CollapsingToolbarLayout ImageView Is Not Scrollable

Using cheesesquare - android support library example is it possible to make the Header ImageView scroll-able? ViewOffsetBehavior or AppBarLayout.Behavior, meaning that the touch is left unhandled - which is why it does nothing.

A possible workaround for third-party developers would be to extend AppBarLayout.Behavior and implement onInterceptTouchEvent() and onTouchEvent() and manipulate the app bar accordingly.

Videos

These show the current and intended behavior. These are also from the bug report.

• https://youtu.be/xWadOVEaTSY
• https://youtu.be/J8ITp6RusZo

Solution 2:

I found a workaround by embedding the imageView in a NestedScrollView:

  <android.support.design.widget.AppBarLayout
    android:layout_height="wrap_content"
    android:id="@+id/appbar"
    android:background="@color/transparent"
    android:layout_width="match_parent">
    <android.support.design.widget.CollapsingToolbarLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:background="@color/transparent"
        app:toolbarId="@+id/toolbar"
        app:layout_scrollFlags="scroll|exitUntilCollapsed">
        <android.support.v4.widget.NestedScrollView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            app:layout_collapseMode="parallax"
            app:layout_scrollFlags="scroll"
             app:layout_behavior="@string/appbar_scrolling_view_behavior">
            <ImageView
                tools:ignore="UnusedAttribute"
                tools:src="@drawable/placeholder"
                android:id="@+id/imageView"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:layout_gravity="center_horizontal"
                android:adjustViewBounds="true"
                android:scaleType="centerCrop"
                android:minHeight="200dp"/>
        </android.support.v4.widget.NestedScrollView>
        <android.support.v7.widget.Toolbar
            android:layout_height="?attr/actionBarSize"
            android:id="@+id/toolbar"
            android:elevation="0dp"
            android:layout_width="match_parent"
            app:layout_collapseMode="pin"/>
    </android.support.design.widget.CollapsingToolbarLayout>
</android.support.design.widget.AppBarLayout>

But I haven't tested it in prod as I met another issue with the fling to top gesture which is interrupted when the recyclerview reaches the top ( as explained in the bug report).

Solution 3:

From testing this on support library 23.1.1, this issue seems to have been fixed.

compile 'com.android.support:design:23.1.1'

You can now put into your CollapsingToolbarLayout anything, ImageView, RelativeLayout, TextView and it will scroll as intended.