Hi, I've put together a small demo of a grid like html component which makes use of a JSON string in a hidden input field (tapestry component) to convey state between the client and server.
http://cruise.sadalbari.com:8080/tapestry-prototypes/GridDemo.html Basically each entry in the grid is an ActionEntry (a javascript class which has its java counterpart on the server side). ActionEntries contain 3 fields 1) A unique id (this is a client assigned unique id) 2) An action (either ADD, UPDATE, DELETE or NONE) 3) An embedded object - which in this case is a GridEntry object with a code and amount Editing of the html entries fires javascript events which update the object model (in the client). When the user clicks "Save", the object model - an array of action entries is converted to a JSON String and submitted (using a tapestry form) to the server. On the server side, I manually convert the JSON string to an object graph and then apply the necc. changes (ADDING, UPDATING, DELETING etc) One big drawback is that because the component is dynamic HTML, I can't apply validation (and translation) using the normal tapestry mechanisms. I've hacked around this by including a hidden div containing an @TextField component which contains the same attributes (translators, validators) that I wish to apply to each of the amount input fields. <div style="display:none"> <input jwcid="[EMAIL PROTECTED]" disabled="true" value="ognl:amount" id="amount" validators="validators:required" translator="translator:number" displayName="amount" /> </div> So then on the server side (and this is where it gets ugly) I use this component to do translation and validation, catching the validation errors and populating a validation delegate. TextField comp = (TextField)component; Object object = comp.getTranslatedFieldSupport().parse(comp, jsonValue == JSONObject.NULL ? null : jsonValue.toString()); comp.getValidatableFieldSupport().validate(comp, null, cycle, object); I'm a newbie to tapestry and JSON - but am willing to share this contribution to anyone that may find it useful. I'd also like to improve on the validation - so if anyone has any suggestions on how do this in a more elegant manner let me know. Thanks -- Justin Walsh http://www.ewage.co.za --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
