Information on GWT-Plus

GWT-Plus is an addon module to GWT-Ext.

Here are the high level features of the Store / GWT-RPC integration :

• Integrates the data returned by a GWT-RPC service call into a GWT-Ext Store
• Also supports loading a List of local beans into a GWT-Ext Store
• Transparent and seamless mapping of Store and Record API's with the underlying user JavaBean object
• Support for read and write of nested JavaBean properties (unlimited nesting)
• Store#getModifiedRecords() allows you to get a list of modified JavaBean objects which can then be sent to the server
• Fine grain control of which properties are exposed to the Record API as fields
• Integration of GWT-RPC exception with associated Store exceptions
• Propagation of sort / page / filter and user defined parameters to user's RPC call in a flexible way without enforcing a specific API on the RPC call
• Support for GWT 1.5 and Generics

With this functionality you'll be able to specify your GWT-RPC service API that returns a list of domain beans / DTO's and load it into a Store which can be used to display data in a Grid, ComboBox or a Form. If you're using an EditableGrid, any modifications to the data will be reflected in your underlying data beans. You can retrieve the modified beans by calling Store#getModifiedRecords() and then make a GWT-RPC call to persist the changes. Sorting / Paging and Filtering of Grid data is also greatly simplified as the table sort / page / filter parameters are made accessible to your service and you can have your backend return data based on these parameters / criteria.

The GWT-Plus package presently ships with a few samples :

• Demo of an EditableGrid which gets data using GWT-RPC and also demonstrates passing back the modified beans to the server. Additionally the table paging parameters (page size , page num) and sorting parameters from the Grid are made available to the RPC call and passed to the server.
• Same as above except that the data is laoded using a List of local data beans.
• An example of ComboBox - Form - Grid example where all three widgets are bound to the same underlying data which is retreived using a GWT-RPC call. The ComboBox data is pageable, and a selection dispalys to corresponding Record in the Form and Grid. Selecting a row in the Grid results in the selected Record being dispalyed in the Form. Editing the Record in the Form reflects in the Grid and conversely editing a cell in the Grid reflects in the Form.
• Same as above except that the data is loaded using a List of local data beans.

The examples will grow over time to include master - detail tables, related combos etc. and I will post updates.

Buy GWT-Plus

You can find information on purchasing GWT-Plus here.

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Below is some sample code illustrating the usage of GWT-Plus Store / RPC integration that should give you a good idea of how things work.

final MyServiceServiceAsync myservice = ...

BeanProxy proxy = new BeanProxy(new RemoteLoader() {
            public void load(AsyncCallback callback, FetchCriteria fetchCriteria) {
                   //your application service API call,
                   //for example
                   myservice.getPersons(callback);
            }});


//here Person class is your Bean class.
BeanAdapter beanAdapter = (BeanAdapter) GWT.create(Person.class);

//either get a generated RecordDef with all the bean properties
RecordDef recordDef = beanAdapter.getRecordDef();

//or simply create on yourself as usual explicilty listing the properties
RecordDef recordDef  = new RecordDef(new FieldDef[]{
                new StringFieldDef("name"),
                new StringFieldDef("birthday"),
                new StringFieldDef("state", " person.address.state")  //can also bind nested properties
               });

BeanReader reader = new BeanReader(beanAdapter, recordDef);

final Store store = new Store(proxy, reader);
store.addStoreListener (new StoreListenerAdapter() {
    public void onLoad(Store store, Record[] records) {
        super.onLoad(store, records);
        Record record = records[0];
        record.set( "name", "sanjiv");
        //this is your server java bean
        Person bean = (Person) record.getDataAsObject();
    }

    public void onLoadException(Throwable error) {
        //here you get any RPC related exception (eg any exception your service API may throw)
    }
});

store.load ();	
	

Modifications made to the Records will be aware of underlying beans. So edits to rows in a grid will result in updates to the underlying bean. To find modified beans, call Store#getModifiedRecords(), iterate over each record and extract your Bean via record.getDataAsObject(). Then pass to server to save or whatever, and then call store#commit() as usual.

Questions?

Please send mail to gwt.plus@gmail.com.

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