Invoke unity function from Javascript or listen/trigger from redirect http response

[paatz04]

Hey there! Awesome work.

I was wondering if there is a way to listen to javascript function and invoke a unity function.
I couldn't find a documentation. Any hints ?

I would like to build a user login form and a short quizz and use that in my webview. I need to somehow listen to the submit event and close the webform. Or can i register to redirects ? For example close the webview when a certain response is returned.

Do I have to work with the init function I suppose ? I assume I can use cb - > call from JS. Do you have a JS sample that would trigger cb?

Thanks!

[KojiNakamaru]

The sample app shows how to interract between Unity and HTML. If you want to call the Unity-side, you can utilize Unity.call(), for example:

unity-webview/sample/Assets/StreamingAssets/sample.html

Line 13 in 95fc7af

<p><a href="javascript:void(0)" onclick="Unity.call('anchor');">[Send Message!]</a></p>

If you want to call the JavaScript-side, you can utilize EvaluateJS(), for example:

unity-webview/sample/Assets/StreamingAssets/sample.html

Line 13 in 95fc7af

<p><a href="javascript:void(0)" onclick="Unity.call('anchor');">[Send Message!]</a></p>

[paatz04]

Hey! Thanks for the quick and prompt reply!
So : <p><a href="javascript:void(0)" onclick="Unity.call('anchor');">[Send Message!]</a></p>
Calls the cb action added to the webViewObject.init() with the msg="anchor" ?

[KojiNakamaru]

Yes, it behaves as you noted. So you can communicate between Unity and HTML (JavaScript) in both directions.

[paatz04]

Thanks a lot! Easy and simple. I'm about to use it in production. Are you aware of any limitations on iOS / android ? Does it support Android SDK >=15 and iOS >=8? Cheers
It works fine on my devices 👍

[KojiNakamaru]

Yes, it should run well on android with API version 15 or later and iOS 8 or later.

[paatz04]

what is a production ready pre-processor flag for android and iOS. The sample app uses:

#if !UNITY_ANDROID // NOTE: depending on the situation, you might prefer // the 'iframe' approach. // cf. https://github.com/gree/unity-webview/issues/189 #if true webViewObject.EvaluateJS(@" window.Unity = { call: function(msg) { window.location = 'unity:' + msg; } } "); #else webViewObject.EvaluateJS(@" window.Unity = { call: function(msg) { var iframe = document.createElement('IFRAME'); iframe.setAttribute('src', 'unity:' + msg); document.documentElement.appendChild(iframe); iframe.parentNode.removeChild(iframe); iframe = null; } } "); #endif #endif

But that doesn't work on android at all.
Does going with

webViewObject.EvaluateJS(@" window.Unity = { call: function(msg) { window.location = 'unity:' + msg; } } ");

Work in any case for android >15 and ios>8. Or what do you suggest?

When calling LoadURL(), is there a way to clear the webview (show white while loading) instead of showing the previous website until it finishes loading ?

I saw you were referencing this issue: #189
Thanks!

[KojiNakamaru]

The sample app doesn't define Unity.call():

unity-webview/sample/Assets/Scripts/SampleWebView.cs

Lines 49 to 74 in e5f1576

	#if !UNITY_ANDROID
	// NOTE: depending on the situation, you might prefer
	// the 'iframe' approach.
	// cf. https://github.com/gree/unity-webview/issues/189
	#if true
	webViewObject.EvaluateJS(@"
	window.Unity = {
	call: function(msg) {
	window.location = 'unity:' + msg;
	}
	}
	");
	#else
	webViewObject.EvaluateJS(@"
	window.Unity = {
	call: function(msg) {
	var iframe = document.createElement('IFRAME');
	iframe.setAttribute('src', 'unity:' + msg);
	document.documentElement.appendChild(iframe);
	iframe.parentNode.removeChild(iframe);
	iframe = null;
	}
	}
	");
	#endif
	#endif

because Unity.call() is defined in WebViewPlugin.jar:

unity-webview/plugins/Android/src/net/gree/unitywebview/CWebViewPlugin.java

Lines 60 to 63 in e5f1576

	@JavascriptInterface
	public void call(final String message) {
	call("CallFromJS", message);
	}

unity-webview/plugins/Android/src/net/gree/unitywebview/CWebViewPlugin.java

Line 185 in e5f1576

webView.addJavascriptInterface(mWebViewPlugin , "Unity");

When calling LoadURL(), is there a way to clear the webview (show white while loading) instead of showing the previous website until it finishes loading ?

You could utilize EvaluateJS() and/or LoadHTML() to show some loading animation while redirecting to the next page.

[paatz04]

Thank you!!! That means it should work without the injection for android, so I can use the compiler flag, and therefore only inject it through EvaluateJs for iOS or does it do a similar thing for iOS?
I noticed injecting it for android as well works anyway though

At the moment it works fine with your sample.html but the same call on my page isn't fired. Any tipps on how to debug ?

[KojiNakamaru]

Thank you!!! That means it should work without the injection for android, so I can use the compiler flag, and therefore only inject it through EvaluateJs for iOS or does it do a similar thing for iOS?

The injection is required only for iOS. If you only utilize WKWebView (by specifying enablWKWebView: true and limiting iOS versions to 8 or later), you can utilize more efficient/reliable window.webkit.messageHandlers.unityControl.postMessage() (introdueced by @dragonx in #161) instead of Unity.call() and don't need the injection.

I noticed injecting it for android as well works anyway though

Yes, it also works because unity: prefixed URLs can also work for Android. However, natively defined Unity.call() should be more efficient.