FormItemValueFormatter.formatValue called multiple times

[vostapenko]

In v8.3p_2012-11-27/PowerEdition Deployment (built 2012-11-27)

TextItem's FormItemValueFormatter.formatValue() was called just once for the field

ds.xml

<field name="roles">

hibernate bean

@ManyToMany(targetEntity = Role.class, fetch = FetchType.LAZY)
    @JoinTable(name = "userrole", joinColumns = @JoinColumn(name = "UserID"),
            inverseJoinColumns = @JoinColumn(name = "URID"))
    public List<Role> getRoles()
    {
        return roles;
    }

    public void setRoles(List<Role> roles)
    {
        this.roles = roles;
    }

I was formatting incoming array accordingly.

Now in v8.3p_2012-12-04/PowerEdition Deployment (built 2012-12-04)

formatValue is called multiple times for each member of an array.

Before

JSOHelper.convertToJava(value) = {java.util.ArrayList@9297} size = 14
[0] = {java.util.LinkedHashMap@9299} size = 4
[1] = {java.util.LinkedHashMap@9300} size = 4
[2] = {java.util.LinkedHashMap@9301} size = 4
...

After

JSOHelper.convertToJava(value) = {java.util.LinkedHashMap@9234} size = 4
[0] = {java.util.LinkedHashMap$Entry@9237}"id" -> "3"
[1] = {java.util.LinkedHashMap$Entry@9240}"desc" -> "Право на просмотр протокола операций"
[2] = {java.util.LinkedHashMap$Entry@9243}"name" -> "R_OPERATIONS"
[3] = {java.util.LinkedHashMap$Entry@9246}"group" ->  size = 3

Is this a premanent change or a bug?

[Isomorphic]

Permanent change - actually a bugfix - with an array as the underlying value, there would be no way to correctly use a formatter/parser pair to round-trip the value unless calls are made for individual items.

[vostapenko]

Is there a simple way to overcome this?

I need to see "10 records chosen" inside a TextItem, before the fix it was as simple as JSOHelper.convertToArray((JavaScriptObject) value).length inside the formatter.

Now the field shows ", , , , , , , , , , , , ," even if i return null from it.
I can get the count of records with record.getAttributeAsRecordArray(item.getName()).length, but then i have "10 records,10 records,10 records,10 records,10 records,10 records".

Probably i can format just first item comparing value with record.getAttributeAsRecordArray(item.getName())[0]. But it requires smartgwt not to concat null values to ", , , , ,".

Anyway, the idea of formatting every chosen record is not good for me when a couple of thousand records is selected.

[vostapenko]

I've implemented this behavior using CanvasItem and

addShowValueHandler(new ShowValueHandler()
        {
            @Override
            public void onShowValue(ShowValueEvent event)
            {
                Object value = event.getDataValue();

                StringBuilder result = new StringBuilder("chosen ");
                int count = 0;
                if (value != null && value instanceof JavaScriptObject)
                {
                    Object[] valueMembers = JSOHelper.convertToArray((JavaScriptObject) value);
                    count = valueMembers.length;
                }

                result.append(count);
                textItem.setValue(result.toString());
            }
        });

Don't know, whether it's the easiest approach, but it works.