Crosswalk 13: Set Cache Mode

Question

I've recently migrated from android webview to Crosswalk 13. The only issue i've run into is telling the XWalkView to load content from the app cache.

In my android webview implementation i had implmemented as this

//check connection on a loop
public void CheckConnectivityTask(){


    new AsyncTask<Void, Void, Void>() {         
        @Override
        protected Void doInBackground(Void... params) {

            //runs every 0.5s
            try {
                Thread.sleep(500);
            } catch (InterruptedException e) {

            }

            return null;
        }

        @Override
        protected void onPostExecute(Void result) {
            CheckConnectivity(true);
        }

    }.execute();
}


public void CheckConnectivity(boolean recursiveTask){
    cm = (ConnectivityManager) getSystemService(Activity.CONNECTIVITY_SERVICE);
    if(cm != null && cm.getActiveNetworkInfo() != null && cm.getActiveNetworkInfo().isConnected()){
        Log.v("ConnectivityGG", "IS CONNECTED");
        mainWebView.getSettings().setCacheMode(WebSettings.LOAD_DEFAULT);
    }
    else{
        mainWebView.getSettings().setCacheMode(WebSettings.LOAD_CACHE_ELSE_NETWORK);
    }
    if(recursiveTask){
        CheckConnectivityTask();
    }
}

As getSettings() has now been removed from XWalk 13, I've been trying to set this using XWalkSettings

inside OnCreate in MainActivity

xWalkSettings = new XWalkSettings(mainWebView.getContext(), null , false);
xWalkSettings.setAppCacheEnabled(true);

and then modifying my looped task

public void CheckConnectivity(boolean recursiveTask){
    cm = (ConnectivityManager) getSystemService(Activity.CONNECTIVITY_SERVICE);
    if(cm != null && cm.getActiveNetworkInfo() != null && cm.getActiveNetworkInfo().isConnected()){
        xWalkSettings.setCacheMode(WebSettings.LOAD_DEFAULT);
    }
    else{
        xWalkSettings.setCacheMode(WebSettings.LOAD_CACHE_ELSE_NETWORK);
    }
    if(recursiveTask){
        CheckConnectivityTask();
    }
}

However any attempt to load cached pages fails with "Internet connection has been lost" alert dialogue. Am I instantiating the XWalkSettings instance incorrectly, or is there another way of achieving this?

Answer 1

I found a way from this link. And changed it slightly. Basically need to use reflection to get access to a non public (afaik) method.

Method ___getBridge;
    try {
        ___getBridge = XWalkView.class.getDeclaredMethod("getBridge");
        ___getBridge.setAccessible(true);
         XWalkViewBridge xWalkViewBridge = null;
        xWalkViewBridge = (XWalkViewBridge)___getBridge.invoke(mainWebView);
        xWalkSettings = xWalkViewBridge.getSettings();
        xWalkSettings.setAppCacheEnabled(true);
    } catch (NoSuchMethodException e1) {
        // TODO Auto-generated catch block
        //e1.printStackTrace();
    } catch (IllegalArgumentException e) {
        // TODO Auto-generated catch block
        //e.printStackTrace();
    } catch (IllegalAccessException e) {
        // TODO Auto-generated catch block
        //e.printStackTrace();
    } catch (InvocationTargetException e) {
        // TODO Auto-generated catch block
        //e.printStackTrace();
    }

If there's a nicer, cleaner way of doing this I'd love to know :)

Answer 2

Crosswalk didn't expose setCacheMode API before, but it has been exposed recently, please see this JIRA, https://crosswalk-project.org/jira/browse/XWALK-6832

It should be available in Crosswalk 21, you can use it like below:

mXWalkView.getSettings().setCacheMode(XWalkSettings.LOAD_NO_CACHE);

So, enjoy it.. :)