Android Webview and Flash

Android Webview and Flash

I need to get http://www.plupload.com/ working in my webview I did try
mWebView.getSettings().setJavaScriptEnabled(true);
mWebView.getSettings().setPluginState(PluginState.ON);
and nothing happens.. I did install :
https://play.google.com/store/apps/details?id=com.rg2333g53t244frf.flash.player
and its working.. but the filechooser is not nice (like default browser)
and i cant ask clients to install this package and check unknown sources..
Someone here with a valid solution ? (Could i half silently install the
above apk from my assets folder without root ?) Why is flash working in
normal android Browser and in my webview only if i install the above
Plugin ?