IMP: ZK support to IPhone features

answered 2012-10-05 10:55:43 +0800

gekkio
899 ● 1
http://gekkio.fi/blog

1. As I mentioned in the other thread, this is not possible without a native app.
2. This can be done with custom Javascript. See the W3C Geolocation API.
3. Not possible without a native app.
4. Normal file upload should work for this.

answered 2012-10-05 17:44:17 +0800

windeyu
288 ● 3

Long ago I experimented with our ZK web application being wrapped by PhoneGap to produce a native program on Android. It ran fine on an Android emulator. (PhoneGap also supports iPhone.) In a nutshell, the produced native mobile program is like a mini-browser loading your web page, and providing access to native features like camera, gps to your client-side javascript. I imagine you can write your own custom ZK component and its client-side widget. Inside your client-side widget, you can load PhoneGap javascript library to access the native camera, gps, contacts, etc, and pass on the info back to your server component. I haven't completed this whole path, but I think it should be fun to give it a try.

answered 2012-10-09 06:28:22 +0800

gekkio
899 ● 1
http://gekkio.fi/blog

Hmm, using Phonegap is a very interesting approach. My guess is that the PhoneGap app will basically redirect to a ZK app running elsewhere (= you don't package ZK stuff in the Phonegap native app). This article about Vaadin and PhoneGap might give you some ideas. Vaadin and ZK are very similar, so some basic principles of the integration apply to both frameworks.

answered 2012-10-10 04:46:17 +0800

windeyu
288 ● 3

updated 2012-10-10 04:47:50 +0800

I did this long ago, but I think it still works in the same way. Please see the the sample Hello World app in this tutorial:

http://docs.phonegap.com/en/2.1.0/guide_getting-started_android_index.md.html#Getting%20Started%20with%20Android

The PhoneGap code is very simple. It calls

    super.loadUrl("file:///android_asset/www.index.html");

I somehow managed to load the URL that pointed back to a zul page in my backend server. I don't remember the details, but I found a link below that may explain in concrete code. I didn't go further beyond ths point. At least it showed me that PhoneGap worked fine with the ZK client-side library. (It was ZK 5 and an earlier version of PhoneGap I tested.) You have to try out yourself from here. Good luck.

http://comments.gmane.org/gmane.comp.handhelds.phonegap/23680

answered 2012-10-18 09:03:49 +0800

vinayakshukre
36

windeyu, thanks for the information. I have few thoughts to add to this.

Phonegap basically provides the JS APIs to access native functionality like camera or addressbook. So developer has to write the javascript either in separate file or in HTML file to call those phonegap JS APIs. Phonegap also provides one jar file which probably has the native code to access native functionality which is called from phonegap JS APIs.

When mobile application is built from these JS and HTML files into a .APK file for android or something else for iPhone, it somehow identifies the JS calls for native functions and replaces/compiles them with native code.

In case of ZK, javascript is generated runtime and even if you write ZK page which generates the JS which calls the phonegap API , it does not go through the process of compiling/replacing call with native code. So those calls do not work.

So using phonegap and ZK to build mobile application which can access native feature seems impossible to me. But you can always call ZK URL (explained by windeyu above) and see ZK pages launched from within the application. So you can take the advantage of ZK widgets in mobile app but can not have native features.

Even ZK team can not fix this as it is beyond their control. ( In reality I would want to hear from them that this is possible. I would be happy in that case as that will solve my problem.)

Anybody from ZK team, please reply.

answered 2012-10-22 06:27:53 +0800

windeyu
288 ● 3

Hello vinayakshukre, thanks for sharing your thoughts on my idea. If what you said were correct, my idea would've been too naive. However, I have another idea to make it work.

The key to the new idea is the iframe and the cross-window messaging with postMessage(). Over the weekend in my spare time, I tried this out and seemed promising.
The pseudo-code is like this

<!--  This is the index.html to be compiled by PhoneGap to produce native mobile program -->
<html>
  <script>
    <!--
        Here you write javascript to send and receive messages to the DOM window in the iframe.
        Your listener here also invokes PhoneGap api to access phone's features such as gps, contacts, etc
     -->
  </script>
  <body>
	<iframe id="content" src="http://xxxx/your_ZK_application.zul"></iframe>
  </body>
</html>

http://javascript.info/tutorial/cross-window-messaging-with-postmessage
http://viget.com/extend/using-javascript-postmessage-to-talk-to-iframes
https://groups.google.com/forum/#!msg/phonegap/ZhOgsCbnDqw/CXgmz6kxf-cJ

I verified this cross-iframe messaging with a sample phoneGap app running on my Galaxy S3 and a iframe html page running from my ZK web application deployed on a tomcat. I was able to send messages back and forth across the iframe. However, I have trouble porting the javascript in my html page deployed in the ZK app to a custom ZK widget. I am not an expert with zk client-side programming. However, I do see this idea promising to get it work eventually.

Hope this information help.
Best regards.

answered 2012-10-22 11:48:39 +0800

vinayakshukre
36

Its really great to share this kind of idea.....you know why ? Somehow the same idea came to my mind....believe me and I am trying this. Will let you know my findings soon.

answered 2012-10-31 12:16:33 +0800

vinayakshukre
36

I could make it work with this iFrame idea but I am not sure is it a good idea to use in any real world commercial application.
It will be great to have some OOTB feature of ZK.

ZK developers...do you have any plan to support this ?