Q: LocalStorage object available in iBooks?

Yes, the local storage object seems to be available, and saves its value between opening and closing books.

For example, in a html widget, set

localStorage.name=new Date();

and later on read

localStorage.name

which will return the date  previously stored, even if you've exited the book in-between.

Great news. An interesting use of this is that you can share data between different html bundle throughout your book.

@Rhys

Can you provide any examples of how you were able to accomplish this?  In my own tests, the variable seems to get wiped after I leave the widget, scroll a few pages, and then come back..

Any ideas?

@multimedial

On the surface, I would agree, functionality and capabilities seems to operate just like webkit, with one very big difference. It appears as if each time you enter a widget, the system instantiates a new safari instance in memory.  Once you have moved a few pages away from the widget, it wipes that safari instance.  In this way, any variables, cookies, even session identifiers disappear.  At least, that has been my experience thus far. I would love yo hear of anyones success in this arena.

Using localStorage, I successfully saved user entered notes in a widget. When moving to some other pages, using other html widgets, and coming back, texts are still there. I even tried closing the book, quitting iBooks, force iBook to quit (using app switcher), texts were still there when I reopened the book.

@Frato

Can you provide any sample code? I have done such and it has worked effectively in any outside browser and it works, but I cant get it to work in the widget correctly...

Here is some sample code that stores and gets some text from localStorage:

<textarea id="sometext" rows="15" cols="100"></textarea>

</br>

<input type="submit" value="Save to localStorage" onclick="save_localstorage()" />

<script type="text/javascript">

    var sometext = localStorage.sometext;

    if (sometext) {

        document.getElementById("sometext").value = sometext;

    }

    function save_localstorage() {

        localStorage.sometext = document.getElementById("sometext").value;

    }

</script>

I've also placed it in an example widget for you to download at:

http://www.classwidgets.com/static/LocalStorageTest.wdgt.zip

@Rhys

Thanks man, that helped me figure out my issue.

Hmm. It looks like this is working in iBooks if I create a widget in Dashcode and put it in an iBook. However, it doesn't seem to work in Dashcode? Will make debugging more difficult. Is this what others are seeing? Is there someway to get Dashcode to use localStorage? Is there other software for iBooks widget development that would do this better? Thanks.

Rhys_Jones wrote:

 

Here is some sample code that stores and gets some text from localStorage:

 

<textarea id="sometext" rows="15" cols="100"></textarea>

</br>

<input type="submit" value="Save to localStorage" onclick="save_localstorage()" />

 

<script type="text/javascript">

    var sometext = localStorage.sometext;

    if (sometext) {

        document.getElementById("sometext").value = sometext;

    }

    function save_localstorage() {

        localStorage.sometext = document.getElementById("sometext").value;

    }

</script>

 

I've also placed it in an example widget for you to download at:

 

http://www.classwidgets.com/static/LocalStorageTest.wdgt.zip

@Rhys: Can you confirm if this still works?  I'm also having trouble with localStorage - I inserted the widget you supplied and it fails to work. If I close the widget and reopen it, the storage is wiped. I'm using iBooks Author 1.1 (190) and iBooks 2.1 (876) on an iPad 2.

Thanks.

LocalStorage was broken after I upgraded (both iOS and iBooks) to latest version. I had to delete iBooks on the ipad and install it again to make localStorage work again.

Francis.

Just had the same experience with the latest 2.1.1 update. After updating on my iPad, localStorage was completely broken. None of the values stored by the widgets could be retrieved again. Killing and restarting iBooks made no difference.

After deleting iBooks on my iPad and reinstalling it, localStorage works fine again.

Michi.

multimedial wrote:

 

What about the database object?
According to Apple's documentation, it seems as if the Web Database object should also be available - anyone got news on this?

Well, I don't know if it qualifies as "news" given the age of this thread, but yes, I've tried and the JavaScript database seems to work. This opens up the possbility for storing some rather rich data with complex relationships. Cool.

-Steve