Q: localStorage

Localstorage uses simple key-value pairs.

To restore a value with javascript, use getItem with the name of your key:

localStorage.getItem(key);

To set a value with javascript, use setItem with the name of your key, and the value you want stored:

localStorage.setItem(key,val)

To use this with iAd Producer, you might want to set values on a text field using "Did Value Change" and executing a javascript that uses localStorage.setItem. To restore your values, you could load the values into a page's fields on the "View Will Appear" event.

Currently the key-values are not deleted whent the book is deleted from the shelf. To clear the values, you can use javascript.

For a specific key: localStorage.removeItem(key);

To clear all the keys: localStorage.clear();

The key is a string. You can use a literal string, or can use a string stored in a variable.

In iAd Producer, you can open the page with your text fields. Click the background for the page, then open the Inspector panel. At the bottom of the Inspector panel there is an "INTERACTION" section. Click on the "+" icon to create a new "View will Appear" event. Then select "Execute Javascript" for that event. Then click the ">" button to open the javascript code editor. If the outlet to your text field is named "textField" you could use javascript like this:

this.onViewControllerViewWillAppear = function (event) {

    var theValue = this.outlets.textField;

    if (localStorage.getItem("theKey") === null) {

        theValue.value = "Please enter some data";

    } else {

        theValue.value = localStorage.getItem("theKey");

    }

};

The above will restore the value in localstorage into the text field (or set it to "Please enter some data" if no value has been stored).

To set the value, click on your text field on the page.  At the bottom of the Inspector panel there is an "INTERACTION" section. Click on the "+" icon to create a new "Did Change Value" event. Then select "Execute Javascript" for that event. Then click the ">" button to open the javascript code editor. This javascript will store the value in localstorage using a key named "theKey":

this.onControlValueChange = function (event) {

    var theValue = this.viewController.outlets.textField;

    localStorage.setItem("theKey", theValue.value);

};

The above will store any changes in localstorage using a key named "theKey".

A great (and free) starting point for learning JavaScript is "Eloquent JavaScript":

http://eloquentjavascript.net/

What I provided was a simplified example to illustrate the basics. You will need to store/retrieve every key value pair separately from localstorage. One way to do that would be to duplicate what I provided, but it would be more efficient to write a reusable function (beyond the scope of this discussion thread).

The basic code to clear a value for a key in localstorage is:

localStorage.removeItem(key);

Where "key" is a variable containing the string for your key. You could replace this with a literal string as I did in the previous example.

Coming up with a namespace scheme is a good idea too.

Hi pazzle,

I'm curious to know if/how you were able to solve your problem of storing data entered in multiple text fields.

I'm facing the same problem and am currently stuck...

Are you still stuck?  If so, where are you stuck?