SuggestField doesn't show empty SuggestModel

[radekcz]

When we use SuggestField with overriden method:

private void serverFilterProcess(ServerFilterTriggerEvent serverFilterTriggerEvent) {
...
suggestField.setSuggestModel(prepareModel(inputData));
...
}

with set model over "setSuggestModel()" everything works fine. But if input text is not correct for suggestions and we want show empty suggestions (new SuggestModel(new SuggestItem[0])), last suggestions are still displayed (empty is expected?). This is not right behavior, is it?

[bentolor]

Doesn't sound right to me either.

Can you enable the over-the-wire logging of Echo (-D echo.syncdump=true -D echo.debug=true) or use the Firefox developer tools to see what actually is sent to the client.

I suspect echo swallowing the empty array completely as side effect of the synchronization optimization.

[radekcz]

Benjamin, thank you for your quick answer, there are communications between client and server:

Example 1 - Ok suggestions:

======== Request: 28 ========
<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<cmsg xmlns="http://www.nextapp.com/products/echo/svrmsg/clientmessage.3.0" i="28">
    <dir xmlns="" proc="CFocus">
        <focus i="C.3570"/>
    </dir>
    <dir xmlns="" proc="CSync">
        <e i="C.3570" t="async_triggerServerFilter">george </e>
        <p i="C.3570" n="selectionStart">7</p>
        <p i="C.3570" n="selectionEnd">7</p>
        <p i="C.3570" n="text">george </p>
    </dir>
</cmsg>

======== Response: 29 ========
<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<smsg xmlns="http://www.nextapp.com/products/echo/svrmsg/servermessage.3.0" i="29" u="">
    <libs/>
    <group i="init"/>
    <group i="update">
        <dir proc="CSyncUp">
            <up i="C.3570">
                <p n="suggestModel">{"suggestModel": {
  "suggestItems": [
    {
      "label": "Klasika BR: George London",
      "identifier": 595649221
    },
    {
      "label": "George of the jungle",
      "identifier": 208718958
    },
    {
      "label": "George Clinton Live na Jazz in Vienne",
      "identifier": 915101145
    },
    {
      "label": "George Michael v Pařížském paláci Garnier",
      "identifier": 2103031790
    },
    {
      "label": "George Harrison: Living in the Material World",
      "identifier": 1508631626
    }
  ]
}}</p>
           </up>
        </dir>
        <dir proc="CFocus">
            <focus i="C.3570"/>
        </dir>
    </group>
</smsg>

Example 2 - No (empty) suggestions:

======== Request: 29 ========
<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<cmsg xmlns="http://www.nextapp.com/products/echo/svrmsg/clientmessage.3.0" i="29">
    <dir xmlns="" proc="CFocus">
        <focus i="C.3570"/>
    </dir>
    <dir xmlns="" proc="CSync">
        <e i="C.3570" t="async_triggerServerFilter">george no</e>
        <p i="C.3570" n="selectionStart">9</p>
        <p i="C.3570" n="selectionEnd">9</p>
        <p i="C.3570" n="text">george no</p>
    </dir>
</cmsg>

======== Response: 30 ========
<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<smsg xmlns="http://www.nextapp.com/products/echo/svrmsg/servermessage.3.0" i="30" u="">
    <libs/>
    <group i="init"/>
    <group i="update">
        <dir proc="CSyncUp">
            <up i="C.3570">
                <p n="suggestModel">{"suggestModel": {
  "suggestItems": [
  ]
}}</p>
            </up>
        </dir>
        <dir proc="CFocus">
            <focus i="C.3570"/>
        </dir>
    </group>
</smsg>

[bentolor]

Hmmm... on trying to reproduce this effect in the Echolot sample application I already stumble over the behavior shown there: Typing only marks parts of the list but does not reduce the list of suggestions to match the search term.

That said: The component seems to be just a wrapper around a slightly modified JQuery Autocompletion Widget.

I was trying to quickly debug the source, but the way echo loads component scripts seems to hide them very successfully from the developer tools of Firefox & Chrome.

I'm already bit puzzled here: Do you get a filtered suggestion list at all?

[bentolor]

echo3/echo3@0c86592 and/or echo3/echo3@efe56d9 improves the debuggability of these scripts.

[radekcz]

Thanks for improvements debuggability! To question about filtered suggestion list: yes, we get a filtered suggestion list by overriden "serverFilter()":

@Override
public void serverFilter(ServerFilterTriggerEvent serverFilterTriggerEvent)
        // input data
        String inputData    = serverFilterTriggerEvent.getInputData();
        // do filter
        if (inputData != null){
            // get suggestField
            MySuggestField mySuggestField   = (MySuggestField)serverFilterTriggerEvent.getSource();
            // create and set new model                 
            mySuggestFieldI.setSuggestModel(prepareModel(inputData));
        }
    }

    /**
     * prepare model pro specific input
     * @param input
     * @return
     */
    private SuggestModel prepareModel(String input){
        // init suggest items
        ArrayList<SuggestItem> viewItems    = new ArrayList<SuggestItem>();
        // test of min lenght
        if ((input != null) && (input.length() >= MIN_LENGHT_DEFAULT)){
            // prepare suggestions for specific input by suggestManager
            arrayObjects    = suggestManager.getSuggestions(input, MAX_SUGGESTIONS_DEFAULT);
            // create suggest items
            for(T t : arrayObjects){
                // new Item
                SuggestItem suggestItem = new SuggestItem(t.getLabel());
                // add object to item
                suggestItem.setUserObject(t);
                // add Item to array
                viewItems.add(suggestItem);
            }
        }
        // convert to array
        SuggestItem[] arraySuggestItems = viewItems.toArray(new SuggestItem[viewItems.size()]);
        // create model
        SuggestModel suggestModel       = new SuggestModel(arraySuggestItems);
        // return model
        return suggestModel;
    }

It works fine except in the case of SuggestModel is empty. Then last suggestions are still displayed - in my opinion this is a bug. Suggestions should be empty.