iframe videos won't go fullscreen mode in Android web view

You will need to create a custom WebChromeClient that handles both versions of onShowCustomView (a new version of this callback was introduced in API level 14) as well as onHideCustomView. Essentially what will happen is that when you attempt to play videos fullscreen, you will be given a view that is some variation of VideoView. You need to attach this to a fullscreen FrameLayout and stick it at the root of your layout hierarchy to overlay the entire screen. Once they're done you need to remove it again.

Here is a version I am using to play videos

private class DerpChromeClient extends WebChromeClient implements MediaPlayer.OnCompletionListener, MediaPlayer.OnErrorListener {    //@Override    public void onShowCustomView(View view, int requestedOrientation, CustomViewCallback callback) {        log.warn("onShowCustomView");        showCustomView(view, callback);    }    private View mVideoProgressView;    @Override    public void onHideCustomView() {        super.onHideCustomView();        activity.removeFullscreenView();        webView.setVisibility(View.VISIBLE);        try {            mCustomViewCallback.onCustomViewHidden();        } catch (NullPointerException npe) {            // occasionally Android likes to freak out and throw an unhandled NPE if it can't play the video            // therefore we are not going to do anything but eat this exception so it fails gracefully        }        mCustomView = null;        mVideoView = null;    }    @Override    public void onShowCustomView(View view, CustomViewCallback callback) {        super.onShowCustomView(view, callback);        log.warn("onShowCustomView");        showCustomView(view, callback);    }    private void showCustomView(View view, CustomViewCallback callback) {        if (mCustomView != null) {            callback.onCustomViewHidden();            return;        }        mCustomView = view;        mCustomViewCallback = callback;        webView.setVisibility(View.GONE);        if (view instanceof FrameLayout) {            if (((FrameLayout)view).getFocusedChild() instanceof VideoView) {                mVideoView = (VideoView)((FrameLayout)view).getFocusedChild();            }        }        view.setLayoutParams(new FrameLayout.LayoutParams(FrameLayout.LayoutParams.MATCH_PARENT, FrameLayout.LayoutParams.MATCH_PARENT));        view.setBackgroundColor(Color.BLACK);        activity.displayFullscreenView(view);    }    @Override    public boolean onConsoleMessage(ConsoleMessage cm) {        log.warn("Console Message: " + cm.message() + " on line " + cm.lineNumber() + " of " + cm.sourceId());        return super.onConsoleMessage(cm);    }    @Override    public void onProgressChanged(WebView view, int newProgress) {        super.onProgressChanged(view, newProgress);        if (newProgress < 100) {            if (loadingProgress.getVisibility() == ProgressBar.GONE) {                loadingProgress.setVisibility(ProgressBar.VISIBLE);            }            loadingProgress.setProgress(newProgress);        } else if (newProgress >= 100) {            loadingProgress.setVisibility(ProgressBar.GONE);        }    }    @Override    public View getVideoLoadingProgressView() {        if (mVideoProgressView == null) {            LayoutInflater inflater = LayoutInflater.from(KnowledgeBaseFragment.this.getActivity().getApplicationContext());            mVideoProgressView = inflater.inflate(R.layout.video_loading_progress, null);        }        return mVideoProgressView;     }    @Override    public boolean onError(MediaPlayer mp, int what, int extra) {        // TODO Auto-generated method stub        return false;    }    @Override    public void onCompletion(MediaPlayer mp) {        this.onHideCustomView();    }}

Note that I am doing this within a fragment, so to make it truly fullscreen I had to tightly couple it with the activity so it could attach the FrameLayout at the root of the entire view hierarchy, not just the fragment's.

Here are those functions:

@Overridepublic void displayFullscreenView(View customView) {    parentLayout.addView(customView);    this.customView = customView;}@Overridepublic void removeFullscreenView() {    if (customView != null) {        customView.setVisibility(View.GONE);        parentLayout.removeView(customView);    }    customView = null;}

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