Bdtjtk

So, I have an activity that contains a HorizontalScrollView. Here is a cleaned up xml.

<android.support.v4.widget.DrawerLayout

    style="@style/style_DrawerLayout">

<LinearLayout

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    android:orientation="vertical">

    <include

        layout="@layout/toolbar_std"/>

    <include

        layout="@layout/btn_bar_scroll"/>

    <android.support.v7.widget.RecyclerView

        android:layout_width="match_parent"

        android:layout_height="match_parent"/>

</LinearLayout>



<include

    layout="@layout/navigation_view"/>



</android.support.v4.widget.DrawerLayout>

And my btn_bar_scroll (only three button shown for clarity)

<HorizontalScrollView

    android:layout_width="wrap_content"

    android:layout_height="wrap_content"

    android:orientation="horizontal">

<LinearLayout

    android:layout_width="wrap_content"

    android:layout_height="match_parent"

    android:orientation"horizontal">

<Button

    android:layout_width="wrap_content"

    android:layout_height="match_parent"

    android:text="BTN1"

    android:drawableTop="@drawable/ic1"/>

<Button

    android:layout_width="wrap_content"

    android:layout_height="match_parent"

    android:text="BTN2"

    android:drawableTop="@drawable/ic2"/>

<Button

    android:layout_width="wrap_content"

    android:layout_height="match_parent"

    android:text="BTN3"

    android:drawableTop="@drawable/ic3"/>

</LinearLayout>

</HorizontalScrollView>

It works fine, exactly as expected. Except that when using Show GPU View Updates, I've noticed that every view on the entire page updates whenever the scroll is dragged either way (even the Toolbar updates). Not so great for performance.

Weirdly, by wrapping the HorizontalScrollView with another view, like with this FrameLayout, the unnecessary view updates stop (only the HorizontalScrollView updates when it is flicked). Any advice? I'd rather not have the extra FrameLayout for seemingly no reason.

<FrameLayout

android:layout_height="wrap_content"

android:layout_width="wrap_content">

<HorizontalScrollView

    android:layout_width="wrap_content"

    android:layout_height="wrap_content"

    android:orientation="horizontal">

<LinearLayout

    android:layout_width="wrap_content"

    android:layout_height="match_parent">

<Button

    android:layout_width="wrap_content"

    android:layout_height="match_parent"

    android:text="BTN1"

    android:drawableTop="@drawable/ic1"/>

<Button

    android:layout_width="wrap_content"

    android:layout_height="match_parent"

    android:text="BTN2"

    android:drawableTop="@drawable/ic2"/>

<Button

    android:layout_width="wrap_content"

    android:layout_height="match_parent"

    android:text="BTN3"

    android:drawableTop="@drawable/ic3"/>

</LinearLayout>

</HorizontalScrollView>

</FrameLayout>