iOS上的Cordova inAppBrowser中的executeScript执行不一致

Question

I'm having some trouble with some inAppBrowser behavior in my cordova app. Here's the code:

var codePass = fooCode;
var executeScriptFunc = function(event) { 
  ref.executeScript({
    code: codePass
  }, function (value) {});
  ref.removeEventListener('loadstop', executeScriptFunc);
};

var ref = cordova.InAppBrowser.open(fooObject.link, "_blank", "location=yes,enableViewportScale=yes");
ref.addEventListener('loadstop', executeScriptFunc)

The strange thing here is that the code works perfectly every time when emulated. It opens the browser and executes the script no problem. But when I try it on my actual iPhone device, it doesn't always work. The script executes maybe every other time. But it's never even that consistent.

Both the emulator and iPhone are using iOS 9.3.4. Any ideas?

Answer 1

If the site inside the inAppBrowser happens to be served via HTTPS, the callback for executeScript() will not work if the site employs a Content-Security-Policy HTTP response header that does not contain the gap: or gap-iab: schemes for the default-src directive. These are needed because execution of the callback function on iOS relies on an iframe that gets added to the page .

You can check whether this is the root cause for the problem by opening Safari's Web Inspector for the inAppBrowser—it has a separate Web Inspector instance, independent of the parent application that opened it—and look out for a corresponding error message in the console. Note that you should open the console before executeScript() is run, or otherwise you might not get the error message.

Answer 2

Make sure also that you don't have other event handlers firing at the same time during your polling.

I had multiple pollers all firing every second and that's when I ran into the issue.

After changing the polling time so they all fired at different times, the issue went away.