EditorInfo始终返回空的mime-type数组

Question

EditorInfoCompat.getContentMimeTypes（editorInfo）;总是返回空的suppimeted mime类型数组。我在google messenger应用程序和谷歌提供的demo commitcontent支持应用程序中进行了调试。这个波纹管代码片段总是返回false。请帮忙！

final String[] supportedMimeTypes = EditorInfoCompat.getContentMimeTypes(editorInfo);
    for (String supportedMimeType : supportedMimeTypes) {
        if (ClipDescription.compareMimeTypes(mimeType, supportedMimeType)) {
            return true;
        }
    }
 return false;