For example, read version from JSON file. In build.gradle, in my case it is in: /app/build.gradle write something like:

def computeVersionName() {
    def f1 = new File("app/src/main/assets/version.json");
    def json = new JsonSlurper().parseText(f1.text)

    assert json instanceof Map
    return json.version

android {
    compileSdkVersion 22
    buildToolsVersion "22.0.1"
    defaultConfig {
        applicationId 'myId'
        minSdkVersion 16
        targetSdkVersion 22
        versionCode 2
        versionName computeVersionName()
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), ''
    productFlavors {


versionName computeVersionName()

It seems that androids WebView doesn't like video tag.

Here is Android code which worked for me:

        mWebView.setWebViewClient(new WebViewClient() {
            // autoplay when finished loading via javascript injection
            public void onPageFinished(WebView view, String url) {
                mWebView.loadUrl("javascript:(function() { document.getElementsByTagName('video')[0].play(); })()");

        mWebView.setWebChromeClient(new WebChromeClient());

Where WebChromeClient we need to handle javascript methods, and it seems that autoplay in WebView doesn't work.

Also, mWebView is: private WebView mWebView; (I took example of WebView based application)

HTML code looks like:

<video autoplay loop>
	<source src="" type="video/mp4">

To debug your web application in Android in Chrome write:


and click inspect:

Before that in Android code write:


Here you can see an example of creating WebView for Android. Problem which I had was to load a local file. Simple answer is like this:


Where android_asset is actually assets folder in Android project. To add assets to the Android project, choose view to Android, right click on the app -> New -> Folder -> Assets folder:

Now the whole code can look something like this: 

    protected void onCreate(Bundle savedInstanceState) {
        mWebView = (WebView) findViewById(;
        WebSettings webSettings = mWebView.getSettings();