.support.design.widget.CoordinatorLayout>

Answer 2

It seems like the same problem as here: Scroll doesn't work in NestedScrollView when try to scroll from views with click events

This is the kind of workaround for your problem https://stackoverflow.com/a/32887429/2165810

But you shuld also use setPreventCornerOverlap(false) for your CardView to avoid problems with CardView

Answer 3

As people have noted, the problem is when the CardView sits fully within the screen it won't trigger scrolling from the card. Scrolling still works from views within the CollapsingToolbarLayout.

My solution was to add android:layout_marginBottom="100dp" to the CardView so that the bottom edge is offscreen thus allowing scrolling.