Remove overlay view for better performance
Overlay view does not help performance, when animating
background color, invalidate() will be called on overlay View.
That's equivalent to invalidate() on ShadowOverlayContainer.
Remove the extra view to save memory and override draw()
instead. This turns out to save about 5~10% in UI thread and
RenderThread in a vertical scrolling of BrowseFragment
according to systrace.
Refactoring a ShadowOverlayHelper to include all options for ListRowPresenter:
hasOverlay, hasShadow, hasRoundedCorner, make decision whether to
create a wrapper.
Ultimately the extra layer ShadowOverlayContainer could be removed
and we can use setForeground() on any view for API>=23, but
animating foreground causes uncessary rebuildOutline() right now.
So we force to always use a wrapper for overlay.
b/22794753
Change-Id: I4848f7fc6b832706445da8e6e1b807d0f1830968
15 files changed
