Does webview create a separate surface like videoview does?

Issue

I have a confusion and look forward to some comments on this. I was assuming that WebView creates a separate surface to draw and does not use the default surface of the activity to draw. But, in surfaceflinger dump, I dont see a new surface getting created when using webview.

When I do the similar experimnet of using videoview, I see a separate surface getting created.

Onwebview also, I wanted to play a video, so was assuming a separate surface would be created and thereby the surface resolution would be as per video resolution. But if it uses application's surface, then the max resolution of the video has to be of the UI resolution.

In chromium code, I see the code for separate surface but then in practical I could not see one getting created.

Can someone help me to clarify this.

Thank You.

Solution

If you look at VideoView inheritance graph you'll notice that it inherits from SurfaceView, while WebView does not, so WebView can only achieve that by creating an external SurfaceView.

While if you search for usages of ExternalVideoSurface in WebView part of Chromium code, you will notice that it is only enabled if "video hole" is enabled, which is intended to be used only for decoding encrypted videos, where WebView needs to do "hole punching". There is a System API-level setting in WebView that enables this behaviour, but it has its own limitations, and thus not recommended to be used in general.

Answered By - Mikhail Naganov