flash player crashes when trying to enter fullscreen mode android 4.0

问题

So I've created an android app that plays video from blip.tv and various other flash-enabled websites. I use a Webview to display the video. Here is my code:

try{
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        getWindow().addFlags(LayoutParams.FLAG_KEEP_SCREEN_ON);
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);


        view = new WebView(this);
        view.getSettings().setPluginsEnabled(true);
        view.getSettings().setPluginState(WebSettings.PluginState.ON);

        view.getSettings().setJavaScriptEnabled(true);
        view.getSettings().setLoadWithOverviewMode(true);
        view.getSettings().setUseWideViewPort(true);
        view.setScrollBarStyle(WebView.SCROLLBARS_OUTSIDE_OVERLAY);
        view.setScrollbarFadingEnabled(true);


        // get the html code
        String html = getIntent().getStringExtra("VIDEO_CONTENT");

        view.loadData(html, "text/html", null);
        setContentView(view);
    }
    catch(Exception e){

    }

The problem is with android 4 (Ice Cream Sandwich). When I try to put the app into full screen mode, the app crashes. The app does NOT crash on android 2.3 or 3.0 however. Any ideas to fix this?

回答1:

This happens in ICS because the show() method in android.webkit.PluginFullScreenHolder gets called when trying to go to fullscreen mode. This method does the following:

WebChromeClient client = mWebView.getWebChromeClient();
client.onShowCustomView(mLayout, mOrientation, mCallback);

If you do not set the WebChromeClient on your WebView, you will get an NPE.

This fixed our crash, however the WebView disappears and the fullscreen video is not shown.

See: Android ICS 4.0 Placing Flash WebView into full screen calls hideAll Method?

*** Update:

Ultimately, in order to get my WebView to play flash videos in full screen mode I had to implement the onShowCustomView() method in my WebChromeClient in a fashion similar to what was done in the source code for the Android browser. The implementation of that method that I used for inspiration was in the BaseUI class:

https://github.com/android/platform_packages_apps_browser/blob/master/src/com/android/browser/BaseUi.java

I don't fully understand exactly what is happening here. I also wish I understood why the developers on ICS decided to require this method to be implemented. I wish I knew the value, or what problem this solved. In past versions, this fullscreen mode "just worked" now it requires a lot of digging.

回答2:

I was facing the same problem. I asked and got the following answer which works for me.
Hope this will help some people:
Create the FullscreenableChromeClient and add this line:

WebView.setWebChromeClient( new FullscreenableChromeClient(this));

    public class FullscreenableChromeClient extends WebChromeClient {
        protected Activity mActivity = null;

        private View mCustomView;
        private WebChromeClient.CustomViewCallback mCustomViewCallback;
        private int mOriginalOrientation;

        private FrameLayout mContentView;
        private FrameLayout mFullscreenContainer;

        private static final FrameLayout.LayoutParams COVER_SCREEN_PARAMS = new FrameLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT);

        public FullscreenableChromeClient(Activity activity) {
            this.mActivity = activity;
        }

        @Override
        public void onShowCustomView(View view, int requestedOrientation, WebChromeClient.CustomViewCallback callback) {
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.ICE_CREAM_SANDWICH) {
                if (mCustomView != null) {
                    callback.onCustomViewHidden();
                    return;
                }

                mOriginalOrientation = mActivity.getRequestedOrientation();
                FrameLayout decor = (FrameLayout) mActivity.getWindow().getDecorView();
                mFullscreenContainer = new FullscreenHolder(mActivity);
                mFullscreenContainer.addView(view, COVER_SCREEN_PARAMS);
                decor.addView(mFullscreenContainer, COVER_SCREEN_PARAMS);
                mCustomView = view;
                setFullscreen(true);
                mCustomViewCallback = callback;
                mActivity.setRequestedOrientation(requestedOrientation);
            }

            super.onShowCustomView(view, requestedOrientation, callback);
        }

        @Override
        public void onHideCustomView() {
            if (mCustomView == null) {
                return;
            }

            setFullscreen(false);
            FrameLayout decor = (FrameLayout) mActivity.getWindow().getDecorView();
            decor.removeView(mFullscreenContainer);
            mFullscreenContainer = null;
            mCustomView = null;
            mCustomViewCallback.onCustomViewHidden();
            mActivity.setRequestedOrientation(mOriginalOrientation);
        }

        private void setFullscreen(boolean enabled) {
            Window win = mActivity.getWindow();
            WindowManager.LayoutParams winParams = win.getAttributes();
            final int bits = WindowManager.LayoutParams.FLAG_FULLSCREEN;
            if (enabled) {
                winParams.flags |= bits;
            } else {
                winParams.flags &= ~bits;
                if (mCustomView != null) {
                    mCustomView.setSystemUiVisibility(View.SYSTEM_UI_FLAG_VISIBLE);
                } else {
                    mContentView.setSystemUiVisibility(View.SYSTEM_UI_FLAG_VISIBLE);
                }
            }
            win.setAttributes(winParams);
        }

        private static class FullscreenHolder extends FrameLayout {
            public FullscreenHolder(Context ctx) {
                super(ctx);
                setBackgroundColor(ctx.getResources().getColor(android.R.color.black));
            }

            @Override
            public boolean onTouchEvent(MotionEvent evt) {
            return true;
        }
    }
}

回答3:

Okay, so I think this is an android 4.0.2 / flash player problem, because other apps like browser and dolphin mini crash when flash is put into full screen mode.

来源：https://stackoverflow.com/questions/8660866/flash-player-crashes-when-trying-to-enter-fullscreen-mode-android-4-0