Implement custom metadata support

Callback functions are invoked just before the tracking call is made, so your application can attach the metadata that is specific to an ad or chapter.

Invoke callback functions for content, ads, and chapters.

// Video Metadata Block
vaMetadata.setVideoMetadataBlock(new VideoAnalyticsMetadata.VideoMetadataBlock() {
    @Override
    public HashMap<String, String> call() {
        HashMap<String, String> result = new HashMap<String, String>();
        result.put("myvideoid", "1234");
        result.put("mysdkversion", Version.getVersion());

        return result;
    }
});

// Ad Metadata Block invoked on every ad start
vaMetadata.setAdMetadataBlock(new VideoAnalyticsMetadata.AdMetadataBlock() {
    @Override
    public HashMap<String, String> call(Ad ad) {
        HashMap<String, String> result = new HashMap<String, String>();
        result.put("myadid", "ad-1234");
        result.put("myad-sdkversion", Version.getVersion());

        return result;
    }
});

// Chapter Metadata Block invoked on every chapter start
vaMetadata.setChapterMetadataBlock(new VideoAnalyticsMetadata.ChapterMetadataBlock() {
    @Override
    public HashMap<String, String> call(VideoAnalyticsChapterData chapter) {
        HashMap<String, String> result = new HashMap<String, String>();
        result.put("mychapterid", "chapter-1234");
        result.put("mychapter-sdkversion", Version.getVersion());

        return result;
    }
});