如何防止用户在 Android Crosswalk WebView 中截取屏幕截图？

Question

I'm trying to prevent from taking a screenshot in Crosswalk WebView. I have tried PrivacyScreenPlugin . This plugin works very good when I wasn't using Crosswalk plugin. However, if I added Crosswalk plugin, it only works at the app launch time.
For example, when I launch my app, I can not take a screenshot. However, if I show any other UI component (such as volume control, etc..), my app start allowing to take a screenshot.

I found this related question and one person mentioned that if I use Crosswalk, I need to modify PrivacyScreenPlugin/Crosswalk.

Here is what I tried:
In Crosswalk WebView plugin, XwalkWebViewEngine#init method.

cordova.getActivity().getWindow().setFlags(WindowManager.LayoutParams.FLAG_SECURE, WindowManager.LayoutParams.FLAG_SECURE);

However, above code wasn't fix my issue.
And, I couldn't find a place to modify in PrivacyScreenPlugin.

I'm using following Android versions and plugins:

• Android 5.0.2
• Crosswalk plugin 1.6.1
• PrivacyScreenPlugin 0.2.0

Any comment would be appreciated.

Answer 1

According to this ticket. There is a temporary workaround to avoid this issue.

In AndroidManifest.xml:
Replace

android:theme="@android:style/Theme.Black.NoTitleBar"

with

android:theme="@android:style/Theme.Holo.Light.NoActionBar"

Answer 2

This workaround worked for me. It basically digs to the SurfaceView that XWalkView creates and makes it secure:

if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN_MR1) {
    ((SurfaceView)((FrameLayout)((FrameLayout) mXWalkView.getChildAt(0)).getChildAt(0)).getChildAt(0)).setSecure(true);
}

Looks ugly but worked like a charm.